Scaled‐Up Synthesis of Amorphous NiFeMo Oxides and Their Rapid Surface Reconstruction for Superior Oxygen Evolution Catalysis

• DOI: 10.1002/anie.201909939
• Publication Date: 2019-08-16T12:35:19Z
• Authors: Yu Duan; Zi‐You Yu; Shao‐Jin Hu; Xu‐Sheng Zheng; Chu‐Tian Zhang; Hong‐He Ding; Bi‐Cheng Hu; Qi‐Qi Fu; Zhi‐Long Yu; Xiao Zheng; Jun‐Fa Zhu; Min‐Rui Gao; Shu‐Hong Yu
• Keywords: 02 engineering and technology; 0210 nano-technology; 7. Clean energy; 01 natural sciences; 0104 chemical sciences

AbstractThe anode oxygen evolution reaction (OER) is known to largely limit the efficiency of electrolyzers owing to its sluggish kinetics. While crystalline metal oxides are promising as OER catalysts, their amorphous phases also show high activities. Efforts to produce amorphous metal oxides have progressed slowly, and how an amorphous structure benefits the catalytic performances remains elusive. Now the first scalable synthesis of amorphous NiFeMo oxide (up to 515 g in one batch) is presented with homogeneous elemental distribution via a facile supersaturated co‐precipitation method. In contrast to its crystalline counterpart, amorphous NiFeMo oxide undergoes a faster surface self‐reconstruction process during OER, forming a metal oxy(hydroxide) active layer with rich oxygen vacancies, leading to superior OER activity (280 mV overpotential at 10 mA cm−2 in 0.1 m KOH). This opens up the potential of fast, facile, and scale‐up production of amorphous metal oxides for high‐performance OER catalysts.