Recent advances in the electrocatalytic oxidative upgrading of lignocellulosic biomass

Abstract

Lignocellulosic biomass is a critical renewable carbon resource, but most of its utilization is inefficient, and electrocatalytic oxidation is a promising method of upgrading lignocellulose into value-added fuels and chemicals under mild operating conditions. Recently, efforts to enable conversion with a high efficiency and low energy consumption have been reported, but understanding the reaction mechanisms and realizing scaled-up applications of the electrooxidation of lignocellulosic biomass are still in their early stages. A timely overview of recently reported general reaction mechanisms, particularly the strategies developed for use in improving the reaction efficiencies, is necessary to inspire research regarding the highly efficient utilization of lignocellulose. Herein, we summarize the strategies developed to improve electrocatalytic performance in oxidative lignocellulose conversion. The organized summary includes strategies ranging from designing efficient electrocatalysts and adding functional co-catalysts or electrolytes to employing advanced electrolyzers. A comprehensive overview of representative examples should provide universal principles to yield insight into the reaction processes and guide the design of efficient electrocatalytic systems. Finally, the challenges and opportunities in developing the electrocatalytic oxidative upgrading of lignocellulosic biomass in the near future are proposed.

Keywords

Biomass conversion / Lignocellulose / Electrocatalysis / Oxidative upgrading / Electrocatalyst

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

CRediT authorship contribution statement

Yufeng Qi: Writing - original draft. Hairui Guo: Writing - original draft, Data curation. Junting Li: Writing - original draft, Data curation. Li Ma: Writing - original draft, Data curation. Yang Xu: Validation. Huiling Liu: Writing - review & editing, Project administration. Cheng Wang: Supervision. Zhicheng Zhang: Validation, Project administration.

Acknowledgements

This study was supported by the National Natural Science Foundation of China (grant numbers 22275138, 22271219, 22071172, and 22375142).

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