Bicontinuous nanoporous Ni-Fe alloy as a highly active catalyst for hydrazine electrooxidation

Development of highly efficient, durable and cost-effective catalysts for the hydrazine electrooxidation reaction (HzOR) is the key to successful implementation of direct hydrazine fuel cell (DHFC) as a commercially viable power source for vehicular or mobile applications. We herein report the fabrication of a Ni-foam-supported bicontinuous nanoporous Ni-Fe alloy using a hydrothermal method in combination with reductive calcination. The thus-prepared Ni-Fe/NF catalyst shows high activity, good stability and a close to 100% selectivity for the complete electrooxidation of hydrazine following the four-electron pathway, and its overall catalytic performance is comparable to the best level of HzOR catalysts. Our study demonstrates that alloying Ni with Fe could significantly improve the HzOR activity and meanwhile inhibit the non-faradaic hydrazine decomposition. Interestingly, the cheapest Fe appears more effective than many other transition metals in improving the catalytic performance of Ni-based HzOR catalysts. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

This study reports the fabrication of a Ni-Fe alloy catalyst using a hydrothermal method and reductive calcination, which exhibits high activity, good stability, and close to 100% selectivity for the electrooxidation of hydrazine. The overall catalytic performance of the Ni-Fe alloy catalyst is comparable to that of other high-efficiency catalysts.