Some Experiments on the Photosensitization Mechanism of Semiconductors by Dyes^1a

Photoinduced interaction between xanthene dyes and colloidal CdS nanoparticles

“…The first successful experiment of this type was described by Putzeiko and Terenin [21,22]. The Domber effect of ZnO powder in visible light was sensitized by xanthene and cyanine dyes [23].…”

Photosensitization of Inorganic Solids*

“…Spectral sensitization by dyes is observed in a large number of photoconducting elements (Ge [3], Se [4], S[S]), halides (TlC1 [6,7], TIBr [8][9][10], T11 [6,10,111,NaCl [12], Hg12[9, 101, silver halides[lO, [13][14][15][16][17][18][19]), sulfides (CdS [20,21]) and oxides (ZnO [18,Pb0[10], Cu,0 [30], HgO [3,6], SnO2[31, CdO[31]). Because electronic charge carriers are generated, dye sensitization is a characteristic effect for various photoeffects.…”

“…(4) The sign of the charge carriers in sensitized photoeffects is in most cases the same as that of the intrinsic photoeffect of the semiconducting solid. For example, most carriers are electrons in sensitized n-type zinc oxide layers [7,38] and are holes in p-type thallium halides [38] or p-type gallium phosphide [39]. However there exists also the possibility of a dependence of the sign of the photocamer on the sensitizing dye.…”

A Review of the Spectral Sensitization of Silver Halides, Past and Present*

“…The experiments of Kuhn and his coworkers [46,471, using fatty-acid monolayers to space the spectral sensitizing dye away from the silver halide, have shown very convincingly that spectral sensitization of silver halide by energy transfer is possible by a dye spaced at a distance from the silver halide surface, but this finding still does not prove what the primary act of the dye is when it is absorbed directly on the silver halide grain. Experiments by Akimov and Terenin [48,49] also strongly support the energy transfer mechanism of spectral sensitization. They claimed that it was possible to make silver iodide so pure that it was not capable of being spectrally sensitized because no energy transfer acceptors were present, but exposing the same silver iodide introduced energy transfer acceptors.…”