The 2022 solar fuels roadmap

Change log

Abstract: Renewable fuel generation is essential for a low carbon footprint economy. Thus, over the last five decades, a significant effort has been dedicated towards increasing the performance of solar fuels generating devices. Specifically, the solar to hydrogen efficiency of photoelectrochemical cells has progressed steadily towards its fundamental limit, and the faradaic efficiency towards valuable products in CO2 reduction systems has increased dramatically. However, there are still numerous scientific and engineering challenges that must be overcame in order to turn solar fuels into a viable technology. At the electrode and device level, the conversion efficiency, stability and products selectivity must be increased significantly. Meanwhile, these performance metrics must be maintained when scaling up devices and systems while maintaining an acceptable cost and carbon footprint. This roadmap surveys different aspects of this endeavor: system benchmarking, device scaling, various approaches for photoelectrodes design, materials discovery, and catalysis. Each of the sections in the roadmap focuses on a single topic, discussing the state of the art, the key challenges and advancements required to meet them. The roadmap can be used as a guide for researchers and funding agencies highlighting the most pressing needs of the field.


Funder: Alfred P. Sloan Foundation; doi:

Funder: Thistledown Foundation

Funder: Research Corporation for Science Advancement; doi:

Funder: TomKat Foundation; doi:

Funder: Taiwan Ministry of Education and Taiwan and Ministry of Science

Funder: the Netherlands Ministry of Economic Affairs and Climate Policy

Funder: Nederlandse Organisatie voor Wetenschappelijk Onderzoek; doi:

Roadmap, solar fuels, catalysis, CO2 reduction, water splitting
Journal Title
Journal of Physics D: Applied Physics
Conference Name
Journal ISSN
Volume Title
IOP Publishing
Korean Ministry of Science (NRF-2018R1A2A1A05077909, NRF-2019M1A2A2065612)
U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub (DE-SC0021266)
Horizon 2020 Framework Programme (864234, 883264)
National Science Foundation (CBET-1805084)
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (155876, 191299)
Biotechnology and Biological Sciences Research Council (BB/R011923/1, BB/R018413/1)
U.S. Department of Energy (DE-AC36-08GO28308, DE-EE0008092, DE-SC0004993, DE-SC0008707, DE-SC0017619, DE-SC0021173, DE-SC0021266, DE-SC0021953, DE-SC00493)
Lawrence Livermore National Laboratory (19-SI-005, DE-AC52-07NA27344)
Agence Nationale de la Recherche (Labex ARCANE, CBH-EUR-GS, ANR-17-EURE-0003, BEEP)
European Research Council (ERC-2018-CoG BiocatSusChem 819580)
Carlsbergfondet (CF18-0435)
Mohammed bin Salman Center (MbSC2030)
Deutsche Forschungsgemeinschaft (3096/10, 3096/19, 406944504 – SPP 2080, 981)
Japan Society for the Promotion of Science (JP17H06440, JP20H00396)
German Federal Ministry of Education and Research (033RC021A, 033RC021C, 03SF0619C, 03SF0619I)
NSF Chemical Catalysis (1955106)