Effect of Surface States on the Electrochemical Behaviour of Single Crystal n‐ZnSe Photoelectrode

Abstract

Surface Photovoltage Spectroscopy (SPS) technique has been used to detect the surface states of ZnSe (110) surfaces. Aqueous electrolyte/ZnSe junction has been electrochemically investigated in dark and under illumination. The effect of surface states on the kinetics of charge transfer through the semiconductor-electrolyte (S/E) junction has been discussed. The low leakage and photocurrents measured by the application of D.C. bias were referred to the blocking nature of S/E interface, in which the localized and induced surface states play an important role. EinfluIl der Oberflachenzuetande auf das elektrochemische Verhalten yon n-ZnSe-EinkristallphotoelektrodenInhaltsiibersicht. Oberflachenfotospannungsspektroskopie wurde benutzt, um die Zustiinde auf ZnSe-(llO)-Oberfl&chen aufzuweiaen. f i r Kontakt eines waDrigen Elektrolyten und ZnSe mrd e im Dunkeln und unter Beleuchtung elektrochemisch untersucht. Der Effekt der Oberfl&chenzustinde auf die Kinetik der Ladungstrager beim Durchgang durch die Flache zwischen Halbleiter und Elektrolyt wird diskutiert. Die bei angelegter Gleichspamung gemessenen, kleinen Leck-und Fotostrome werden auf die Halbleiter/Elektrolytgrenzschicht zuriickgef iihrt, in der lokaliaierte und induzierte Oberflachenzustlinde eine grol3e Rolle spielen.

Properties of cation‐exchange membranes prepared by radiation grafting of acrylic acid onto tetrafluoroethylene–ethylene copolymers

“…The methods mentioned above have been described p r e v i o~s l y .~,~.~ The thermal and chemical resistances were determined by weight loss and the increase of the specific electric resistance, respectively, under various conditions by methods described in Refs. [14][15][16][17][18][19]. CEM were prepared also by the simultaneous method of grafting onto porous films with pore size from 0.5 to 2.0 pm under the following conditions: AAc concn, 40 wt %; Mohr's salt, 1.5 wt 5%; temp, 298 K; dose, 9 kGy, obtained by repeated irradiation, 3 periods, 5 h each, a t dose rate 0.6 kGy/h, for each day.…”