Shen Guoqiang, Zhang Rongrong, Pan Lun, Hou Fang, Zhao Yingjie, Shen Zeyu, Mi Wenbo, Shi Chengxiang, Wang Qingfa, Zhang Xiangwen, Zou Ji-Jun
Key Laboratory for Green Chemical Technology of the Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, P. R. China.
Collaborative Innovative Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, P. R. China.
Angew Chem Int Ed Engl. 2020 Feb 3;59(6):2313-2317. doi: 10.1002/anie.201913080. Epub 2019 Dec 17.
Ferric oxides and (oxy)hydroxides, although plentiful and low-cost, are rarely considered for oxygen evolution reaction (OER) owing to the too high spin state (e filling ca. 2.0) suppressing the bonding strength with reaction intermediates. Now, a facile adsorption-oxidation strategy is used to anchor Fe atomically on an ultrathin TiO nanobelt to synergistically lower the spin state (e filling ca. 1.08) to enhance the adsorption with oxygen-containing intermediates and improve the electro-conductibility for lower ohmic loss. The electronic structure of the catalyst is predicted by DFT calculation and perfectly confirmed by experimental results. The catalyst exhibits superior performance for OER with overpotential 270 mV @10 mA cm and 376 mV @100 mA cm in alkaline solution, which is much better than IrO /C and RuO /C and is the best iron-based OER catalyst free of active metals such as Ni, Co, or precious metals.
氧化铁和（羟基）氧化物虽然储量丰富且成本低廉，但由于其自旋态过高（电子填充量约为2.0），抑制了与反应中间体的结合强度，因此很少被用于析氧反应（OER）。现在，一种简便的吸附-氧化策略被用于将铁原子锚定在超薄TiO纳米带上，以协同降低自旋态（电子填充量约为1.08），增强与含氧中间体的吸附，并提高导电性以降低欧姆损耗。通过密度泛函理论（DFT）计算预测了催化剂的电子结构，并通过实验结果得到了完美证实。该催化剂在碱性溶液中表现出优异的OER性能，在10 mA cm时过电位为270 mV，在100 mA cm时过电位为376 mV，远优于IrO /C和RuO /C，是不含镍、钴等活性金属或贵金属的最佳铁基OER催化剂。
