Electrooxidation of 5-Hydroxymethylfurfural via NiP-NiSe Heterostructure Nanosheet Arrays.

The electrooxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) has been deeply investigated. However, developing a durable electrocatalyst for fast production of FDCA at low potentials remains a challenge. Herein, we report NiP-NiSe heterostructure nanosheet arrays as efficient electrocatalysts for HMF electrooxidation. These nanosheet arrays were synthesized via an in situ deep eutectic solvent etching approach, followed by phosphorization and a selenization process. The optimal NiP-NiSe electrocatalyst could achieve 99.1% FDCA selectivity, 98.9% Faradaic efficiency, and 100% HMF conversion at 1.38 V (reversible hydrogen electrode) within 1.6 h. Density functional theory calculations demonstrate that apparent charge redistribution occurs at the NiP/NiSe heterointerface, which greatly enhances HMF adsorption and consequently modulates the catalytic performance. In situ Raman spectroscopy technology confirms that NiOOH is the main active species during HMF electrooxidation. This work provides a significant strategy to develop robust heterogeneous electrocatalyst for HMF electrooxidation and beyond.