AUTHOR=Xu Yi-Jun TITLE=Promises and Challenges in Photocatalysis JOURNAL=Frontiers in Catalysis VOLUME=1 YEAR=2021 URL=https://www.frontiersin.org/journals/catalysis/articles/10.3389/fctls.2021.708319 DOI=10.3389/fctls.2021.708319 ISSN=2673-7841