Scalable Synthesis of Ir Cluster Anchored on Porous Hollow Carbon Nanobowls for Enhancing pH-Universal Hydrogen Evolution.

Abstract

Design high-loading with superior activity and high atomic efficiency has consistently been a new frontier of heterogeneous catalysis while challenging in synthetic technology. In this work, a universal solid-state strategy is proposed for large scalable production of high-loading Ir clusters on porous hollow carbon nanobowls (Ir CSs/PHCNBs). The strong electronic interaction between metallic Ir cluster and C on PHCNBs leads to electron redistribution, which significantly improves the electron transfer rate on the interface. The obtained Ir CSs/PHCNBs only require overpotentials of 35, 34, and 37mV for the hydrogen evolution reaction (HER) with stable outputting of 10mA cm-2 under acidic, alkaline, and neutral conditions, respectively, which exceeds the state-of-the-art HER electrocatalysts. Meanwhile, the Tafel slopes of Ir CSs/PHCNBs for the HER process are 23.07, 48.76, and 28.95mV dec-1 , greatly lower than that of PHCNBs (152.73, 227.96, and 140.29mV dec-1 ) and commercial Pt/C (20%) (36.33, 66.10, and 36.61mV dec-1 ). These results provide a new strategy for the universal synthesis of clusters catalysts and insight into understanding the interface effects between clusters and carbon substrate, facilitating the industrial application of hydrogen production.