NiO has been found to be highly outstanding in producing H
2 and O
2 from H
2O through magnetic stirring, while its capability for the reduction of CO
2 through mechanical stimulation has not been investigated. Presently, NiO particles have been
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NiO has been found to be highly outstanding in producing H
2 and O
2 from H
2O through magnetic stirring, while its capability for the reduction of CO
2 through mechanical stimulation has not been investigated. Presently, NiO particles have been employed to promote the conversion of H
2O and CO
2 enclosed in reactors into flammable gases through magnetic stirring. For a 150 mL glass reactor filled with 50 mL water, 1.00 g of NiO particles, and 1 atm of CO
2, 24 h of magnetic stirring using a home-made Teflon magnetic rotary disk resulted in the formation of 33.80 ppm CO, 10.10 ppm CH
4, and 12,868.80 ppm H
2. More importantly, the reduction of CO
2 was found to be substantially enhanced through coating some polymers and metals on the reactor bottoms, including 25.64 ppm CO and 70.97 ppm CH
4 obtained for a PVC-coated reactor and 30.68 ppm CO, 52.78 ppm CH
4, 3.82 ppm C
2H
6, and 2.18 ppm C
2H
4 obtained for a stainless steel-coated reactor. Hydroxyl radicals were detected using fluorescence spectroscopy for NiO particles under magnetic stirring in water. A tribo-catalytic mechanism has been proposed for the conversion of H
2O and CO
2 into flammable gases by NiO particles under magnetic stirring that is based on the excitation of electron-hole pairs in NiO by mechanical energy absorbed through friction. These findings not only reveal a great potential for mechanical energy to be utilized for CO
2 conversion but are also valuable for fundamental studies.
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