Schottky enabled enhanced UV detection by graphene oxide composited transparent ZnO thin films
Schottky enabled enhanced UV detection by graphene oxide composited transparent ZnO thin films
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DOI：
10.1016/j.apsusc.2020.147149
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发表时间：
2020-07
影响因子：
6.7
通讯作者：
R. Gayen;R. Paul;S. Biswas
中科院分区：
文献类型：
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作者：
R. Gayen;R. Paul;S. Biswas
透明光电子器件最近引起了下一代电子技术的广泛研究关注。在这里，我们通过全溶液工艺制造了高透明（可见光下87％至90％）的氧化石墨烯（GO）和氧化锌（ZnO）复合薄膜。室温下的非线性电流-电压特性类似于 ZnO-GO 薄膜表面和银点之间肖特基势垒结的形成。在紫外线照射下（λ~375 nm，功率密度~1 mW/cm2），ZnO 和 ZnO-GO 25% 薄膜的理想因子从 7.82 增加到 8.72，但势垒高度从 0.66 eV 降低到 0.50 eV，这有利于推进光电技术。 ZnO-GO 25% 在低偏压 (+1 V) 下具有 5.3 A/W 的优异紫外光响应性以及低紫外响应 (15.8 秒) 和恢复时间 (36.6 秒) 证明了这一点。在-1 V 偏压下，光响应度达到 1.25 A/W。与其他关于全溶液处理的 ZnO-GO 复合材料的报道相比，这种独特的特性可归因于 GO 被还原，在 ZnO 基体中形成 rGO，从而在复合薄膜中形成导电通道，与 Ag 形成优异的肖特基势垒，通过 rGO 薄片和 ZnO 基体之间的界面区域的缺陷分布调节激子特性，以及促进通过结的电荷传输。
Transparent optoelectronics devices have recently drawn considerable research attentions for the next generation electronic technologies. Here, we fabricate highly transparent (87 to 90% under visible light) composite films of graphene oxide (GO) and zinc oxide (ZnO) by all-solution process. The non-linear current–voltage characteristics at room temperature resemble Schottky barrier junction formation between ZnO-GO film surface and Ag dot. Under UV irradiation (λ ~ 375 nm and power density ~1 mW/cm2) the ideality factor increases from 7.82 to 8.72 but the potential barrier height reduces from 0.66 to 0.50 eV in ZnO and ZnO-GO 25% films which are favorable for advancing optoelectronic technologies. This is demonstrated by excellent UV photoresponsivity of 5.3 A/W at low bias (+1 V) for ZnO-GO 25% along with low UV response (15.8 s) and recovery times (36.6 s). While at −1 V bias the photoresponsivity reaches to 1.25 A/W. Such distinct characteristics as compared to other reports on all-solution processed ZnO-GO composites could be attributed to the reduction of GO to form rGO within ZnO matrix to develop conducting channels in the composite films, the formation of excellent Schottky barriers with Ag, the modulation in excitonic characteristics by defect distributions at the interfacial regions among rGO flakes and ZnO matrix, and the facilitated charge transport through the junctions.