Beyond Artificial Photosynthesis: Prospects on Photobiorefinery

Abstract

Artificial photosynthesis (AP) technology which integrates solar energy harvesting and chemical conversion process into one device is a promising solution to both global energy and environmental crises. Despite decades of research, AP for solar hydrogen production and CO2 reduction remains in the technological infancy. The low profit margins of the targeted products, the highly energy‐intensive process, and the engineering impracticality have kept AP technology in the laboratory demonstration stage. Photobiorefinery, a photocatalytic process for biomass valorization, has emerged as a new promising application for AP technology. This process offers high‐value products, requires less energy, and potentially could utilize AP process to enhance selectivity. In this Minireview, the recent progress in photocatalytic biomass depolymerization, partial oxidation, hydrogenolysis, and hydrogenation are featured. Challenges and prospects of the photocatalytic biomass valorization towards commercialization are also discussed.

Valorization of Biomass-Derived Platform Molecules via Photoredox Sustainable Catalysis

“…In addition to lignocellulosic biomass, photocatalytic transformation of biomass-relevant alcohols is highly appealing for obtaining usable chemicals [48][49][50], which are pivotal [36]. Copyright 2017 American Chemi-cal Society.…”

Coproduction of hydrogen and lactic acid from glucose photocatalysis on band-engineered Zn1-xCdxS homojunction

“…There has been growing interest in developing a “biorefinery” platform as opposed to the century-old petroleum refinery analogous for sustainable production of fuels and chemicals ( Ragauskas, et al., 2006 ) Unfortunately, two technologically advanced biorefinery platforms, including the thermochemical processes (such as combustion, pyrolysis, and gasification) and biological processes (such as enzymatic hydrolysis and micro-organisms fermentation) are facing setbacks due to carbon-intensive and expensive processes involved therein ( Huber, et al., 2006 ; Rubin, 2008 ). Among other emerging routes, solar-driven biomass photocatalysis (the so-called photo-biorefinery) is appealing to realize solar energy storage into chemical bonds with high energy density( Butburee, et al., 2020 ; Zhao, et al., 2021 ; Wu et al., 2020a , 2020b ; Wu, et al., 2017 ; Zhang et al., 2017a , 2017b ). As one of the most abundant biomass-based compounds, glucose has been utilized to produce various value-added chemicals like glucaric acid, gluconic acid, 5-hydroxymethylfurfural, and lactic acid( Liu et al., 2020a , 2020b ; Zhang and Huber, 2018 ).…”

Photocatalytic hydrogen evolution from biomass conversion

“…Hydrogen production from photocatalytic water splitting (without biomass) is achievable, but at a very low quantum yield (~ 1.8%) due to a thermodynamic barrier and multi-electron transfer process [ 11 ], while quantum yield of photobiorefinary for H 2 production is achievable above 70% [ 12 ]. The photocatalytic reforming of biomass and biomass-derived substrates is energetically comparable to the overall water splitting process, except biomass replaces water as the electron and proton source, as shown in Fig.…”