不锈钢的光电响应测定

未经热或阳极氧化处理的不锈钢的光电响应极其微弱,测量很困难。至今,文献中尚未见有明确涵义的有关未经处理的不锈钢/溶液体系光电响应报道,仅等在这方面有过定性的研究,提及其为n型导电。本文采用了信号平均技术检测微弱的光响应,将多次信号叠加以提高其检测灵敏度。考虑到简化数据分析,用不含紫外光线的光源。在可见光谱段首次定量地测出了未经处理的1Cr18Ni9Ti不锈钢在溶液中的开路电极电势光响应(E_(ph,oc))波形、光电压波形峰-峰值(△V_(ph))～电极电势(E)的曲线,见图1和图2。

DETECTION OF THE PHOTOELECTRIC RESPONSES OF STAINLESS STEEL

Signal averaging technique was used to detect the weak photoelectric responses. at the interface of unpretreated 1Cr18Ni9Ti stainless steel electrode/solution over the visible range of radiation. Photoresponse of open-circuit electrode potential curve and potential dependence of the peak-peak photovoltages were obtained quantitatively for the first time. Similarity between the photoresponses of stainless steel and those of thicker Fe_2O_3 film suggests the existence of very thin n-type semiconductor film on the surface of stainless steel and the applicability of semiconductor physics to such thin film within proper limits. This technique may be developed into and improved in-situ method to characterize the structures and passive films at various metal/solution interfaces.