Efficient Water‐Splitting Device Based on a Bismuth Vanadate Photoanode and Thin‐Film Silicon Solar Cells. Issue 10 (19th August 2014)

• Record Type: Journal Article
• Authors: Han, Lihao; Abdi, Fatwa F.; van de Krol, Roel; Liu, Rui; Huang, Zhuangqun; Lewerenz, Hans‐Joachim; Dam, Bernard; Zeman, Miro; Smets, Arno H. M.
• Is Part Of: ChemSusChem. Volume 7:Issue 10(2014:Oct.)
• Page Start: 2832
• Page End: 2838
• Publication Date: 2014-08-19
• Subjects: Green chemistry -- Periodicals; Sustainable engineering -- Periodicals; Chemistry -- Periodicals; Chemical engineering -- Periodicals; 660
• DOI: 10.1002/cssc.201402456
• Languages: English
• ISSNs: 1864-5631

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>A hybrid photovoltaic/photoelectrochemical (PV/PEC) water‐splitting device with a benchmark solar‐to‐hydrogen conversion efficiency of 5.2 % under simulated air mass (AM) 1.5 illumination is reported. This cell consists of a gradient‐doped tungsten–bismuth vanadate (W:BiVO₄) photoanode and a thin‐film silicon solar cell. The improvement with respect to an earlier cell that also used gradient‐doped W:BiVO₄ has been achieved by simultaneously introducing a textured substrate to enhance light trapping in the BiVO₄ photoanode and further optimization of the W gradient doping profile in the photoanode. Various PV cells have been studied in combination with this BiVO₄ photoanode, such as an amorphous silicon (a‐Si:H) single junction, an a‐Si:H/a‐Si:H double junction, and an a‐Si:H/nanocrystalline silicon (nc‐Si:H) micromorph junction. The highest conversion efficiency, which is also the record efficiency for metal oxide based water‐splitting devices, is reached for a tandem system consisting of the optimized W:BiVO₄ photoanode and the micromorph (a‐Si:H/nc‐Si:H) cell. This record efficiency is attributed to the increased performance of the BiVO₄ photoanode, which is the limiting factor in this hybrid PEC/PV device, as well as better spectral matching between BiVO₄ and the nc‐Si:H cell.</p> </abstract>