**4. Conclusions**

accumulating

generated by the Peltier module, which

chamber.

 on the top wall. The design

We found that by infusing calcium chloride into a cellulose sponge, faster moisture absorption and an increase in the maximum water uptake capacity (at 27 ◦C and 80% RH) up to ~305% were achieved compared to that without the sponge at ~272%. The sponge inhibited common problems caused by calcium chloride, such as agglomeration and its deliquescence. The approach is simple, and relatively more cost effective compared to other moisture absorber materials. Cellulose sponge as a medium is simple, cheap, and environmentally friendly; energy efficient; and effective when absorbing moisture, as shown by the salt absorbing moisture up to ~305%. A proof-of-concept device was also demonstrated, utilizing a three-channel water collection pathway using a Peltier device to generate the clean water from atmospheric moisture.

**Author Contributions:** Conceptualization, J.L., T.B., E.T., D.J.M. and E.S.; formal analysis, J.L., E.J., and E.S.; investigation, J.L., T.B., E.T. and D.J.M.; writing, J.L., E.J. and E.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by SPH Applied Science Academy Program at Sekolah Pelita Harapan Lippo Village, period 2022–2024.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data presented in this study are available on request from the corresponding author.

**Acknowledgments:** We thank Sekolah Pelita Harapan, Universitas Pelita Harapan and Emmerich Research Center for their generous support in providing lab access throughout this research study.

**Conflicts of Interest:** The authors declare no conflict of interest.
