• 한국세라믹학회지
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• 제32권11호
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• pp.1262-1268
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• 1995

Photoelectrochemical properties of p-GaAs electrode have been investigated. I-V characteristic shows that the cathodic photocurrent is observed at -0.7 V vs. SCE. The photoresponse at near 870~880nm wavelength indicates that the photogenerated carriers contibuted to the observed current. The maximum converson efficiency of 35% is obtained for a Xe lamp light source at 400nm. In C-V relation, capacitance peaks appeared at the frequencies of 100Hz and 300Hz due to the activation of the interfacial states which exist at the energy level corresponding to the one-third of the GaAs band gap. The difference of about 1.1V between flatband potential (Vfb) from the Mott-Schottky method and onset voltage from I-V curve is observed due to the trap of carriers at the interfacial states in the boundary between GaAs and electrolyte. In case of WO3 deposited p-GaAs electrode, higher positive onset current and photocurent density are obtained. This can be explained by the fact that carriers are generated by light penetrated into the WO3 thin flm as well as p-GaAs substrate and then move into the electrolyte effectively.

• 대한화학회지
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• 제37권12호
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• pp.1010-1018
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• 1993

티타늄 금속판을 양극산화하여 제조한 $TiO_2$ 박막을 전극으로 사용하여 1M NaOH 용액에서 광전기화학적 성질을 연구하였다. $TiO_2$ 전극들의 flatband potential은 대략 -0.8V 정도로 이들 값은 단결정 $TiO_2$에서 보다 0.2V만큼 양전위 방향으로 이동되어 나타났다. 순환 전압 전류법에 의한 산소의 환원전위는 SCE에 대해 -0.95V 근처에서 나타났으며, 반응은 전체적으로 비가역적으로 진행되었다. 또한 전극의 광전류는 단결정 $TiO_2$에서 보다 더 단파장에서 나타났으며 전류밀도는 감소되었다.