Light-Harvesting in n-ZnO/p-Silicon Heterojunctions

Abstract

Zinc oxide (ZnO) films were deposited onto Si to form n-ZnO/p-Si heterojunctions. Under the illumination of by both ultraviolet (UV) light and sunlight, obvious photovoltaic behavior was observed. It was found that the conversion efficiency of the heterojunctions increased significantly with increasing thickness of the ZnO film, and the mechanism for light-harvesting in the heterojunctions is discussed. The results suggest that ZnO films may be helpful to increasing the harvesting of UV photons, thus decreasing the thermalization loss of UV energy in Si-based solar cells.

Characterization of ZnO thin films grown on different p-Si substrate elaborated by solgel spin-coating method

“…The increasing of current under illumination is due to the electron-hole pair generation in the thin films and particularly at the depletion region of the p-Si [46]. In this same field, L. Li et al reported in the conversion efficiency of the heterojunctions which increases significantly under the illumination of both UV and sunlight, so that the efficiency of Si solar cells may be increased due to increased harvesting of UV light by the ZnO film [47]. This study is also confirmed by N. Baydogan et al [48].The Therefore, our results indicate that the porous silicon can be a good candidate to elaborate a ZnO thin films as an electrode for schottky diode as well as a potential substrate for photovoltaic's and optoelectronic applications.…”

Large-area and nanoscale n-ZnO/p-Si heterojunction photodetectors

“…Some studies on electrical and optoelectronic properties of ZnO nanostructure based heterojunctions have been reported in the recent past. 1,2,[17][18][19] Al-Henini et al 18 studied the electrical properties of the p-Si/n-ZnO nanowire heterojunction. Guo et al 2 have fabricated ZnO nanowire/n-Si heterojunction by using magnetron cosputtering technique and have demonstrated a strong responsivity of the diode for both visible and UV light.…”

“…Guo et al 2 have fabricated ZnO nanowire/n-Si heterojunction by using magnetron cosputtering technique and have demonstrated a strong responsivity of the diode for both visible and UV light. Very recently, Li et al 19 have fabricated n-ZnO/p-Si heterojunction by using a plasma-assisted molecular beam epitaxy technique and have also demonstrated a strong responsivity of the n-ZnO/p-Si heterojunction diode to both the visible and UV light. He et al 20 studied the electrical and photoelectrical performance of nanophotodiodes based on ZnO nanowire/p-Si hetrojunction.…”

Tunable Fabrication of CuO Nanoplates on ZnO Nanorods: Heterostructure Formation by Photodeposition for Enhanced Photocatalytic Activity

“…Moreover, the fast recombination of photogenerated electron–hole pairs in ZnO would lead to low quantum efficiency and diminish photocatalytic activity . Therefore, recently many efforts have been made in order to improve photocatalytic performance of ZnO, such as noble metal modification, elemental doping and coupling with narrow band gap semiconductors . Thereinto, combining ZnO with narrow band gap semiconductors (CuO, CdS, CdSe, etc.)…”