Electrocatalytic Upgrading of Biomass-Derived Intermediate Compounds to Value-Added Products.

The continuous advance in exploring renewable energy resources such as solar and wind will certainly alleviate our reliance on limited fossil reserves. However, the sustainable development of mankind demands not only energy but also carbon-based chemical goods. Unfortunately, exploitation of renewable energy resources like solar and wind will not lead to any carbon-based chemicals. The only sustainable and green carbon source is biomass, the scale of annual production of which has an immense potential to complement that of fossil-derived carbons. To utilize biomass in economically effective ways, many catalytic processes have been investigated. Among various strategies of biomass refinery, electrocatalytic upgrading stands out as an attractive option because of its benign operation conditions, high energy efficiency, and convenient control on production rate and selectivity using electrochemical parameters. This Minireview showcases several electrocatalytic systems for both reductive and oxidative upgrading of representative biomass-derived intermediate compounds, including 5-hydroxymethylfurfural, furfural, levulinic acid, glycerol, and sorbitol to different value-added products. The catalytic routes and mechanisms of each biomass-derived platform compound are discussed and compared. In order to be feasible for large-scale applications, low-cost composition and preparation of electrocatalysts are mandatory and will be emphasized. Finally, our personal perspective on the current challenges and future directions of electrocatalytic biomass upgrading is presented.