Accepted Article Title: Atomically Altered Hematite for Highly Efficient Perovskite Tandem Water Splitting Devices Authors: Gurudayal Gurudayal, Rohit Abraham John, Pablo P Boix, Chenyi Yi, Chen Shi, Mary C Scott, Sjoerd A Veldhuis, Andrew M Minor, Shaik M Zakeer, Lydia Wong, Michael Graetzel, and Nripan Mathews This manuscript has been accepted after peer review and appears as an Accepted Article online prior to editing, proofing, and formal publication of the final Version of Record (VoR). This work is currently citable by using the Digital Object Identifier (DOI) given below. The VoR will be published online in Early View as soon as possible and may be different to this Accepted Article as a result of editing. Readers should obtain the VoR from the journal website shown below when it is published to ensure accuracy of information. The authors are responsible for the content of this Accepted Article. To be cited as: ChemSusChem 10.1002/cssc.201700159 Link to VoR: http://dx.doi.org/10.1002/cssc.201700159
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DOI: 10.1002/((please add manuscript number)) Article type: Communication
Atomically Altered Hematite for Highly Efficient Perovskite Tandem Water Splitting Devices Gurudayal 1, Rohit Abraham John 1, Pablo P Boix 2, Chenyi Yi 3, Chen Shi 2, M.C. Scott 4,5 Sjoerd A. Veldhuis 2, Andrew M. Minor 4,5, S. M. Zakeeruddin 3, Lydia Helena Wong *1, Michael Grätzel 3, and Nripan Mathews *,1,2 1 School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798. 2 Energy Research Institute @NTU (ERI@N), Research Techno Plaza, X-Frontier Block, Level 5, 50 Nanyang Drive, Singapore 637553. 3 Laboratory of Photonics and Interfaces, Department of Chemistry and Chemical Engineering, Swiss Federal Institute of Technology, Station 6, CH-1015 Lausanne, Switzerland. 4 Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA 94720 5 National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 * Correspondence to:
[email protected],
[email protected] Keywords: (Hematite, Perovskite solar cell, Atomic layer deposition (ALD), water splitting, Tandem cell, EIS, TEM) Efficient water splitting driven by a single photoelectrode has remained elusive due to the challenge of driving this multi-electron process with high yield at low overpotentials, under visible light.[1] The oxygen evolution reaction (OER) is more challenging than the hydrogen evolution reaction (HER) due to the simultaneous participation of 4 electrons and 2 water molecules.[2] Several photo-anode materials have been investigated for photoelectrochemical OER reactions, such as BiVO4,[3] WO3[4] and Fe2O3.[5, 6] Hematite (α- Fe2O3) is attractive [7, 8] due to its favorable band gap (~2.1 eV), good stability, nontoxicity, abundance and economic viability.[9] Although theoretically estimated to achieve a solar-to-hydrogen efficiency of up to 15 %,[8] the reported efficiencies of α- Fe2O3 devices are far from this maximal value, mainly due to the short lifetime of photogenerated charge carriers (
