A photoelectrochemical cell (PEC) was made by depositing platinum and polypyrrole film electrochemically in sequence on an n-Si substrate. The photoelectrochemical generation of thin polypyrrole films on the Si surface was performed with a tungsten-halogen lamp. The photovoltaic effect under illumination of 60mW/cm² tungsten-halogen light, and the rectification effect of the dark current as well as the long-term stability were investigated in n-Si | (Pt) | PPy | I^-(aq), I₃^-(aq) | Pt PEC with an iodine/triiodide electrolyte. The maximum short circuit current density was 2.9 mA/cm², and the maximum open circuit voltage was 320 mV. The calculated power conversion efficiency was 0.46% and the corresponding fill factor was 0.30. Comparing with the n-Si | I^-(aq), I₃^-(aq) | Pt or the n-Si | (Pt) | PPy | I^-(aq), I₃^-(aq) | Pt PEC, the n-Si | (Pt) | I^-(aq), I₃^-(aq) | Pt PEC showed better long-term stability as a solar cell.

무기반도체인 n-type Si위에 전기화학적인 방법으로 백금과 유기고분자인 p-type polypyrrole을 차례로 중합시킴으써 n-Si | Pt | Polypyrrole 이종접합을 형성하였다. 0.4 M KI + 0.02 M I₂ + 0.5 M KCI 수용액에서 n-Si | Pt | Polypyrrole 이종접합을 작업전극으로, 백금판을 보조전극으로 하여 photoelectrochemical cell(PEC)을 형성하고 이에 대한 정류 효과, 광전지효과, 그리고 시간에 따른 안정성을 조사하였다. 광전지효과 실험결과, short circuit전류 밀도는 2.9 mA/cm², open circuit전압은 320mV로 측정되었고 이로부터 fill factor는 0.30, 출력 효율은 0.46%로 계산되었다. 동일한 수용액에서 형성된 n-Si | I^-(aq), I₃^-(aq) | Pt 이나 n-Si | (Pt) | I^-(aq), | I₃^-(aq) | Pt PEC와 비교하였을 때 n-Si | (Pt) | PPy | I^-(aq), I₃^-(aq) | Pt PEC가 시간에 대해 상대적으로 더 안정된 결과를 보여주었다.

Keywords: photoelectrochemical cell; polypyrrole; photovoltaic effect; rectification effect