Arrays of ZnO/Zn(x)Cd(1-x)Se (0 ≤ x ≤ 1) core/shell nanocables with shells of tunable compositions have been synthesized on fluorine-doped tin oxide glass substrates via a simple ion-exchange approach. Through the effects of stoichiometry and type II heterojunction, optical absorptions of the nanocable arrays can be controllably tuned to cover almost the entire visible spectrum. Lattice parameters and band gaps of the ternary Zn(x)Cd(1-x)Se shells were found to have respectively linear and quadratic relationships with the Zn content (x). These ZnO/Zn(x)Cd(1-x)Se nanocable arrays are further demonstrated to be promising photoelectrodes for photoelectrochemical solar cells, giving a maximum power conversion efficiency up to 4.74%.

Porous anatase TiO2 spheres with sizes ranging from 150 to 250 nm were synthesized by a rapid microwave treatment of spherical titanium glycolate precursors preformed via an ethylene glycol-mediated sol–gel process. The effects of various experimental conditions on the formation of titanium glycolate precursors and final TiO2 spheres were investigated. A dye-sensitized solar cell (DSSC) assembled with the as-synthesized porous TiO2 spheres as photoanodes exhibits a 5% energy conversion efficiency, which is almost 40% higher than that made of the standard commercial Degussa P25 TiO2 nanopowders.

Bundles of homogeneously alloyed Cu2−x(SySe1−y) nanowires with various compositions (0 ≤ y ≤ 1) are controllably prepared via a simple water‐evaporation method under mild conditions. It is found that the nanowire bundles have similar copper contents (0.37 ≤ x ≤ 0.44) and morphologies, and the same face centered cubic (fcc) crystal structure and growth orientation of [110] over the entire composition range of y. To the best of the authors' knowledge, this is the first report on cubic phased ternary Cu2−x(SySe1−y) compounds. It is found that lattice parameter of the Cu2−x(SySe1−y) compound changes linearly with the S content. It is also shown that the direct and the indirect bandgaps of the nanowires vary quadratically with the S content and have bowing parameters of 0.20 and 0.21 eV respectively. Energy‐gap‐tuning via compositional change is achieved for both the direct (1.48−1.87 eV) and the indirect (0.50−0.90 eV) bandgaps. The trends of lattice parameter and bandgap variations are consistent with those described by Végard's Law.

Vertically aligned single crystalline ZnO nanorod arrays, approximately 3 μm in length and 50-450 nm in diameter are grown by a simple solution approach on a Zn foil substrate. CdS and CdSe colloidal quantum dots are assembled onto ZnO nanorods array using water-soluble nanocrystals capped as-synthesized with a short-chain bifuncional linker thioglycolic acid. The solar cells co-sensitized with both CdS and CdSe quantum dots demonstrate superior efficiency compared with the cells using only one type of quantum dots. A thin Al2O3 layer deposited prior to quantum dot anchoring successfully acts as a barrier inhibiting electron recombination at the Zn/ZnO/electrolyte interface, resulting in power conversion efficiency of approximately 1% with an improved fill factor of 0.55. The in situ growth of ZnO nanorod arrays in a solution containing CdSe quantum dots provides better contact between two materials resulting in enhanced open circuit voltage.

We report the mild hydrothermal synthesis of single-crystalline rutile TiO2 nanorod arrays (NRAs). The method reported here shows great versatility and can be used to grow TiO2 NRAs on a large diversity of substrates including Si, Si/SiO2, sapphire, Si pillars, and fluorine doped tin oxide (FTO)-covered glass. The average diameter and length of the nanorods prepared at typical conditions are ∼60 nm and 400 nm, respectively. Dye-sensitized solar cells assembled with the TiO2 NRAs grown on the FTO-covered glass as photoanode were prepared with a photoconversion efficiency of ∼1.10%.