Title: | Impact of Al doping on a hydrothermally synthesized beta-Ga(2)O(3) nanostructure for photocatalysis applications |
Author(s): | Kim S; Ryou H; Lee IG; Shin M; Cho BJ; Hwang WS; |
Address: | "Department of Materials Engineering, Korea Aerospace University Goyang 10540 Republic of Korea whwang@kau.ac.kr. Department of Smart Drone Convergence, Korea Aerospace University Goyang 10540 Republic of Korea. Department of Electronics and Information Engineering, Korea Aerospace University Goyang 10540 Republic of Korea. School of Electrical Engineering, Korea Advanced Institute of Science and Technology Daejeon 34141 Republic of Korea" |
ISSN/ISBN: | 2046-2069 (Electronic) 2046-2069 (Linking) |
Abstract: | "Aluminum (Al)-doped beta-phase gallium oxide (beta-Ga(2)O(3)) nanostructures with different Al concentrations (0 to 3.2 at%) are synthesized using a hydrothermal method. The single phase of the beta-Ga(2)O(3) is maintained without intermediate phases up to Al 3.2 at% doping. As the Al concentration in the beta-Ga(2)O(3) nanostructures increases, the optical bandgap of the beta-Ga(2)O(3) increases from 4.69 (Al 0%) to 4.8 (Al 3.2%). The physical, chemical, and optical properties of the Al-doped beta-Ga(2)O(3) nanostructures are correlated with photocatalytic activity via the degradation of a methylene blue solution under ultraviolet light (254 nm) irradiation. The photocatalytic activity is enhanced by doping a small amount of substitutional Al atoms (0.6 at%) that presumably create shallow level traps in the band gap. These shallow traps retard the recombination process by separating photogenerated electron-hole pairs. On the other hand, once the Al concentration in the Ga(2)O(3) exceeds 0.6 at%, the crystallographic disorder, oxygen vacancy, and grain boundary-related defects increase as the Al concentration increases. These defect-related energy levels are broadly distributed within the bandgap, which act as carrier recombination centers and thereby degrade the photocatalytic activity. The results of this work provide new opportunities for the synthesis of highly effective beta-Ga(2)O(3)-based photocatalysts that can generate hydrogen gas and remove harmful volatile organic compounds" |
Notes: | "PubMed-not-MEDLINEKim, Sunjae Ryou, Heejoong Lee, In Gyu Shin, Myunghun Cho, Byung Jin Hwang, Wan Sik eng England 2021/02/12 RSC Adv. 2021 Feb 12; 11(13):7338-7346. doi: 10.1039/d1ra00021g. eCollection 2021 Feb 10" |