基于转移矩阵法的n-Si/n-Fe_2O_3光催化性能研究  

Study on the Photocatalytic Performance of n-Si/n-Fe_2O_3 Based on Transfer Matrix Method

作　　者：陈磊[1] 冯德强[1] 刘孟寅[1] 王卫超[1] 

机构地区：[1]南开大学电子信息与光学工程学院,天津300350

出　　处：《人工晶体学报》2016年第12期2758-2764,共7页Journal of Synthetic Crystals

基　　金：国家自然科学基金(21573117);天津市自然科学基金(13JCYBJC41100)

摘　　要：对平衡态及光照下非平衡态的n-Si/n-Fe2O3/electrolyte的能带结构进行了分析,同时结合转移矩阵法定量地计算Si中不同能量的电子/空穴穿过n-Si/n-Fe2O3势垒并满足水氧化还原电势要求的透射系数,从而得出光照与Fe2O3厚度对Si中电子/空穴透射能量的影响。结果表明：Fe2O3层厚度（1-10 nm）与光电压的增大,均可以使Si中电子满足水还原反应电势要求所需的最小能量减小,同时使Si中空穴满足水氧化反应电势要求所需的最小能量增大。通过选择合适的Fe2O3厚度（-7 nm）,可以使Si中的光生电子和光生空穴同时以较小的能量传输到电解液中并满足水氧化和水还原反应的电势要求。The band structure of n-Si/n-Fe2O3/electrolyte under equilibrium state and non-equilibrium state （illumination） were analyzed. The transmission coefficients of the carriers in Si acrossing the n-Si/ n-Fe2O3 potential barriers and simultaneously satisfying the requirement of water redox potential were calculated by transfer matrix method, which show the influence of illumination and Fe2O3 thickness on transmission energy of electrons or holes in Si. The calculation results indicate that, with the increase of photovohage and Fe2O3 thickness （1-10 nm）, the least transmission energy for electrons （holes） in Si, which meets the potential requirement for water reduction （oxidation）, becomes lower （higher）. By choosing a moderate Fe2O3 thickness （ - 7 nm）, both electrons and holes in Si can transfer to electrolyte and satisfy the potential requirement of water redox reaction with relatively low energy.

关 键 词：光催化 转移矩阵法 透射系数 n-Si/n-Fe2O3异质结 水氧化还原反应 

分 类 号：O643[理学—物理化学]