利用光电流 ,光热信息和热电流方法研究了热对Ag在 1mol/LNaOH溶液中表面阳极膜光电流的影响 .所用光源为 4 88nm和 5 32nm的激光 .结果表明Ag2 O层具有半导体光电流特性 ,在Ag ,Ag2 O和AgO的转变过程中 ,光照下电极表面的温升不同 .对照循环伏安曲线 ,及光电流和热电流曲线 ,可以证明在电位朝负方向扫描过程中于 0 .37V出现的阳极光电流峰和 0 .1V出现的阴极光电流峰主要是由光照下温度升高引起的热电流所造成的 .光电流和热电流随着光强度的增强而线性增强
The influence of heat on the photocurrent of Ag electrode in alkaline solution was investigated by measuring photocurrent, photothermal signal and thermal current under the irraiation of laser beams with the wavelengths of 488 nm and 532 nm. It was found the photocurrent at the Ag 2O film was influenced by the temperature change at the electrode surface under the irradiation of light. During the electrochemical transfer between Ag, Ag 2O and AgO in the anodic film, the surface temperature changed obviously due to the different absorptance of the surface substances. It was suggested by comparing the voltammograms, photocurrent curves and thermal current curves that the anodic photocurrent peak at 0.37 V and the cathodic photocurrent peak at 0.10 V on the photocurrent cycle curves can be attributed to the temperature rise under the irradiation of light. the photocurrent and the thermal current increased proportionately with the increase of light intensity.
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