Design and synthesis of ternary semiconductor Cu7.2(SexS1−x)4 nanocrystallites for efficient visible light photocatalysis
Design and synthesis of ternary semiconductor Cu7.2(SexS1−x)4 nanocrystallites for efficient visible light photocatalysis
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DOI：
10.1039/c0ce00524j
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发表时间：
2011-02
期刊：
影响因子：
3.1
通讯作者：
Yuan-hao Gao;Zhi Zheng;Feng-ling Yang;Fujuan Zhang;Pinjiang Li;W. Fa;Huimin Jia;Hongxiao Zhao
中科院分区：
文献类型：
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作者：
Yuan-hao Gao;Zhi Zheng;Feng-ling Yang;Fujuan Zhang;Pinjiang Li;W. Fa;Huimin Jia;Hongxiao Zhao
在温和的条件下合成了一系列新的三元半导体化合物Cu7.2(SexS1−x)4(0.2≤x≤0.8)纳米晶，在可见光照射下表现出良好的光催化活性。用粉末X射线衍射仪、透射电子显微镜、能谱和紫外-可见吸收光谱对Cu7.2(SexS1−x)4纳米晶进行了表征。从X射线数据中发现，不同样品的晶胞常数a与成分x呈线性关系：A(A)=5.5959+0.1586x。UV-Vis吸收光谱表明，可以通过调整组份x来调节表观带隙能量，从而更好地与整个太阳光谱相匹配。与研究最多的只对紫外光有响应的二氧化钛不同，Cu7.2(SexS1−x)4纳米晶在可见光下对罗丹明B的降解表现出更好的光催化活性。认为Cu7.2(SexS1−x)4纳米晶的光催化优势主要是由于化合物中Se/S组分的不均匀分布而产生的组成梯度，这可能导致Cu7.2(SexS1−x)4光催化剂中更有效的电荷分离/传输。
A new series of ternary semiconductor compounds, Cu7.2(SexS1−x)4 (0.2 ≤ x ≤ 0.8) nanocrystallites, that exhibited good photocatalytic activity under visible-light irradiation, were facilely synthesized under mild conditions. The Cu7.2(SexS1−x)4 nanocrystallites were characterized by powder X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy and UV-Vis absorption spectra. From X-ray data it is found that the cell constant a of different samples varies linearly with the composition x as: a (A) = 5.5959 + 0.1586x. UV-Vis absorption spectra indicate that the apparent band gap energies can be tuned by adjusting the composition x so as to better match to the whole solar spectrum. Unlike the most studied TiO2 that only responds to the UV-light irradiation, the present Cu7.2(SexS1−x)4 nanocrystallites exhibited much better photocatalytic activity under visible light on degradation of RhB. It is believed that the photocatalytic superiority of the Cu7.2(SexS1−x)4 nanocrystallites is mainly due to the compositional gradient arisen from uneven distribution of Se/S compositions in the compounds, which may induce a more efficient charge separation/transport in the Cu7.2(SexS1−x)4 photocatalysts.