Combining Renewable Electricity and Renewable Carbon: Understanding Reaction Mechanisms of Biomass-Derived Furanic Compounds for Design of Catalytic Nanomaterials.

Abstract

ConspectusDespite the growing deployment of renewable energy conversion technologies, a number of large industrial sectors remain challenging to decarbonize. Aviation, heavy transport, and the production of steel, cement, and chemicals are heavily dependent on carbon-containing fuels and feedstocks. A hopeful avenue toward carbon neutrality is the implementation of renewable carbon for the synthesis of critical fuels, chemicals, and materials. Biomass provides an opportune source of renewable carbon, naturally capturing atmospheric CO2 and forming multicarbon linkages and useful chemical functional groups. The constituent molecules nonetheless require various chemical transformations, often best facilitated by catalytic nanomaterials, in order to access usable final products.Catalyzed transformations of renewable biomass compounds may intersect with renewable energy production by offering a means to utilize excess intermittent electricity and store it within chemical bonds. Electrochemical catalytic processes can often offer advantages in energy efficiency, product selectivity, and modular scalability compared to thermal-driven reactions. Electrocatalytic reactions with renewable carbon feedstocks can further enable related processes such as water splitting, where value-adding organic oxidation reactions may replace the evolution of oxygen. Organic electroreduction reactions may also allow desirable hydrogenations of bonds without intermediate formation of H2 and need for additional reactors.This Account highlights recent work aimed at gaining a fundamental understanding of transformations involving biomass-derived molecules in electrocatalytic nanomaterials. Particular emphasis is placed on the oxidation of biomass derived furanic compounds such as furfural and 5-hydroxymethylfurfural (HMF), which can yield value-added chemicals, including furoic acid (FA), maleic acid (MA), and 2,5-furandicarboxylic acid (FDCA) for renewable materials and other commodities. We highlight advanced implementations of online electrochemical mass spectrometry (OLEMS) and vibrational spectroscopies such as attenuated total reflectance surface enhanced infrared reflection absorption spectroscopy (ATR-SEIRAS), combined with microkinetic models (MKMs) and quantum chemical calculations, to shed light on the elementary mechanistic pathways involved in electrochemical biomass conversion and how these paths are influenced by catalytic nanomaterials. Perspectives are given on the potential opportunities for materials development toward more efficient and selective carbon-mitigating reaction pathways.