Solution fabrication of large-area Si/TiO2 core/shell nanowire arrays modified by Au nanoparticles with high photoactivity for solar water splitting.
Large-area Si/TiO2 core/shell nanowire arrays were prepared for the first time by solution approach, followed by annealing in Ar (SiNWs/TiO2-Ar) and air (SiNWs/TiO2-air) atmosphere, respectively. Au nanoparticles were decorated onto the SiNWs/TiO2-Ar samples (SiNWs/TiO2@AuNPs-Ar) to further improve the photoactivity. XRD results showed that the TiO2 shells have an anatase crystalline structure. Photocurrent of solar water splitting was measured by a three electrode setup, in which the Si/TiO2 core/shell nanowire array served as the working electrode. It was found for the first time that Ar ambience annealing is more helpful improving the photocurrent density. The SiNWs/TiO2-Ar sample enhanced the photocurrent by 6.3 times compared to the SiNWs/TiO2-air sample. Furthermore, the SiNWs/TiO2@AuNPs-Ar arrays exhibited a photocurrent of 0.9 mA/cm2, 3.6 times as high as that of its counterpart without Au nanoparticles.
Functional Nanomaterials Laboratory and Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, China.
Li
L
Liu
Yang
Y
Cao
Junhui
J
He
Xiaopeng
X
Qi
Wensheng
W
Shi
Qiaowen
Q
Yang