Growth properties and electrochemical characterization of InGaN photoanodes with different In concentrations
Growth properties and electrochemical characterization of InGaN photoanodes with different In concentrations
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DOI：
10.1002/pssc.201300414
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发表时间：
2014-02
期刊：
影响因子：
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通讯作者：
M. Finken;A. Wille;Benjamin Reuters-;B. Holländer;M. Heuken;H. Kalisch;A. Vescan
中科院分区：
文献类型：
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作者：
M. Finken;A. Wille;Benjamin Reuters-;B. Holländer;M. Heuken;H. Kalisch;A. Vescan
利用半导体光电极通过光化学电解水产生氢气是一种很有前途的可再生能源。在这项工作中，InGaN层生长的金属有机气相外延（MOVPE）。通过在800 °C和720 °C之间改变生长温度来实现不同的In浓度。利用高分辨X射线衍射（HRXRD）、卢瑟福背散射（RBS）和原子力显微镜（AFM）对薄膜的性能进行了研究。在GaN/InGaN界面处的最大In浓度为11%。在较低的生长温度下朝向表面的进一步增加通过弛豫实现。这导致从2D到3D的生长模式的变化和晶体质量的总体下降。此外，两个Si掺杂的InGaN层生长的In含量为7%和25%，以研究其对光电阳极的性能的影响。通过计时电流法在三电极配置的光电阳极进行电化学检查。结果表明，在工作电极和参比电极之间的低电压EWE下，具有7% In的样品的光电流较高，而对于高于0.8V的电压，反之亦然。（© 2014 WILEY-VCH Verlag GmbH & Co. KGaA，魏因海姆）
The generation of hydrogen via the photochemical electrolysis of water by employing a semiconductor photoelectrode is a promising approach for a renewable energy source. In this work, InGaN layers grown by metal-organic vapour phase epitaxy (MOVPE). Different In concentrations were achieved by variation of the growth temperature between 800 °C and 720 °C. The properties of the layers were investigated by high-resolution X-ray diffraction (HRXRD), Rutherford backscattering spec-trometry (RBS) and atomic force microscopy (AFM). The maximum In concentration at the GaN/InGaN interface is 11%. A further increase towards the surface at lower growth temperatures is achieved by relaxation. This causes a change in the growth mode from 2D to 3D and an overall decrease of crystal quality. Additionally, two Si-doped InGaN layers were grown with In contents of 7% and 25% to investigate its influence on properties of a photoanode. The photoanodes were electrochemically examined via chronoamperometry in a three-electrode configuration. It is shown that at low voltages EWE between working electrode and reference electrode, the photocurrent of the sample with 7% In is higher, whereas for voltages above 0.8 V, it is vice versa. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)