SCIENCE CHINA Materials, Volume 61 , Issue 10 : 1297-1304(2018) https://doi.org/10.1007/s40843-018-9287-5

Improved water-splitting performances of CuW1−xMoxO4 photoanodes synthesizedby spray pyrolysis

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  • ReceivedJan 2, 2018
  • AcceptedApr 21, 2018
  • PublishedMay 25, 2018


CuW1−xMoxO4 solid solution of CuWO4 and CuMoO4, which is a copper-based multi-component oxide semiconductor, possesses much narrower band gap than CuWO4. In theory, it can absorb a larger part of the visible spectrum, widening the use of solar spectroscopy and obtaining a higher photo-to-chemical conversion efficiency. In this study, CuW1−xMoxO4 thin-film photoanodes on conducting glass were prepared using a simple and low-cost spray pyrolysis method. The resulting CuW1−xMoxO4 photoanodes perform higher photocurrent than CuWO4 photoanodes under AM 1.5G simulated sunlight illumination (100 mW cm−2) in 0.1 mol L−1 phosphate buffer at pH 7. Combined with IPCE and Mott-Schottky analysis, the enhancement of the photocurrent is due to the improvement of photon utilization and the increase of carrier concentration with the incorporation of Mo atoms. Moreover, with the optimal Mo/W atomic ratio, the photocurrent density increases obviously from 0.07 to 0.46 mA cm−2 at 1.23 VRHE bias. In addition, compared with particle-assembled thin-film photoanodes prepared by solid-phase reaction and drop-necking treatment, the photoanodes prepared by spray pyrolysis have obvious advantages in terms of reducing resistance and facilitating charge transport.

Funded by

the National Basic Research Program of China(973,Program,2013CB632404)

National Natural Science Foundation of China(21473090,51272102)

and a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.


This work was supported by the National Basic Research Program of China (973 Program, 2013CB632404), National Natural Science Foundation of China (21473090 and 51272102) and a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.

Interest statement

The authors declare that they have no conflict of interest.

Contributions statement

Li Z and Liang Q designed the work. Liang Q synthesized samples with assistance by Guo Y and Qian Q. Liang Q performed XRD, UV-vis, EIS and PEC measurement. Hu J performed the SEM measurement. Liang Q and Li Z wrote the article. All authors contributed to the general discussion and preparation of the manuscript.

Author information

Qing Liang received her bachelor degree from Nanjing University, China, in 2016. She is currently a master degree candidate at the College of Engineering and Applied Sciences, Nanjing University. Her research interest is photoanode materials for photoelectrochemical water splitting.

Zhaosheng Li was born in China in 1975 and received his PhD degree in condensed matter physics from the Institute of Solid State Physics, Chinese Academic of Sciences, China, in 2003. After a two-year postdoctoral fellowship at Nanjing University, he became a lecturer at this university. Since December 2011, he has been a full professor of Materials Science and Engineer at the College of Engineering and Applied Sciences, Nanjing University. His current research interests are photoelectrochemistry and photocatalysis.


Supplementary information

Experimental details and supporting data are available in the online version of the paper.


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  • Figure 1

    XRD patterns of CuW1−xMoxO4 samples. (a) View from 10° to 70°; (b) detail view from 29.5° to 33.5°. In the XRD patterns, the peaks from FTO substrate and Cu3Mo2O9 are denoted by symbols * and ◆, respectively.

  • Figure 2

    SEM images of as-prepared samples: (a) CuWO4, (b) CuW0.65Mo0.35O4 and (c) CuW0.5Mo0.5O4. HRTEM images of (d) CuWO4, (e) CuW0.65Mo0.35O4 and (f) CuW0.5Mo0.5O4. The inset images are the fast Fourier transform patterns of the corresponding images.

  • Figure 3

    UV-vis absorption spectra of CuW1−xMoxO4 thin-film samples.

  • Figure 4

    J-V curves of CuW1−xMoxO4 photoanodes measured in darkness and under AM 1.5G sunlight illumination (100 mW cm−2) in 0.1 mol L−1 phosphate buffer (pH 7). The short dash is dark response.

  • Figure 5

    (a) IPCE plots of CuW1−xMoxO4 photoanodes measured at 1.23 VRHE applied bias in 0.1 mol L−1 phosphate buffer (pH 7). (b) IPCE of CuW1−xMoxO4 photoanodes at +1.23 VRHE bias and the AM 1.5G solar spectrum (100 mW cm−2) are multiplied together to give the number of photons stored in the form of hydrogen (shaded area). (c) Mott-Schottky plots of CuW1−xMoxO4 photoanodes measured with the frequency of 1,000 Hz in darkness in 0.1 mol L−1 phosphate buffer (pH 7). (d) J-V curves of CuW1−xMoxO4 photoanodes measured under AM 1.5G sunlight illumination (100 mW cm−2) in 0.1 mol L−1 phosphate buffer (pH 7) containing hole scavenger of 0.1 mol L−1 H2O2.

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