The influence of electric fields on the chemisorption and catalytic properties of semiconductor catalysts

Studies of the influence of electric fields on the chemisorption and catalytic properties of semiconductor catalysts, carried out in order to test the principal postulates of the electronic theory of catalysis, are examined. It is shown that, because of the high density of the surface states, the possibility of the electronic control of the surfaces of polycrystalline catalysts by the field effect method is extremely limited. Possible ways of regulating the chemisorption and catalytic activities of solid catalysts with the aid of an external electric field are discussed: (1) the change in the concentration of polar molecules in strong inhomogeneous local fields near the surface; (2) the activation of surface compounds by "hot" electrons; (3) the modification of the defective structure when the concentration of cations in the surface layers of oxide catalysts is altered; (4) surface doping of film catalysts by alkali metals from the dielectric support during their electrolytic deposition. 130 references.