Department of Electronic and Electrical Engineering, University College London , Torrington Place, London WC1E 7JE, United Kingdom.
Nano Lett. 2014;14(4):2013-8. doi: 10.1021/nl500170m. Epub 2014 Apr 1.
We present the wafer-scale fabrication of self-catalyzed p-n homojunction 1.7 eV GaAsP core-shell nanowire photocathodes grown on silicon substrates by molecular beam epitaxy with the incorporation of Pt nanoparticles as hydrogen evolution cocatalysts. Under AM 1.5G illumination, the GaAsP nanowire photocathode yielded a photocurrent density of 4.5 mA/cm(2) at 0 V versus a reversible hydrogen electrode and a solar-to-hydrogen conversion efficiency of 0.5%, which are much higher than the values previously reported for wafer-scale III-V nanowire photocathodes. In addition, GaAsP has been found to be more resistant to photocorrosion than InGaP. These results open up a new approach to develop efficient tandem photoelectrochemical devices via fabricating GaAsP nanowires on a silicon platform.
我们展示了在硅衬底上通过分子束外延生长的自催化 p-n 同质结 1.7eV GaAsP 核壳纳米线光阴极的晶圆级制造，其中掺入了 Pt 纳米颗粒作为析氢共催化剂。在 AM 1.5G 光照下，GaAsP 纳米线光阴极在 0V 相对于可逆氢电极的光电流密度为 4.5mA/cm(2)，太阳能到氢的转换效率为 0.5%，这远高于之前报道的晶圆级 III-V 纳米线光阴极的值。此外，已经发现 GaAsP 比 InGaP 更能抵抗光腐蚀。这些结果为通过在硅平台上制造 GaAsP 纳米线来开发高效的串联光电化学器件开辟了一条新途径。
