Electrocatalytic upgrading of biomass-derived isobutanol to isobutyric acid over NiCo layered double hydroxide nanosheets

Abstract

The electrocatalytic upcycling of biomass-derived platform molecules into value-added chemicals provides a sustainable pathway for transitioning toward a circular bioeconomy. Nickel–cobalt layered double hydroxide nanosheets supported on nickel foam (NiCo-LDH/NF) were successfully fabricated as electrocatalysts for the selective conversion of isobutanol (IBA) to isobutyric acid (IBAc) under mild conditions. The optimized catalyst exhibits a three-dimensional hierarchical nanosheet architecture with an enlarged electrochemically accessible surface area and favorable charge-transfer behavior. Benefiting from the interconnected network and altered electronic structure between the Ni and Co species, NiCo-LDH/NF achieved a Faradaic efficiency of 91.3% and selectivity of 93.2% toward IBAc at 1.52 V vs. RHE. Electrochemical analyses indicated improved IBA oxidation kinetics compared with those of the corresponding monometallic hydroxide catalysts. Mechanistic studies supported a sequential oxidation pathway from IBA to IBAc via adsorbed isobutyraldehyde intermediates. This study demonstrates the potential of bimetallic LDH electrocatalysts for the selective upgrading of biomass-derived alcohols.

Graphical abstract

Keywords

biomass valorization / electrocatalysis / isobutanol electrooxidation / NiCo-LDH / isobutyric acid

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