Both water and energy are key sustainability issues that need to be addressed. To this end, photocatalysis is advantageous not only for expediting environmental remediation but also for energy generation. However, the development of novel functional materials and the lack of understanding of the influences in the photocatalytic reaction are still key technical barriers impeding the commercialization of photocatalytic technology. MacRitchie reservoir park in Singapore (left) and straits of Singapore (right). Credit: Hou Wang Three dimensional (3D)...