Multi‐Site Electrocatalysts Boost pH‐Universal Nitrogen Reduction by High‐Entropy Alloys
Dan Zhang, Huan Zhao, Xueke Wu, Ying Deng, Zuochao Wang, Yi Han, Hongdong Li, Yue Shi, Xilei Chen, Shaoxiang Li, Jianping Lai, Bolong Huang, Lei Wang
Abstract
Abstract Electrocatalytic nitrogen reduction reaction (NRR) has been an important area for many scientists. However, high voltage requirements, low NH 3 yield, and poor stability remain the biggest challenges for NRR. Here, novel high‐entropy alloys RuFeCoNiCu nanoparticles with small size (≈16 nm) and uniformity, prepared in oil phase at atmospheric pressure and low temperature (≤250 °C) are reported for the first time and are applied to NRR. According to the experiments, there is a high NH 3 yield at a low overpotential. It has a surprising NH 3 yield of 57.1 µg h –1 (11.4 µg h –1 cm –2 ) at 0.05 V versus RHE in 0.1 m KOH, and the corresponding Faradaic efficiency reaches 38.5%, which is the electrocatalyst with the highest NH 3 yield at the voltage of 0.05 V versus RHE reported so far. Similarly, the material also exhibits excellent electrochemical properties in other electrolytes such as 0.1 m Li 2 SO 4 , 0.1 m Na 2 SO 4 , and 0.1 m HCl electrolytes. Besides, after the 100 h test, only slightly diminished in activity. Theoretical calculation shows that Fe surrounded by alloy metals is the best site for N 2 adsorption and activation. Co‐Cu and Ni‐Ru couples show an excellent capacity to surface hydrogenation at a low overpotential.