Strain modulation on graphene/ZnO nanowire mixed- dimensional van der Waals heterostructure for high- performance photosensor  

作　　者：Shuo Liu Qingliang Liao Zheng Zhang Xiankun Zhang Shengnan Lu Lixin Zhou Mengyu Hong Zhuo Kang Yue Zhang 

机构地区：[1]State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China [2]Beijing Municipal Key Laboratory for Advanced Energy Materials and Technologies, University of Science and Technology Beijing, Beijing 100083, China

出　　处：《Nano Research》2017年第10期3476-3485,共10页纳米研究（英文版）

基　　金：Acknowledgements This work was supported by the National Basic Research Program of China （No. 2013CB932602）, the National Key Research and Development Program of China （No. 2016YFA0202701）, the Program of Introducing Talents of Discipline to Universities （No. B14003）, National Natural Science Foundation of China （Nos. 51672026, 51602020, 51527802, and 51232001）, China Postdoctoral Science Foundation （Nos. 2015M580981 and 2016T90033）, Beijing Municipal Science ＆ Technology Commission, and the State Key Laboratory for Advanced Metals and Materials （No. 2016Z-06）, and the Fundamental Research Funds for the Central Universities （Nos. FRF-TP-15-075A1, FRF-BR-15-036A, and FRF-AS-15-002）.

摘　　要：The mixed-dimensional van der Waals （vdW） heterostructure is a promising building block for strained electronics and optoelectronics because it avoids the bond fracture and atomic reconstruction under strain. We propose a novel mixed-dimensional vdW heterostructure between two-dimensional graphene and a one-dimensional ZnO nanowire for high-performance photosensing. By utilizing the piezoelectric properties of ZnO, strain modulation was accomplished in the mixed-dimensional vdW heterostructure to optimize the device performance. By combining the ultrahigh electrons transfer speed in graphene and the extremely long life time of holes in ZnO, an outstanding responsivity of 1.87 ×10^5 A/W was achieved. Under a tensile strain of only 0.44% on the ZnO nanowire, the responsivity was enhanced by 26%. A competitive model was proposed, in which the performance enhancement is due to the efficient promotion of the injection of photogenerated electrons from the ZnO into the graphene caused by the strain-induced positive piezopotential. Our study provides a strain-engineering strategy for controlling the behavior of the photocarriers in the mixed-dimensional vdW heterostructure, which can be also applied to other similar systems in the future.The mixed-dimensional van der Waals （vdW） heterostructure is a promising building block for strained electronics and optoelectronics because it avoids the bond fracture and atomic reconstruction under strain. We propose a novel mixed-dimensional vdW heterostructure between two-dimensional graphene and a one-dimensional ZnO nanowire for high-performance photosensing. By utilizing the piezoelectric properties of ZnO, strain modulation was accomplished in the mixed-dimensional vdW heterostructure to optimize the device performance. By combining the ultrahigh electrons transfer speed in graphene and the extremely long life time of holes in ZnO, an outstanding responsivity of 1.87 ×10^5 A/W was achieved. Under a tensile strain of only 0.44% on the ZnO nanowire, the responsivity was enhanced by 26%. A competitive model was proposed, in which the performance enhancement is due to the efficient promotion of the injection of photogenerated electrons from the ZnO into the graphene caused by the strain-induced positive piezopotential. Our study provides a strain-engineering strategy for controlling the behavior of the photocarriers in the mixed-dimensional vdW heterostructure, which can be also applied to other similar systems in the future.

关 键 词：GRAPHENE ZnO nanowire vdW heterostructure strain modulation PHOTOSENSOR 

分 类 号：TN141[电子电信—物理电子学] TN818.06