Hexagonal electrodeposited CdSe in new multi-layer hybrid organic–inorganic semiconductive systems with remarkable high photoconductivity

Production and identification of highly photoconductive CdSe-based hybrid organic-inorganic multi-layer materials

“…The counter electrode was a large platinum plated grid. The potential of the working electrode was monitored against an Hg/HgSO 4 constant at 85 ± 1 • C. The concentration of the additive (disodium oxalate) was set to 2 · 10 −3 mol/L. The bath pH value was adjusted to 2.2.…”

“…As presented in our previous works [4,5], hybrid semiconducting products may be developed by deposition of an appropriate thin organic film (specifically ferrocene, commercially obtained) placed between two CdSe thin films in a sandwich-like construction presenting remarkably improved photoresponding behavior [4]. On the other hand, CdSe semiconducting thin films electrodeposited in the presence of some selected organic additives, such as glutamates, oxalates, choline, etc., also exhibit remarkable photoconductive character.…”

“…CdSe, constituting the inorganic part of the hybrid system, is a well-known semiconductor, as referred in our previous works [2,[4][5][6][7] with a direct energy gap (1.7 eV). When electrodeposited, CdSe presents a well-developed cubic zinc-blende structure with a strong (111) preferred orientation [6,8], behaving as a metastable kinetically controlled phase, which can easily be transformed to the thermodynamically stable hexagonal one (wurtzite) by annealing [6].…”

“…However, hexagonal CdSe exhibits a better photoresponse in a photoelectrochemical cell (PEC) and higher resistance in photocorrosion partly due to its stronger bonding [6,7,9]. A pure hexagonal structure of CdSe has been obtained in the hybrid three-layer materials previously prepared [4]. The organic part, being an electron donor, had induced a significant change in the semiconductive behavior to the final hybrid as compared to the pure inorganic material [2].…”

Effect of thickness on structural, optical, electrical and morphological properties of nanocrystalline CdSe thin films for optoelectronic applications

“…The CdSe thin films may be deposited employing a number of techniques like thermal evaporation [3,10], chemical bath deposition [14,15], electro-deposition [16][17][18][19], hot wall deposition [20], spray pyrolysis [21], SILAR [22], etc. These techniques have their own merits and demerits.…”