Surface Engineering of ZnO Nanostructures for Semiconductor‐Sensitized Solar Cells

Abstract

Semiconductor-sensitized solar cells (SSCs) are emerging as promising devices for achieving efficient and low-cost solar-energy conversion. The recent progress in the development of ZnO-nanostructure-based SSCs is reviewed here, and the key issues for their efficiency improvement, such as enhancing light harvesting and increasing carrier generation, separation, and collection, are highlighted from aspects of surface-engineering techniques. The impact of other factors such as electrolyte and counter electrodes on the photovoltaic performance is also addressed. The current challenges and perspectives for the further advance of ZnO-based SSCs are discussed.

Chemically Modified Metal Oxide Nanostructures Electrodes for Sensing and Energy Conversion

“…Note, ZnO (Eg ∼ 3.3 eV) only utilize the ultraviolet component (<5%) of the solar spectrum beside that it has also high recombination rate. 88 The same scenario is valid for the BiVO4. Although it is the most promising photocatalyst for water oxidation, poor photo-induced electron transportation, slow kinetics of oxygen evolution and a high charge recombination, are example of its limitations.…”

Pd nanocube decoration onto flexible nanofibrous mats of core–shell polymer–ZnO nanofibers for visible light photocatalysis

“…From this viewpoint, a direct semiconductor ZnO can be used which has wide band gap (3.37 eV) and strong exciton binding energy (60 meV), providing a great deal of interest for sunscreens, 18 antimicrobial agents, 19 solar energy conversion, 20 photocatalysis and environmental remediation. [21][22][23] In the electron/hole separation concept, UV light absorption causes electron/hole pairs and charge separation due to the large surface to volume ratios and the photon confinement effect, and exciton transfer gains a special importance for an improved photovoltaic effect. An effective way to improve the band absorption/emission features of ZnO is localized surface plasmon resonance (SPR) mediated enhancement.…”

Fabrication and photocatalysis of ZnO nanotubes on transparent conductive graphene-based flexible substrates

“…As a wide band-gap semiconductor oxide (E g =3.37 eV) with large excitation binding energy (60 meV), zinc oxide becomes one of the most important functional materials with unique properties of optical transparency, electric conductivity and piezo electricity [4][5][6][7][8][9][10]. However, the large band gap and the massive recombination of photogenerated charge carriers, especially in its nanosize, limit the overall photocatalytic efficiency.…”