Synthesis of NiGa2O4 Octahedron Nanocrystal with Exposed {111} Facets and Enhanced Efficiency of Photocatalytic Water Splitting
Synthesis of NiGa2O4 Octahedron Nanocrystal with Exposed {111} Facets and Enhanced Efficiency of Photocatalytic Water Splitting
复制标题
具有暴露{111}面的NiGa2O4八面体纳米晶的合成和提高光催化水分解效率
DOI：
10.1002/cplu.201402279
复制
发表时间：
2015
期刊：
影响因子：
3.4
通讯作者：
Fu, Wen-Fu
中科院分区：
文献类型：
--
作者：
Kang, Lei;Lin, Zhe-shuai;Chen, Yong;Fu, Wen-Fu
首次在不使用任何模板剂或有机表面活性剂的情况下，通过简单的水热路线合成了具有反应性pH依赖的{111}晶面的八面体NiGa 2 O 4纳米晶体。八面体NiGa 2 O 4的{111}晶面显示出明显增强的光催化分解水产生氢和氧的能力和良好的光催化稳定性。密度泛函计算表明，混合统计占据的Ga/Ni（四配位和六配位Ga/Ni）最有可能暴露在NiGa 2 O 4的（111）表面，这非常有利于提高其光催化活性;光电化学性质表明，NiGa 2 O 4八面体比[100]生长方向的NiGa 2 O 4纳米棒具有更好的光电流。瞬态光电流衰减扫描结果表明，NiGa 2 O 4八面体暴露的{111}面电极表现出4 s的瞬态衰减时间，而对于具有[100]生长方向的NiGa 2 O 4纳米棒电极，该时间仅为2 s。 这种较长的瞬态衰减时间表明，电荷载流子复合率较低的NiGa 2 O 4八面体电极，这将有助于提高光催化活性。本研究还表明，设计具有适当形貌和表面结构的纳米结构是提高光激发电荷转移寿命和开发高活性半导体光催化剂的可行途径。
For the first time, octahedral NiGa2O4 nanocrystals having reactive pH-dependent {111} facets are synthesized through a facile hydrothermal route without using any template or organic surfactant. The {111} facets of octahedral NiGa2O4 display clearly enhanced photocatalytic generation of hydrogen and oxygen from water splitting and good photocatalytic stability. Density functional calculations suggest that mixed statistically occupied Ga/Ni (fourfold- and sixfold-coordinated Ga/Ni) are most likely to be exposed at the (111) surface of NiGa2O4, which is very favorable for enhancing the photocatalytic activities, and the photoelectrochemical properties show that the NiGa2O4 octahedron displays a better photocurrent than NiGa2O4 nanorods with the [100] growth direction. The transient photocurrent decay scan results demonstrate that the NiGa2O4 octahedron exposed {111} facet electrode exhibits a transient decay time of 4 s, whereas this time is only 2 s for NiGa2O4 nanorod electrodes with the [100] growth direction. This longer transient decay time indicates that the charge-carrier recombination rate is lower in the NiGa2O4 octahedron electrode, which will contribute to the enhancement of the photocatalytic activity. The present study also demonstrates that designing nanostructures with the appropriate morphology and surface structures is a feasible approach for enhancing the photoexcited charge-transfer lifetime and developing highly active semiconductor photocatalysts.
登录
查看更多内容
影响因子：
29.4
作者：
Minde Sun;S. Xiong;Xinglong Wu;Chengyu He;Ting-hui Li;P. K. Chu
通讯作者：
Minde Sun;S. Xiong;Xinglong Wu;Chengyu He;Ting-hui Li;P. K. Chu
影响因子：
3.3
作者：
P. Hotsenpiller;J. Bolt;W. Farneth;J. B. Lowekamp;G. Rohrer
通讯作者：
P. Hotsenpiller;J. Bolt;W. Farneth;J. B. Lowekamp;G. Rohrer
影响因子：
3.3
作者：
Hara, M;Komoda, M;Domen, K
通讯作者：
Domen, K
影响因子：
5.3
作者：
Xiaoxiang Xu;A. Azad;J. Irvine
通讯作者：
Xiaoxiang Xu;A. Azad;J. Irvine
影响因子：
3.7
作者：
Bell, Nicholas J.;Ng, Yun Hau;Amal, Rose
通讯作者：
Amal, Rose