Artificial photosynthesis via solar water splitting provides a promising approach to storing solar energy in the form of hydrogen on a global scale. However, an efficient and cost-effective solar hydrogen production system that can compete with traditional methods using fossil fuels is yet to be developed. A photoelectrochemical (PEC) tandem cell consisting of a p-type photocathode and an n-type photoanode, with the photovoltage provided by the two photoelectrodes, is an attractive route to achieve highly efficient unassisted water splitting at a low cost. In this article, we provide an overview of recent developments of semiconductor materials, including metal oxides, nitrides, chalcogenides, Si, III–V compounds and organics, either as photocathodes or photoanodes for water reduction and oxidation, respectively. In addition, recent efforts in constructing a PEC tandem system for unassisted water splitting are outlined. The importance of developing a single-photon photocathode and photoanode that can deliver high photocurrent in the low bias region for efficient PEC tandem system is highlighted. Finally, we discuss the future development of photoelectrode materials, and viable solutions to realize highly efficient PEC water splitting device for practical applications.
Highlights of 2017
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Welcome to this special 1st anniversary collection for Nano Futures
Welcome to Nano Futures. I am delighted to welcome you to this special collection celebrating Nano Futures' inaugural publication year. Nano Futures was founded in 2017 by Professor Mark Reed and IOP Publishing with the mission of shaping the future of nanoscience by bringing together the latest and most important results and perspectives from across nanoscience and related technologies.
When the journal Nanotechnology was launched over 25 years ago, it pioneered nanoscale science and technology as the first peer-reviewed journal dedicated to the field. Since then, the field has evolved to become one of the most exciting and dynamic areas of research, with the potential to address some of the key challenges of the 21st Century and beyond. Nano Futures aims to publish the ground-breaking work that will help shape this future.
As we open our second volume we have compiled this collection of 11 papers from Volume 1, which highlights the novelty and exceptional standards of Nano Futures. We hope that you enjoy reading these articles and find them useful for your own research. Until the end of 2018 you can access these, and all our published articles for free at www.nano-futures.org.
On behalf of our Editorial Board and IOP Publishing I would like to thank all those who have contributed to the journey so far: authors, referees, editors, and readers. I warmly invite those who aim to actively shape the future of Nanoscience to contribute to Nano Futures. We look forward to the discoveries to come.
Freddy White
Publisher
Nano Futures