Han Wen-Kai, Wei Jin-Xin, Xiao Kang, Ouyang Ting, Peng Xinwen, Zhao Shenlong, Liu Zhao-Qing
School of Chemistry and Chemical Engineering/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou, No. 230 Wai Huan Xi Road, 510006, P. R. China.
School of Light Industry Science and Engineering, South China University of Technology, Guangzhou, Wushan Street, 510641, P. R. China.
Angew Chem Int Ed Engl. 2022 Aug 1;61(31):e202206050. doi: 10.1002/anie.202206050. Epub 2022 Jun 23.
Despite the fact that high-valent nickel-based oxides exhibit promising catalytic activity for the urea oxidation reaction (UOR), the fundamental questions concerning the origin of the high performance and the structure-activity correlations remain to be elucidated. Here, we unveil the underlying enhanced mechanism of UOR by employing a series of prepared cation-vacancy controllable LiNiO (LNO) model catalysts. Impressively, the optimized layered LNO-2 exhibits an extremely low overpotential at 10 mA cm along with excellent stability after the 160 h test. Operando characterisations combined with the theoretical analysis reveal the activated lattice oxygen in layered LiNiO with moderate cation vacancies triggers charge disproportion of the Ni site to form Ni species, facilitating deprotonation in a lattice oxygen involved catalytic process.
尽管高价镍基氧化物对尿素氧化反应（UOR）表现出有前景的催化活性，但关于其高性能起源和结构-活性相关性的基本问题仍有待阐明。在此，我们通过使用一系列制备的阳离子空位可控的LiNiO（LNO）模型催化剂揭示了UOR潜在的增强机制。令人印象深刻的是，优化后的层状LNO-2在10 mA cm时表现出极低的过电位，并且在160 h测试后具有出色的稳定性。原位表征与理论分析相结合表明，具有适度阳离子空位的层状LiNiO中的活化晶格氧触发了Ni位点的电荷歧化以形成Ni物种，从而在涉及晶格氧的催化过程中促进去质子化。
