Electrochemical Biomass Upgrading Coupled with Hydrogen Production under Industrial-level Current Density.

Abstract

As promising hydrogen energy carrier, formic acid (HCOOH) plays the indispensable roles in building a complete industry chain of a hydrogen economy. Currently, the biomass upgrading assisted water electrolysis has emerged as an attractive alternative for co-producing green HCOOH and H2 in a cost-effective manner, yet simultaneously affording high current density and Faradaic efficiency (FE) still remains a big challenge. Here we report a ternary NiVRu-layered double hydroxides (LDHs) nanosheet arrays for selective glycerol oxidation and hydrogen evolution catalysis, which yields an industry-level 1 A cm-2 at voltage of 1.933V, meanwhile showing considerable HCOOH and H2 productivities of 12.5 and 17.9mmol cm-2 h-1 , with FEs of almost 80% and 96%, respectively. Experimental and theoretical results reveal that the introduced Ru atoms could tune the local electronic structure of Ni-based LDHs, which not only optimizes hydrogen adsorption kinetics for HER, but also reduces the reaction energy barrier for both the conversion of NiII into GOR-active NiШ and carbon-carbon (C-C) bond cleavage. In short, this work highlights the potential of large-scale H2 and HCOOH productions from integrated electrocatalytic system, and provides new insights for designing advanced electrocatalyst for low-cost and sustainable energy conversion. This article is protected by copyright. All rights reserved.