Advances and Recent Trends in Heterogeneous Photo(Electro)-Catalysis for Solar Fuels and Chemicals

Molecules

James Highfield¹ 

[1] Heterogeneous Catalysis, Institute of Chemical & Engineering Sciences (ICES, A * Star), 1 Pesek Road, Jurong Island, 627833, Singapore; E-Mail

关键词: solar fuels;    heterogeneous photocatalysis;    water splitting;    renewable hydrogen;    visible sensitization;    hydrogen peroxide;    bio-oxygenates photoreforming;    electrocatalysis;    carbon dioxide reduction;   

DOI  :  10.3390/molecules20046739

来源: mdpi

【 摘 要 】

In the context of a future renewable energy system based on hydrogen storage as energy-dense liquid alcohols co-synthesized from recycled CO₂, this article reviews advances in photocatalysis and photoelectrocatalysis that exploit solar (photonic) primary energy in relevant endergonic processes, viz., H₂ generation by water splitting, bio-oxygenate photoreforming, and artificial photosynthesis (CO₂ reduction). Attainment of the efficiency (>10%) mandated for viable techno-economics (USD 2.00–4.00 per kg H₂) and implementation on a global scale hinges on the development of photo(electro)catalysts and co-catalysts composed of earth-abundant elements offering visible-light-driven charge separation and surface redox chemistry in high quantum yield, while retaining the chemical and photo-stability typical of titanium dioxide, a ubiquitous oxide semiconductor and performance “benchmark”. The dye-sensitized TiO₂ solar cell and multi-junction Si are key “voltage-biasing” components in hybrid photovoltaic/photoelectrochemical (PV/PEC) devices that currently lead the field in performance. Prospects and limitations of visible-absorbing particulates, e.g., nanotextured crystalline α-Fe₂O₃, g-C₃N₄, and TiO₂ sensitized by C/N-based dopants, multilayer composites, and plasmonic metals, are also considered. An interesting trend in water splitting is towards hydrogen peroxide as a solar fuel and value-added green reagent. Fundamental and technical hurdles impeding the advance towards pre-commercial solar fuels demonstration units are considered.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.