The　development　of　highly　efficient　photocatalytic　reaction　systems　using　inorganic　and/or　organic　semiconducting　materials　is　highlighted　in　this　book.　Their　design,　construction,　and　optimization,　as　well　as　their　applications　to　environmentally　benign　solar　energy　conversion　systems　for　the　splitting　of　water　to　produce　H2,　the　reduction　of　CO2　and　fixation　of　N2,　and　the　remediation　of　polluted　water,　are　introduced.　A　brief　outline　summarizing　each　of　the　21　chapters　is　also　presented　in　order　to　fully　grasp　the　importance　of　the　research　being　carried　out　on　photocatalytic　materials　for　the　development　of　safe　and　clean　technologies　which　utilize　solar　energy　for　the　twenty-first　century　and　beyond.　©　2023　WILEY-VCH　GmbH.