CuO nanoparticles were synthesized by alcohol-assisted hydrothermal method at various pH values, using sodium hydroxide as a precursor for pH control. The chemical composition, morphological and structural properties of the obtained CuO nanoparticles were investigated by the Raman and energy-dispersive X-ray spectroscopies, the field-emission scanning electron microscopy, and the X-ray diffraction. | Communications in Physics Vol. 33 No. 4 2023 pp. 435-446 DOI https 0868-3166 18283 CuO nanoparticles prepared by alcohol-assisted hydrothermal synthesis for gas-sensing application effect of pH value Nguyen Manh Hung1 Phung Dinh Hoat2 Pham Tien Hung2 Nguyen Van Hoang1 1 Department of Materials Science and Engineering Le Quy Don Technical University Hanoi 100000 Vietnam 2 Department of Physics Le Quy Don Technical University Hanoi 100000 Vietnam E-mail hungnm@ Received 22 April 2023 Accepted for publication 21 November 2023 Published 6 December 2023 Abstract. CuO nanoparticles were synthesized by alcohol-assisted hydrothermal method at vari- ous pH values using sodium hydroxide as a precursor for pH control. The chemical composition morphological and structural properties of the obtained CuO nanoparticles were investigated by the Raman and energy-dispersive X-ray spectroscopies the field-emission scanning electron mi- croscopy and the X-ray diffraction. The results reveal that although the pH value does not affect the formation of the CuO phase it strongly influences the crystalline size the morphology and the particle-agglomeration level of CuO. The differences in the morphology and the crystalline size of CuO nanoparticles are ascribed to various H OH- ratios of the growth solution. Meanwhile with the optimized particle size the CuO nanoparticles-based sensor can be used as a potential candidate for CO and or H2 detection. Keywords alcohol-assisted hydrothermal agglomeration CuO pH control H2 detection. Classification numbers . 1. Introduction Cupric oxide CuO nanoparticles have attracted a lot of interest from scientists around the world due to their special properties. It is well-known that CuO nanoparticles could be widely utilized for different applications including magnetic recording 1 photoelectrochemical water splitting 2 energy conversion 3 catalyst 4 and gas sensors 5 . In these applications CuO 2023 Vietnam .
