Inorganics

32 pages, 3558 KB

Open AccessReview

Thermoelectric Materials for Spintronics: From Physical Principles to Innovative Half Metallic Ferromagnets, Devices, and Future Perspectives

by Alessandro Difalco and Alberto Castellero

Inorganics 2025, 13(10), 332; https://doi.org/10.3390/inorganics13100332 - 2 Oct 2025

Abstract

Over the last century, improvements in computational power resulting from the exponential growth of microelectronics have been the driving force of outstanding global economic growth as well as of deep changes in society and ethical values. Manufacturing of silicon-based memory cells has, as [...] Read more.

Over the last century, improvements in computational power resulting from the exponential growth of microelectronics have been the driving force of outstanding global economic growth as well as of deep changes in society and ethical values. Manufacturing of silicon-based memory cells has, as a matter of fact, become an industry of strategic importance also from a geopolitical perspective. Despite such advancements, a lot of concern has recently aroused as physical limitations such as tunnel-effect phenomena, current leakage, and high power consumption are increasingly hindering further improvements in dynamic random-access memory. Spintronic technologies are promising alternatives to overcome such issues, being considered no longer merely an academic subject of interest, but increasingly becoming an industrial reality. In this review work, the history and the physical principles of spintronic devices are presented, focussing on new, groundbreaking materials. Concepts are exposed step by step and in an easy-to-understand manner, allowing even researchers who are not specialized in the fields of spintronics, microelectronics, and hardware engineering to understand the fundamentals and gain initial insight into the topic. Special attention is paid to half-metallic ferromagnets and Heusler alloys, which are considered among the most promising materials for the future of spintronics. Full article

(This article belongs to the Special Issue Advances in Thermoelectric Materials, 2nd Edition)

► Show Figures

Figure 1

16 pages, 3501 KB

Open AccessArticle

A Comprehensive Study of the Optical, Structural, and Morphological Properties of Chemically Deposited ZnO Thin Films

by Sayra Guadalupe Ruvalcaba-Manzo, Rafael Ramírez-Bon, Ramón Ochoa-Landín and Santos Jesús Castillo

Inorganics 2025, 13(10), 331; https://doi.org/10.3390/inorganics13100331 - 2 Oct 2025

Abstract

Zinc oxide (ZnO) is a wide bandgap semiconductor with optoelectronic and photocatalytic properties, which depend on its optical, structural, and morphological characteristics. In this study, we synthesized ZnO thin films by chemical bath deposition (CBD) and then thermally annealed them at 400 °C [...] Read more.

Zinc oxide (ZnO) is a wide bandgap semiconductor with optoelectronic and photocatalytic properties, which depend on its optical, structural, and morphological characteristics. In this study, we synthesized ZnO thin films by chemical bath deposition (CBD) and then thermally annealed them at 400 °C and 600 °C to evaluate the effect of thermal treatments. We characterized their structural, optical, morphological, and chemical properties using X-ray diffraction (XRD), UV–Vis spectroscopy, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The optical bandgap values were 3.20 eV for the as-grown thin films, and 3.23 eV and 3.21 eV after annealing at 400 °C and 600 °C, respectively. SEM micrographs revealed a change from elongated agglomerates in the as-grown thin films to uniform flower-like structures after annealing at 600 °C. XPS analysis confirmed ZnO formation in all samples, and we detected residual precursor species only in the as-grown thin films, which were completely removed by annealing at 600 °C. These results demonstrate that the CBD synthesis of ZnO can tune its optical and morphological properties through thermal annealing, making it suitable for optoelectronic, sensing, and photocatalytic applications. Full article

(This article belongs to the Special Issue Featured Papers in Inorganic Materials 2025)

► Show Figures

Figure 1

21 pages, 1982 KB

Open AccessReview

Use of N-Heterocyclic Carbene Compounds (NHCs) Under Sustainable Conditions—An Update

by Abdelkarim El Qami, Adrien Kibongui-Fila and Sabine Berteina-Raboin

Inorganics 2025, 13(10), 330; https://doi.org/10.3390/inorganics13100330 - 1 Oct 2025

Abstract

In this review, we focused on advances made over the last two decades in the field of catalysis using N-heterocyclic carbenes (NHCs), which can be used for metallic or non-metallic catalysis. We listed the advantages of these NHCs and their modes of [...] Read more.

In this review, we focused on advances made over the last two decades in the field of catalysis using N-heterocyclic carbenes (NHCs), which can be used for metallic or non-metallic catalysis. We listed the advantages of these NHCs and their modes of action in various couplings. With regard to metal catalysis, we have focused here on palladium and nickel catalysis, and then we looked at their use without transition metals. The work mentioned, in this review, only concerns research carried out under sustainable conditions, both in terms of the types of reactions and reaction conditions used (solvents, quantities, accessibility, and easy purification). Full article

(This article belongs to the Special Issue Metal-Catalyzed Cross-Couplings)

► Show Figures

Figure 1

18 pages, 3355 KB

Open AccessArticle

Characterizations of Semiconductive W-Doped Ga₂O₃ Thin Films and Application in Heterojunction Diode Fabrication

by Chia-Te Liao, Yi-Wen Wang, Cheng-Fu Yang and Kao-Wei Min

Inorganics 2025, 13(10), 329; https://doi.org/10.3390/inorganics13100329 - 1 Oct 2025

Abstract

In this study, high-conductivity W-doped Ga₂O₃ thin films were successfully fabricated by directly depositing a composition of Ga₂O₃ with 10.7 at% WO₃ (W:Ga = 12:100) using electron beam evaporation. The resulting thin films were found to [...] Read more.

In this study, high-conductivity W-doped Ga₂O₃ thin films were successfully fabricated by directly depositing a composition of Ga₂O₃ with 10.7 at% WO₃ (W:Ga = 12:100) using electron beam evaporation. The resulting thin films were found to be amorphous. Due to the ohmic contact behavior observed between the W-doped Ga₂O₃ film and platinum (Pt), Pt was used as the contact electrode. Current-voltage (J-V) measurements of the W-doped Ga₂O₃ thin films demonstrated that the samples exhibited significant current density even without any post-deposition annealing treatment. To further validate the excellent charge transport characteristics, Hall effect measurements were conducted. Compared to undoped Ga₂O₃ thin films, which showed non-conductive characteristics, the W-doped thin films showed an increased carrier concentration and enhanced electron mobility, along with a substantial decrease in resistivity. The measured Hall coefficient of the W-doped Ga₂O₃ thin films was negative, indicating that these thin films were n-type semiconductors. Energy-Dispersive X-ray Spectroscopy was employed to verify the elemental ratios of Ga, O, and W in the W-doped Ga₂O₃ thin films, while X-ray photoelectron spectroscopy analysis further confirmed these ratios and demonstrated their variation with the depth of the deposited thin films. Furthermore, the W-doped Ga₂O₃ thin films were deposited onto both p-type and heavily doped p⁺-type silicon (Si) substrates to fabricate heterojunction diodes. All resulting devices exhibited good rectifying behavior, highlighting the promising potential of W-doped Ga₂O₃ thin films for use in rectifying electronic components. Full article

(This article belongs to the Special Issue Advanced Inorganic Semiconductor Materials, 3rd Edition)

► Show Figures

Figure 1

9 pages, 2524 KB

Open AccessFeature PaperArticle

Metalloamination/Cyclization of Zinc(II) Amides Derived from N,N-Dimethylhydrazinoalkenes—Applications for the Direct C-SP² Functionalization of Aryl and Vinyl Electrophiles

by Jérome Lépeule, Christian Frabitore and Tom Livinghouse

Inorganics 2025, 13(10), 328; https://doi.org/10.3390/inorganics13100328 - 30 Sep 2025

Abstract

Treatment of N,N-dimethylhydrazinoalkenes with diethylzinc followed by exposure of the resulting ethylzinc amides to high vacuum drives a Schlenck redistribution metalloamination/cyclization to generate the corresponding bis(organozinc) intermediates in excellent conversions. Direct treatment of these with appropriate aryl or vinyl electrophiles [...] Read more.

Treatment of N,N-dimethylhydrazinoalkenes with diethylzinc followed by exposure of the resulting ethylzinc amides to high vacuum drives a Schlenck redistribution metalloamination/cyclization to generate the corresponding bis(organozinc) intermediates in excellent conversions. Direct treatment of these with appropriate aryl or vinyl electrophiles in the presence of catalytic PdCl₂ (DPEphos) provides the corresponding arylated or alkenylated pyrrolidines and piperidines with high efficiency. Full article

(This article belongs to the Special Issue Metal-Catalyzed Cross-Couplings)

► Show Figures

Graphical abstract

13 pages, 1477 KB

Open AccessArticle

Complexation-Induced Reduction of Cu^II to Cu^I Promoted by a Distorted Tetrahedral N₄-Type Schiff-Base Ligand

by Tomoyuki Takeyama, Daisuke Shirabe, Nobutsugu Hamamoto and Takehiro Ohta

Inorganics 2025, 13(10), 327; https://doi.org/10.3390/inorganics13100327 - 30 Sep 2025

Abstract

Although spontaneous or complexation-induced reductions of Cu^II to Cu^I have occasionally been observed, controlling these processes remains a challenge. Herein, we report the synthesis of Cu^I complexes via the complexation-induced reduction of Cu^II complexes with pyridine-containing N₄ Schiff-base [...] Read more.

Although spontaneous or complexation-induced reductions of Cu^II to Cu^I have occasionally been observed, controlling these processes remains a challenge. Herein, we report the synthesis of Cu^I complexes via the complexation-induced reduction of Cu^II complexes with pyridine-containing N₄ Schiff-base ligand L incorporating a biphenyl unit (L = N,N’-([1,1′-biphenyl]-2,2′-diyl)bis(1-(6-methylpyridin-2-yl)methanimine)). Such a reduction has not yet been observed in previously reported Cu^II complexes with pyridine-containing N₄ Schiff-base ligands, strongly suggesting that the torsional distortion of the ligand framework induced by the biphenyl moiety effectively promotes the complexation-induced reduction of Cu^II to Cu^I. The Cu^I complexes were thoroughly characterized by ¹H NMR spectroscopy, UV–vis–NIR spectroscopy, and single-crystal X-ray diffraction analyses. The [Cu^I(L)]⁺ complex undergoes a reversible redox process with its oxidized species, which was identified as a Cu^II complex based on spectroelectrochemical measurements and theoretical calculations. Full article

(This article belongs to the Special Issue State-of-the-Art Inorganic Chemistry in Japan)

► Show Figures

Figure 1

10 pages, 1879 KB

Open AccessArticle

Temperature-Dependent Degradation of Volatile Organic Compounds Using Ga₂O₃ Photocatalyst

by Dayoun Hong, Jiwon Kwak, Hyeongju Cha, Heejoong Ryou, Sunjae Kim, Wan Sik Hwang and Hyunah Kim

Inorganics 2025, 13(10), 326; https://doi.org/10.3390/inorganics13100326 - 30 Sep 2025

Abstract

Volatile organic compounds (VOCs), including benzene, toluene, and formaldehyde, are hazardous air pollutants that require efficient and sustainable mitigation strategies. Photocatalytic degradation of VOCs offers a promising pathway; however, its performance is strongly influenced by multiple operational parameters. Here, we present a systematic [...] Read more.

Volatile organic compounds (VOCs), including benzene, toluene, and formaldehyde, are hazardous air pollutants that require efficient and sustainable mitigation strategies. Photocatalytic degradation of VOCs offers a promising pathway; however, its performance is strongly influenced by multiple operational parameters. Here, we present a systematic investigation of toluene degradation under ultraviolet-C (UVC) irradiation across controlled temperatures using Ga₂O₃ as a photocatalyst. A comprehensive analysis revealed that elevated temperatures enhanced photocatalytic activity by accelerating chemical reaction rates. However, further temperature increases led to a decrease in performance due to a reduction in the reactant adsorption rate. An optimal operating temperature was identified, at which the balance between chemical reaction rates and reactant adsorption yields the highest degradation efficiency. These findings demonstrate Ga₂O₃ as a promising photocatalyst and provide fundamental insights into the temperature-dependent photocatalytic mechanisms governing VOC removal in practical environmental applications. Full article

(This article belongs to the Special Issue Inorganic Photocatalysts for Environmental Applications)

► Show Figures

Figure 1

21 pages, 6939 KB

Open AccessArticle

Facile Reversible Eu²⁺/Eu³⁺ Redox in Y₂SiO₅ via Spark Plasma Sintering: Dwell Time-Dependent Luminescence Tuning

by Fernando Juárez-López, Merlina Angélica Navarro-Villanueva, Rubén Cuamatzi-Meléndez, Margarita García-Hernández, María José Soto-Miranda and Angel de Jesús Morales-Ramírez

Inorganics 2025, 13(10), 325; https://doi.org/10.3390/inorganics13100325 - 30 Sep 2025

Abstract

The present study investigates the luminescent behaviour of sol–gel derived Y₂SiO₅ powders doped with Eu³⁺ ions, subjected to spark plasma sintering. The sintering process induces the partial reduction of Eu³⁺ to Eu²⁺, and the phenomenon is [...] Read more.

The present study investigates the luminescent behaviour of sol–gel derived Y₂SiO₅ powders doped with Eu³⁺ ions, subjected to spark plasma sintering. The sintering process induces the partial reduction of Eu³⁺ to Eu²⁺, and the phenomenon is strongly dependent on the holding time within the SPS chamber. The luminescent properties are tunable via the initial Eu concentration, holding time and excitation wavelength, resulting in a wide range of emission colours from red (Eu³⁺) at 220 nm excitation to blue (Eu²⁺) at 365 nm, and mixed colours at 257 nm. Moreover, the Eu³⁺/Eu²⁺ redox process is reversible. Overall, the results demonstrate that SPS conditions can be exploited to modulate the valence state of luminescent centres, which is reversible by oxidation under ambient conditions, enabling controlled modulation of the optical properties. Full article

(This article belongs to the Special Issue Rare-Earth Luminescent Materials)

► Show Figures

Figure 1

46 pages, 7793 KB

Open AccessReview

MIL Series in MOFs for the Removal of Emerging Contaminants: Application and Mechanisms

by Yixiang Chen, Yusheng Jiang, Weiping Li, Wei Su, Yi Xing, Shuyan Yu, Wenxin Li, Ying Guo, Duo Zhang, Shanqing Wang, Zhongshan Qian, Chen Hong and Bo Jiang

Inorganics 2025, 13(10), 324; https://doi.org/10.3390/inorganics13100324 - 29 Sep 2025

Abstract

In global economic integration and rapid urbanization, the equilibrium between resource utilization efficiency and ecological preservation is confronted with significant challenges. Emerging contaminants have further exacerbated environmental pressures and posed threats to the ecosystem and human health. Metal–organic frameworks (MOFs) have emerged as [...] Read more.

In global economic integration and rapid urbanization, the equilibrium between resource utilization efficiency and ecological preservation is confronted with significant challenges. Emerging contaminants have further exacerbated environmental pressures and posed threats to the ecosystem and human health. Metal–organic frameworks (MOFs) have emerged as a prominent area of research in ecological remediation, owing to their distinctive porous configuration, substantial specific surface area, and exceptional chemical stability. The Materials Institute Lavoisier (MIL) series (e.g., MIL-53, MIL-88, MIL-100, MIL-101, and MIL-125) has been shown to effectively promote the separation and migration of photogenerated carriers and significantly enhance the degradation of organic contaminants. This property renders it highly promising for the photocatalytic degradation of emerging contaminants. This paper provides a concise overview of the classification, synthesis methods, modification strategies, and application effects of MIL series MOFs in the removal of emerging contaminants. The advantages and limitations of MIL series MOFs in environmental remediation are further analyzed. Particularly, we offer insights and support for innovative strategies in the treatment of emerging contaminants, including POPs, PPCPs, VOCs, and microplastics, contributing to technological innovation and development in environmental remediation. Future development of MOFs includes the optimization of the performance of the MILs, reducing the high synthesis costs of MILs, applying MILs in real-environment scenarios, and accurate detection of degradation products of environmental pollutants. Full article

(This article belongs to the Special Issue Nanocomposites for Photocatalysis, 2nd Edition)

► Show Figures

Figure 1

23 pages, 4574 KB

Open AccessArticle

A Heterobimetallic Au(I)–Ru(II) Complex Bridged by dppb: Synthesis, Structural and Solution Characterization, BSA Interaction and In Vivo Toxicity Evaluation in Wistar Rats

by Adnan Zahirović, Sunčica Roca, Muhamed Fočak, Selma Fetahović, Višnja Muzika, Damir Suljević, Anela Topčagić, Maja Mitrašinović-Brulić, Irnesa Osmanković, Debbie C. Crans and Aleksandar Višnjevac

Inorganics 2025, 13(10), 323; https://doi.org/10.3390/inorganics13100323 - 29 Sep 2025

Abstract

A novel heterobimetallic ruthenium(II)–gold(I) complex featuring a bridging bis(diphenylphosphino)butane (dppb) ligand was prepared and fully characterized. Single-crystal X-ray diffraction revealed a piano-stool geometry around Ru(II) with η⁶-cymene, two chlorido ligands, and one phosphorus atom from dppb, while the Au(I) center adopts [...] Read more.

A novel heterobimetallic ruthenium(II)–gold(I) complex featuring a bridging bis(diphenylphosphino)butane (dppb) ligand was prepared and fully characterized. Single-crystal X-ray diffraction revealed a piano-stool geometry around Ru(II) with η⁶-cymene, two chlorido ligands, and one phosphorus atom from dppb, while the Au(I) center adopts a linear P–Au–Cl coordination. Structural integrity in the solution was confirmed by 1D and 2D NMR spectroscopy, while solution behavior was further monitored by variable solvent ³¹P NMR and UV/Vis spectroscopy, indicating that the organometallic Ru–arene core remains intact, whereas the chlorido ligands coordinated to Ru exhibit partial lability. Complementary characterization included elemental analysis, FTIR, and UV/Vis spectroscopy. Spectrofluorimetric and FRET analyses showed that Au(dppb), Ru(dppb), and the heterobimetallic AuRu complex bind to BSA with apparent constants of 1.41 × 10⁵, 5.12 × 10², and 2.66 × 10⁴ M⁻¹, respectively, following a static quenching mechanism. In vivo biological evaluation in Wistar rats revealed no significant hepatotoxicity or nephrotoxicity, with only mild and reversible histological alterations and preserved hepatocyte nuclear morphology. Hematological analysis indicated a statistically significant reduction in leukocyte populations, suggesting immunomodulatory potential, while elevated serum glucose levels point to possible endocrine or metabolic activity. These findings highlight compound structural stability and intriguing bioactivity profile, making it a promising platform for further organometallic drug development and testing. Full article

(This article belongs to the Special Issue Editorial Board Members’ Collection Series in “Featuring Ligands and Their Applications in Coordination Chemistry”, 2nd Edition)

► Show Figures

Figure 1

15 pages, 3394 KB

Open AccessReview

Progress and Prospect of Sm-Fe-N Magnets

by Tetsuji Saito

Inorganics 2025, 13(10), 322; https://doi.org/10.3390/inorganics13100322 - 29 Sep 2025

Abstract

High-performance but expensive neodymium-iron-boron (Nd-Fe-B) magnets are widely used in automotive and electrical applications. Prospective candidates for rare-earth-free magnets include Fe-based magnets such as L1₀-FeNi and α″-Fe₁₆N₂ phase. However, these rare-earth-free magnets cannot replace Nd-Fe-B magnets due to [...] Read more.

High-performance but expensive neodymium-iron-boron (Nd-Fe-B) magnets are widely used in automotive and electrical applications. Prospective candidates for rare-earth-free magnets include Fe-based magnets such as L1₀-FeNi and α″-Fe₁₆N₂ phase. However, these rare-earth-free magnets cannot replace Nd-Fe-B magnets due to their lower coercivity. Thus, the development of Sm-based magnets, using the relatively abundant rare-earth element Sm, has become a focus of attention. A promising, cheaper alternative with excellent magnetic properties is the Samarium-iron-nitride (Sm-Fe-N) magnet. This paper describes the production and magnetic properties of Sm-Fe-N powders with Th₂Zn₁₇ and TbCu₇ phases. The production process and magnetic properties of Sm-Fe-N bonded magnets prepared from the powders are also described. Current approaches for producing Sm-Fe-N sintered magnets are included. Full article

► Show Figures

Figure 1

34 pages, 6474 KB

Open AccessReview

Review on Chemistry of Water-Containing Calcium Carbonates and Their Transformations into Amorphous and Crystalline Carbonate Modifications

by Kende Attila Béres, Péter Németh and László Kótai

Inorganics 2025, 13(10), 321; https://doi.org/10.3390/inorganics13100321 - 28 Sep 2025

Abstract

Calcium carbonate (CaCO₃) is a dominant component of sedimentary rocks and biogenic structures, and is one of the most frequently studied inorganic compounds. It also plays a key role in preparing modern engineered materials. CaCO₃ has three well-known polymorphs, calcite, [...] Read more.

Calcium carbonate (CaCO₃) is a dominant component of sedimentary rocks and biogenic structures, and is one of the most frequently studied inorganic compounds. It also plays a key role in preparing modern engineered materials. CaCO₃ has three well-known polymorphs, calcite, aragonite, and vaterite, and four solvatomorphs with diverse crystallographic arrangements, hydration states, reactivity, and stability. Its solvatomorphs include the variable water-containing amorphous calcium carbonate (ACC—CaCO₃·xH₂O) and the crystalline monohydrocalcite (MHC—CaCO₃·H₂O), calcium carbonate hexahydrate (ikaite—CaCO₃·6H₂O), and the recently reported hemihydrate (CCHH—CaCO₃·0.5H₂O). Here, we review the preparation, crystal structure, and properties of these solvatomorphs and discuss their mutual transformations. Full article

(This article belongs to the Special Issue Metal Carbonates—from Amorphous Carbonates to Carbonate Complexes)

► Show Figures

Figure 1

21 pages, 5252 KB

Open AccessArticle

Photoactive TiO₂ Nanotubes and SILAR-Synthesized PbS/TiO₂ Heterojunctions for Tetracycline Antibiotic Photodegradation

by Safa Jemai, Karim Choubani, Anouar Hajjaji, Syrine Sassi, Mohamed Ben Rabha, Mohammed A. Almeshaal, Bernabé Mari Soucase and Brahim Bessais

Inorganics 2025, 13(10), 320; https://doi.org/10.3390/inorganics13100320 - 27 Sep 2025

Abstract

Titanium dioxide nanotubes (TiO₂ NTs) decorated with lead sulfide nanoparticles (PbS NPs) were synthesized using the Successive Ionic Layer Adsorption and Reaction (SILAR) method at different number (n) of cycles (where n = 3, 5, and 8) and evaluated for [...] Read more.

Titanium dioxide nanotubes (TiO₂ NTs) decorated with lead sulfide nanoparticles (PbS NPs) were synthesized using the Successive Ionic Layer Adsorption and Reaction (SILAR) method at different number (n) of cycles (where n = 3, 5, and 8) and evaluated for tetracycline (TC) photodegradation under UV light. PbS NPs/TiO₂ NTs heterojunctions prepared with 5 SILAR cycles showed optimal photocatalytic activity. Also, under optimized conditions, pure TiO₂ NTs achieved complete TC photodegradation (99%) within 5 h under UV irradiation, with a proposed degradation mechanism based on holes (h⁺) and hydroxyl radicals (•OH) as dominant reactive species. Full article

(This article belongs to the Special Issue Advances in Inorganic–Organic Composite Photocatalysts for Energy and Environmental Applications)

► Show Figures

Figure 1

30 pages, 5345 KB

Open AccessReview

Recent Advances in Graphitic Carbon Nitride-Based Materials in the Photocatalytic Degradation of Emerging Contaminants

by Dan Xu, Heshan Cai, Daguang Li, Feng Chen, Shuwen Han, Xiaojuan Chen, Zhenyi Li, Zebang He, Zhuhong Chen, Jiabao He, Weiyu Huang, Xinyi Tang, Yihuan Wen and Yejun Feng

Inorganics 2025, 13(10), 319; https://doi.org/10.3390/inorganics13100319 - 26 Sep 2025

Abstract

The increasing presence of emerging contaminants (ECs) has attracted considerable attention due to their potential harm to human health and ecosystems. Graphitic carbon nitride (g-C₃N₄), a semiconductor devoid of metals, stands out due to its distinctive optical properties and [...] Read more.

The increasing presence of emerging contaminants (ECs) has attracted considerable attention due to their potential harm to human health and ecosystems. Graphitic carbon nitride (g-C₃N₄), a semiconductor devoid of metals, stands out due to its distinctive optical properties and strong resistance to chemical degradation, which holds significant promise in the photocatalytic degradation of ECs. However, the inherent limitations of g-C₃N₄, such as its reduced specific surface area and the swift recombination of photogenerated electron-hole pairs, have prompted extensive research on modification strategies to enhance its photocatalytic performance. Current research on g-C₃N₄-based materials is often constrained in scope, with most reviews focusing solely on modification strategies or its application in degrading a single category of emerging contaminants (ECs). In this review, a systematic overview of synthesis methods and advanced modification strategies for g-C₃N₄-based materials is discussed, highlighting their recent advances in the photocatalytic degradation of various ECs using g-C₃N₄-based materials, which underscores their potential for environmental remediation. Moreover, this article critically examines the current challenges and outlines future research directions, with particular emphasis on integrating artificial intelligence and machine learning to accelerate the development of g-C₃N₄-based photocatalysts and optimize degradation processes, thereby promoting their efficient application in the photocatalytic degradation of ECs. Full article

(This article belongs to the Special Issue Novel Photo(electro)catalytic Degradation)

► Show Figures

Figure 1

15 pages, 3809 KB

Open AccessArticle

Co-Polymerized P(AN-co-IA)-Derived Electrospun Nanofibers with Improved Graphitization via Dual-Metallocene Integration at Low Temperature

by Taewoo Kim, Tae Hoon Ko, Byoung-Suhk Kim, Yong-Sik Chung and Hak Yong Kim

Inorganics 2025, 13(10), 318; https://doi.org/10.3390/inorganics13100318 - 26 Sep 2025

Abstract

In this study, COOH-functionalized co-polymer of acrylonitrile and itaconic acid (P(AN-co-IA)) is synthesized via free radical copolymerization using DMSO as solvent. The continuous non-aligned carbon nanofibers (CNFs) with different amounts of metallocene (zirconocene and ferrocene) are fabricated through electrospinning, followed by a series [...] Read more.

In this study, COOH-functionalized co-polymer of acrylonitrile and itaconic acid (P(AN-co-IA)) is synthesized via free radical copolymerization using DMSO as solvent. The continuous non-aligned carbon nanofibers (CNFs) with different amounts of metallocene (zirconocene and ferrocene) are fabricated through electrospinning, followed by a series of heat treatments under an inert atmosphere. The influence of metallocenes on electrospun carbon nanofiber diameter, alignment, and structural ordering was systematically investigated using FESEM, XRD, Raman spectroscopy, and TEM. Incorporation of dual metallocenes significantly alters the fiber diameter, improves orientation, and promotes graphitic domain formation at 1100 °C, a much lower temperature than conventional graphitization. The optimized sample (Zr-Fe)₁-P(AN-co-IA)-eGNF) exhibited the lowest I_D/I_G ratio compared to pristine and all prepared samples, indicating an improved degree of graphitization due to the uniform distribution of metallocene nanofiber matrix. Furthermore, the electrical conductivity of optimized (Zr-Fe)₁-P(AN-co-IA)-eGNF reached the highest value (1654.5 S/m) due to the high degree of graphitization of carbon nanofibers. These results show that integrating dual metallocene is an efficient pathway for tailoring nanofiber morphology and achieving conductive, structurally ordered electrospun eGNFs at reduced temperatures, with potential applications in various fields. Full article

(This article belongs to the Special Issue Carbon-Based Hybrid Materials for Environmental and Energy Applications)

► Show Figures

Graphical abstract

13 pages, 25357 KB

Open AccessArticle

Low-Temperature Formation of Aluminum Nitride Powder from Amorphous Aluminum Oxalate via Carbothermal Reduction

by Wenjing Tang, Yaling Yu, Zixuan Huang, Weijie Wang, Shaomin Lin, Ji Luo, Chenyang Zhang and Zhijie Zhang

Inorganics 2025, 13(10), 317; https://doi.org/10.3390/inorganics13100317 - 25 Sep 2025

Abstract

Aluminum nitride (AlN) powder, a cornerstone material for advanced ceramics. This study examines the low-temperature formation of AlN crystals as well as their phase transformation by employing amorphous aluminum oxalate (AAO) as a novel precursor for carbothermal reduction, contrasting it with conventional aluminum [...] Read more.

Aluminum nitride (AlN) powder, a cornerstone material for advanced ceramics. This study examines the low-temperature formation of AlN crystals as well as their phase transformation by employing amorphous aluminum oxalate (AAO) as a novel precursor for carbothermal reduction, contrasting it with conventional aluminum hydroxide (Al(OH)₃). Through characterization using X-ray diffraction (XRD), scanning electron microscopy (SEM), High-Resolution Transmission Electron Microscope (HRTEM), ²⁷Al Magic-Angle Spinning Nuclear Magnetic Resonance (²⁷Al-MAS-NMR) energy-dispersive spectroscopy (EDS), and Fourier-transform infrared spectroscopy (FTIR), we unraveled the phase evolution pathways and the formation of AlN. Key findings reveal striking differences between the two precursors. When Al(OH)₃ was used, no AlN phase was detected at 1350 °C, and even at 1500 °C, the AlN obtained with significant residual alumina impurities. In contrast, the AAO precursor demonstrated exceptional efficiency: nano-sized α-Al₂O₃ formed at 1050 °C, followed by the emergence of AlN phases at 1200 °C, ultimately gaining the pure AlN at 1500 °C. The phase transformation sequence—Al(OH)₃ → γ-Al₂O₃ (950 °C) → (α-Al₂O₃ + δ-Al₂O₃) (1050 °C) → (AlN + α-Al₂O₃) (1200 °C~ 1350 °C) → AlN (≥1500 °C)—highlights the pivotal role of nano-sized α-Al₂O₃ in enabling low-temperature nano AlN synthesis. By leveraging the unique properties of AAO, we offer a transformative strategy for synthesizing nano-sized AlN powders, with profound implications for the ceramics industry. Full article

(This article belongs to the Special Issue New Advances into Nanostructured Oxides, 3rd Edition)

► Show Figures

Figure 1

10 pages, 2681 KB

Open AccessArticle

Theoretical Study on the Ortho–Para Reactivity Difference in Ru-Catalyzed Amination of Aminopyridines via η⁶-Coordination: Role of Meisenheimer Intermediate Coordination Ability

by Cheng Wang, Shuo-Qing Zhang and Xin Hong

Inorganics 2025, 13(10), 316; https://doi.org/10.3390/inorganics13100316 - 25 Sep 2025

Abstract

η⁶-Coordination catalysis has emerged as an effective strategy for activating electron-rich (hetero)arenes toward nucleophilic substitution. Recent experimental studies on Ru(II)-catalyzed amination of aminopyridines revealed a striking ortho–para reactivity difference, with ortho-substituted substrates undergoing efficient amination while para analogs [...] Read more.

η⁶-Coordination catalysis has emerged as an effective strategy for activating electron-rich (hetero)arenes toward nucleophilic substitution. Recent experimental studies on Ru(II)-catalyzed amination of aminopyridines revealed a striking ortho–para reactivity difference, with ortho-substituted substrates undergoing efficient amination while para analogs are unreactive under identical conditions. Herein, we present a density functional theory investigation to elucidate the origin of this divergence. Computed free-energy profiles show that both substitution patterns follow a similar stepwise mechanism involving Ru-bound Meisenheimer intermediates and a proton-transfer relay, with C–N bond cleavage/rearomatization as the rate-determining step. However, the para pathway suffers from a substantially higher overall barrier, originating from the intrinsically less stable Meisenheimer intermediates. Energy decomposition analysis indicates that the decisive factor is weaker orbital interaction between the CpRu(II) fragment and the para-substituted Meisenheimer intermediate, whereas electrostatics and dispersion play negligible roles. These findings highlight the key role of metal–substrate orbital interactions in stabilizing dearomatized intermediates, offering mechanistic insights for rational design of η⁶-coordination catalysis with enhanced reactivity and selectivity. Full article

(This article belongs to the Special Issue Transition Metal Catalysts: Design, Synthesis and Applications)

► Show Figures

Figure 1

19 pages, 2194 KB

Open AccessArticle

Hidden Magnetic-Field-Induced Multiferroic States in A-Site-Ordered Quadruple Perovskites RMn₃Ni₂Mn₂O₁₂: Dielectric Studies

by Alexei A. Belik, Ran Liu and Kazunari Yamaura

Inorganics 2025, 13(10), 315; https://doi.org/10.3390/inorganics13100315 - 25 Sep 2025

Abstract

The appearance of spin-induced ferroelectric polarization in the so-called type-II multiferroic materials has received a lot of attention. The nature and mechanisms of such polarization were intensively studied using perovskite rare-earth manganites, RMnO₃, as model systems. Later, multiferroic properties were discovered [...] Read more.

The appearance of spin-induced ferroelectric polarization in the so-called type-II multiferroic materials has received a lot of attention. The nature and mechanisms of such polarization were intensively studied using perovskite rare-earth manganites, RMnO₃, as model systems. Later, multiferroic properties were discovered in some RFeO₃ perovskites and possibly in some RCrO₃ perovskites. However, R₂NiMnO₆ double perovskites have ferromagnetic structures that do not break the inversion symmetry. It was found recently that more complex magnetic structures are realized in A-site-ordered quadruple perovskites, RMn₃Ni₂Mn₂O₁₂. Therefore, they have the potential to be multiferroics. In this work, dielectric properties in magnetic fields up to 9 T were investigated for such perovskites as RMn₃Ni₂Mn₂O₁₂ with R = Ce to Ho and for BiMn₃Ni₂Mn₂O₁₂. The samples with R = Bi, Ce, and Nd showed no dielectric anomalies at all magnetic fields, and the dielectric constant decreases with decreasing temperature. The samples with R = Sm to Ho showed qualitatively different behavior when the dielectric constant started increasing with decreasing temperature below certain temperatures close to the magnetic ordering temperatures, T_N. This difference could suggest different magnetic ground states. The samples with R = Eu, Dy, and Ho still showed no anomalies on the dielectric constant. On the other hand, peaks emerged at T_N on the dielectric constant in the R = Sm sample from about 2 T up to the maximum available field of 9 T. The Gd sample showed peaks on dielectric constant at T_N between about 1 T and 7 T. Transition temperatures increase with increasing magnetic fields for R = Sm and decrease for R = Gd. These findings suggest the presence of magnetic-field-induced multiferroic states in the R = Sm and Gd samples with intermediate ionic radii. Dielectric properties at different magnetic fields are also reported for Lu₂NiMnO₆ for comparison. Full article

(This article belongs to the Special Issue Recent Progress in Perovskites)

► Show Figures

Graphical abstract

13 pages, 2257 KB

Open AccessArticle

Scalable High-Yield Exfoliation of Hydrophilic h-BN Nanosheets via Gallium Intercalation

by Sungsan Kang, Dahun Kim, Seonyou Park, Sung-Tae Lee, John Hong, Sanghyo Lee and Sangyeon Pak

Inorganics 2025, 13(10), 314; https://doi.org/10.3390/inorganics13100314 - 25 Sep 2025

Abstract

Hexagonal boron nitride (h-BN) possesses a unique combination of a wide bandgap, high thermal conductivity, and chemical inertness, making it a key insulating and thermal management material for advanced electronics and nanocomposites. However, its intrinsic hydrophobicity and strong interlayer van der Waals forces [...] Read more.

Hexagonal boron nitride (h-BN) possesses a unique combination of a wide bandgap, high thermal conductivity, and chemical inertness, making it a key insulating and thermal management material for advanced electronics and nanocomposites. However, its intrinsic hydrophobicity and strong interlayer van der Waals forces severely limit exfoliation efficiency and dispersion stability, particularly in scalable liquid-phase processes. Here, we report a synergistic exfoliation strategy that integrates acid-induced hydroxylation with gallium (Ga) intercalation to achieve high-yield (>80%) production of ultrathin (<4 nm) hydrophilic h-BN nanosheets. Hydroxylation introduces abundant -OH groups, expanding interlayer spacing and significantly increasing surface polarity, while Ga intercalation leverages its native Ga₂O₃ shell to form strong interfacial interactions with hydroxylated basal planes. This oxide-mediated adhesion facilitates efficient layer separation under mild sonication, yielding nanosheets with well-preserved lateral dimensions and exceptional dispersion stability in polar solvents. Comprehensive characterization confirms the sequential chemical and structural modifications, revealing the crucial roles of hydroxylation-induced activation and Ga₂O₃ assisted wettability enhancement. This combined chemical activation–soft metallic intercalation approach provides a scalable, solution-processable route to high-quality h-BN nanosheets, opening new opportunities for their integration into dielectric, thermal interface, and multifunctional composite systems. Full article

(This article belongs to the Special Issue Physicochemical Characterization of 2D Materials)

► Show Figures

Figure 1

Journal Description

Inorganics

Latest Articles

Journal Menu

Journal Browser

Highly Accessed Articles

Latest Books

E-Mail Alert

News

Topics

Conferences

Special Issues

Topical Collections

Further Information

Guidelines

MDPI Initiatives

Follow MDPI