Synthesis and Characterization of ZnNiIn Layered Double Hydroxides Derived Mixed Metal Oxides with Highly Efficient Photoelectrocatalytic Activities

• Published in: Industrial & engineering chemistry research 2019-01, Vol.58 (2), p.836-848
• Main Authors: Pan, Duo, Ge, Shengsong, Zhao, Junkai, Tian, Jiangyang, Shao, Qian, Guo, Lin, Mai, Xianmin, Wu, Tingting, Murugadoss, Vignesh, Liu, Hu, Ding, Tao, Angaiah, Subramania, Guo, Zhanhu
• Format: Article
• Language: English
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/acs.iecr.8b04829

Visible-light-responsive ZnO/NiO/In2O3 mixed metal oxide (ZNI-MMO) photoelectrocatalysts with different Ni/In molar ratios were derived from corresponding ternary hydrotalcite-like precursors followed by calcination at 600 °C. The as-obtained samples were characterized by XRD, TGA, BET, XPS, SEM, TEM, and UV–vis spectra techniques. The optimal molar ratio of Ni/In was found to be 1:1, where the sample (ZNI-1-MMO) was formed by the aggregation of nanospheres with an average diameter of about 50 nm and a BET specific surface area of 33.80 m2/g. With a 1.5 V bias potential, the ZNI-1-MMO photoelectrode exhibited high photoelectrocatalytic activity toward methylene blue (MB) degradation. The photoelectrocatalytic degradation of MB followed pseudo-first-order kinetics. Radical trapping experiments were conducted to probe the reactive species in the degradation processes. Results indicated that h+ and •OH may be responsible for the efficient MB removal. The photoelectrodegradation mechanism of MB by ZNI-1-MMO-1.5 V photoelectrode was also discussed.