OPTICAL ELECTROCHEMISTRY .3. SPECTROSCOPY OF CONDUCTION-BAND ELECTRONS IN TRANSPARENT METAL-OXIDE SEMICONDUCTOR-FILMS - OPTICAL DETERMINATION OF THE FLAT-BAND POTENTIAL OF COLLOIDAL TITANIUM-DIOXIDE FILMS
OPTICAL ELECTROCHEMISTRY .3. SPECTROSCOPY OF CONDUCTION-BAND ELECTRONS IN TRANSPARENT METAL-OXIDE SEMICONDUCTOR-FILMS - OPTICAL DETERMINATION OF THE FLAT-BAND POTENTIAL OF COLLOIDAL TITANIUM-DIOXIDE FILMS
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DOI：
10.1021/j100193a062
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发表时间：
1992-07-09
影响因子：
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通讯作者：
GRATZEL, M
中科院分区：
文献类型：
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作者：
ROTHENBERGER, G;FITZMAURICE, D;GRATZEL, M
通过在导电玻璃载体上烧结直径为15 nm的锐钛矿型胶体粒子，制备了厚度为4-mU-m的透明纳米二氧化钛薄膜。测量了在-2.0~+1.0V(SCE)之间偏置的薄膜的可见光和近红外光谱，表明在负极化下在半导体/电解液界面形成了累积层。测量了导带电子在780 nm处的光学吸收，作为外加电势的函数，用来推导出纳米结构薄膜的平带电势和电子的消光系数。测量这种多孔电极中的平带电位的能力有助于优化界面电荷转移过程和设计高效的再生光电化学电池。
Transparent nanostructured TiO2 films (thickness 4-mu-m) were prepared by sintering 15-nm-diameter colloidal anatase particles on a conducting glass support. Visible and near-infrared spectra were measured for films biased at potentials between -2.0 and +1.0 V (SCE) and indicate the formation of an accumulation layer at the semiconductor/electrolyte interface under negative polarization. The optical absorbance of the conduction band electrons at 780 nm, measured as a function of the applied potential, has been used to derive the flatband potential of the nanostructured film and the extinction coefficient of the electrons. The ability to measure flatband potentials in such porous electrodes assists in the optimization of interfacial charge-transfer processes and the design of efficient regenerative photoelectrochemical cells.