Photoelectrochemical Behavior of n-Type GaAs(100) Electrodes Coated by a Single Layer of Graphene
Photoelectrochemical Behavior of n-Type GaAs(100) Electrodes Coated by a Single Layer of Graphene
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DOI：
10.1021/acs.jpcc.6b00232
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发表时间：
2016-03
影响因子：
3.7
通讯作者：
Fan Yang;A. Nielander;R. Grimm;N. Lewis
中科院分区：
文献类型：
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作者：
Fan Yang;A. Nielander;R. Grimm;N. Lewis
将单层石墨烯涂层的n型GaAs（100）电极的光电化学行为与裸露的新蚀刻的n型GaAs（100）电极的光电化学行为进行了比较，这两种电极分别是与含有K3[Fe(CN)6]/K4[Fe(CN)6]的水溶液接触的电极，以及与含有一系列单电子氧化还原偶的非水溶液接触的电极，这些非水溶液选择了能斯特溶液电位的范围大于1 V。在模拟的1太阳光照下，石墨烯涂层电极在非水电解质（H2O浓度0.1%,v/v）中连续工作长达8小时，产生了20 mA cm-2的短路光电流密度，而在相同条件下，未保护的n-GaAs电极在~ 400 s内光电流密度迅速衰减。虽然单层石墨烯增强了n-GaAs光阳极在非水电解质中的稳定性，但石墨烯并不能完全保护与Fe(CN)63 - /4 - (aq)接触的光阳极。
The photoelectrochemical behavior of n-type GaAs(100) electrodes coated with a single layer of graphene was compared with the behavior of bare, freshly etched n-type GaAs(100) electrodes, both for electrodes in contact with an aqueous solution containing K3[Fe(CN)6]/K4[Fe(CN)6] and for electrodes in contact with nonaqueous solutions containing a series of one-electron redox couples selected such that the Nernstian solution potentials spanned a range greater than 1 V. Under simulated 1 Sun illumination, the graphene-coated electrodes produced a short-circuit photocurrent density of 20 mA cm–2 for up to 8 h of continuous operation in nonaqueous electrolytes (H2O concentration 0.1%, v/v), while, under the same conditions, the unprotected n-GaAs electrodes showed a rapid decay of the photocurrent density within ∼400 s. Although the graphene monolayers enhanced the stability of n-GaAs photoanodes in nonaqueous electrolytes, the graphene did not fully protect photoanodes operated in contact with Fe(CN)63–/4–(aq...