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Graphene/GaSe-Nanosheet Hybrid: Towards High Gain and Fast Photoresponse.

ABSTRACT: While high photoconductive gain has been recently achieved in graphene-based hybrid phototransistors using semiconductor two-dimensional transition/post-transition metal dichalcogenides or quantum dots sensitizers, obtaining fast photoresponse simutaneously remains a challenge that must be addressed for practical applications. In this paper we report a graphene/GaSe nanosheets hybrid photodetector, in which GaSe nanosheets provide a favorable geometric link to graphene conductive layer through van Der Waals force. After a vacuum annealing process, a high gain in exceeding 10(7) has been obtained simitaneously with a dynamic response time of around 10?ms for both light on and off. We attribute the high performance to the elimination of possible deep charge traps, most probably at the graphene/GaSe nanosheets interface. This result demonstrates high photoconductive gain and fast photoresponse can be achieved simultaneously and a clean interface is the key to the high performance of these hybrid devices.

SUBMITTER: Lu R

PROVIDER: S-EPMC4726015 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Graphene/GaSe-Nanosheet Hybrid: Towards High Gain and Fast Photoresponse.

Lu Rongtao R Liu Jianwei J Luo Hongfu H Chikan Viktor V Wu Judy Z JZ

Scientific reports 20160118

While high photoconductive gain has been recently achieved in graphene-based hybrid phototransistors using semiconductor two-dimensional transition/post-transition metal dichalcogenides or quantum dots sensitizers, obtaining fast photoresponse simutaneously remains a challenge that must be addressed for practical applications. In this paper we report a graphene/GaSe nanosheets hybrid photodetector, in which GaSe nanosheets provide a favorable geometric link to graphene conductive layer through v ...[more]

PMID: 26776942

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