Superaerophobic CoP Nanowire Arrays as a Highly Effective Anode Electrocatalyst for Direct Hydrazine Fuel Cells

作者：Sun Haoran, Liyao Gao, Anuj Kumar, Zibo Cao, Zheng Chang, Wen Liu, Xiaoming Sun · 发表于：ACS Applied Energy Materials · 年份：2022 · DOI：10.1021/acsaem.2c01005 · 被引用次数：25 · 研究领域：Electrocatalysts for Energy Conversion、Fuel Cells and Related Materials、Advanced battery technologies research

One of the major challenges in developing direct hydrazine fuel cells (DHzFCs) is the creation of highly efficient, robust, and inexpensive electrocatalysts with a superaerophobic property for the hydrazine oxidation reaction (HzOR). Herein, a cobalt phosphide nanowire array ( [email protected] ) is grown on a carbon paper substrate as a highly efficient electrocatalyst for the HzOR in alkaline medium, which features a superaerophobic surface that is highly antigaseous and conducive to nitrogen evolution (a gaseous byproduct of the HzOR). The catalyst demonstrates a significant HzOR performance with an onset potential of −61 mV (vs RHE), an ultralow overpotential of −32 [email protected] mA cm –2, and superior stability with little current density loss over 10,000 s at an overpotential of 0.42 V (vs RHE). The remarkable HzOR performance of the [email protected] catalyst is attributed not only to its high intrinsic activity but also to its nanowire array design, which offers a large specific surface area and rapid electron and mass transfer, as well as its superaerophobic surface wettability to expedite the release of N 2 from the catalyst surface. Furthermore, a DHzFC is constructed using the [email protected] catalyst as the anode and commercial MnO 2 as the cathode, which delivers a high open-circuit voltage of 0.905 V, a remarkable power density of 300 mW cm –2, and 95% retention after 12.5 h operation, suggesting great potential of [email protected] in practical applicati...