The reprint "Advances in Heterojunction Photocatalysts" encapsulates pivotal research from a Special Issue of the same name in the journal Catalysts, showcasing advances in sustainable energy and environmental solutions via photocatalysis. This collection of 15 key studies advances our understanding and application of heterojunction photocatalysts-materials designed to efficiently convert solar energy and degrade pollutants due to enhanced charge separation. The reprint includes 13 research articles that cover a broad spectrum of topics, from novel photocatalyst design to the latest advancements in the field. These works showcase not only scientific breakthroughs but also the promising application of heterojunction photocatalysts in areas like environmental remediation and renewable energy generation. Aimed at a diverse audience, the publication serves both as a scientific compendium and a beacon for the potential of photocatalytic materials in fostering a sustainable future. It invites the global scientific community to delve deeper into photocatalysis, continuing the journey of exploration and innovation for societal and environmental improvements.