Coupling ZnO with carbon materials using a suitable integration method to form ZnO–carbon composites has been established as a promising strategy to ameliorate the photocatalytic performance of semiconductor ZnO. In this perspective article, we describe the recent advances and current status of enhancing the photocatalytic activity and anti-photocorrosion of semiconductor ZnO by coupling with versatile carbon materials, e.g., C₆₀, carbon nanotube, graphene and other carbon materials. The primary roles of carbon materials in boosting the photoactivity and photostability of ZnO have been outlined and illustrated with some selected typical examples. In particular, the three main kinds of mechanisms with regard to anti-photocorrosion of ZnO by coupling with carbon have been demonstrated. Finally, we give a concise perspective on this important research area and specifically propose further research opportunities in optimizing the photocatalytic performance of ZnO–carbon composites and widening the scope of their potential photocatalytic applications.

The expected depletion of fossil fuel reserves and its serious environmental impact have emphasised the issue of sustainable development of the human society. Solar hydrogen by photocatalytic water splitting is a promising alternative to conventional fossil fuels, which is of great potential to relieve the energy and environmental issues and bring an energy revolution in a clean and sustainable manner. This review is going to make a brief introduction of the basic principles of photocatalytic water splitting and the concept of different kinds of water splitting systems. Various engineering strategies for searching higher efficiency of water splitting based on the photocatalytic processes, including light harvesting, charge carriers separation and co-catalysts loading, have been outlined and discussed with selected typical examples on some elaborately designed semiconductor-based photocatalytic systems. Moreover, recent impressive progresses and advancements for photocatalytic water splitting with some promising materials are presented. Finally, this review is concluded with a summary and perspective in this hot area of research.