Search

Cd4Cl3(OH)5 is a good precursor compound that can be easily converted into Cd(OH)2 or functional compounds CdS and CdSe. Novel 3D nanostructured Cd4Cl3(OH)5 nanoflower arrays were controllably synthesized through a simple low temperature hydrothermal process. The morphology was characterized by scanning electron microscopy, x-ray diffraction (XRD), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). The cadmium precursor, solution concentration, solvent, reaction temperature and reaction time are of great importance on the flower-like structure. The formation mechanism of the flower-like structure is also discussed. The Cd4Cl3(OH)5 nanoflowers as template compounds were further transformed into Cd(OH)2 and CdS nanoflowers by an anion-exchange reaction.

A series of ternary tetrapodal nanocrystals of CdSe(x)Te(1-x) with x = 0 (CdTe), 0.23, 0.53, 0.78, 1 (CdSe) were synthesized and used to fabricate hybrid nanocrystal/polymer solar cells. Herein, the nanocrystals acted as electron acceptors, and poly(2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) was used as an electron donor. It was found that the open circuit voltage (V(oc)), short-circuit current (J(sc)) and power conversion efficiency (η) of the devices all increased with increasing Se content in the CdSe(x)Te(1-x) nanocrystals under identical experimental conditions. The solar cell based on the blend of tetrapodal CdSe nanocrystals and MEH-PPV (9:1 w/w) showed the highest power conversion efficiency of 1.13% under AM 1.5, 80 mW cm(-2), and the maximum incident photon to converted current efficiency (IPCE) of the device reached 47% at 510 nm. The influence of nanocrystal composition on the photovoltaic properties of the hybrid solar cells was explained by the difference of the band level positions between MEH-PPV and the nanocrystals.

A facile route for synthesizing CuInSe2 nanocrystals was developed using an alkanethiol as ligand and noncoordinating octadecene as solvent. The CuInSe2 nanoparticles and nanoplates were obtained, depending on the reaction temperature and time. When the reaction temperature was set at 180 °C and reaction for an hour, CuInSe2 nanoparticles with an average size of 6.2 nm were produced. As the reaction time was prolonged to 3 h, nanoplates appeared inside the nanoparticles. When the reaction temperature was elevated to 210 °C and reaction for 3 h, triangular or hexagonal CuInSe2 nanoplates with sharp edges were synthesized. It was proposed that the Ostwald ripening induced the morphology evolution of the CuInSe2 nanoparticles into nanoplates at the higher temperature. The nanoparticles and nanoplates were characterized by transmission electron microscopy (TEM), selected area electron diffraction (SAED), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS). The UV–vis absorption spectra of the CuInSe2 nanoparticles were significantly blue-shifted in comparison with the bulk material due to the quantum confinement.