Cd_1-xZn_xSe films with different zinc contents are deposited by an electron beam evaporation technique onto glass substrates for applications in solid-state photovoltaic devices. The structural, optical and photoelectrochemical (PEC) properties of Cd_1-xZn_xSe films are studied. The host material Cd_1-xZn_xSe is prepared by the physical vapor deposition method of electron beam evaporation technique (PVD: EBE) under a pressure of 1× 10^-5 mbar. The x-ray diffractogram indicates that these alloy films are polycrystalline in nature, hexagonal structure with strong preferential orientation of the crystallites along (002) direction. The optical properties shows that the band gap E_g varies from 2.08 to 2.84 eV as zinc content varies from 0.2 to 0.8. A PEC cell of the configuration n-Cd_1-xZn_xSe/Na₂S-S-NaOH is fabricated and the dynamic current-voltage characteristics in the dark atmosphere have been examined at room temperature. It has been found that both V_oc and I_sc decrease with the photoelectrode composition x. Efficiency η and fill factor (FF) also show similar variations. The material properties would be altered and excellently controlled by controlling the system composition x.

Thermoelectric performances of free-standing polythiophene (PT) and poly(3-methylthiophene) (PMeT) nanofilms with high tensile strength electrosynthesized from boron trifluoride diethyl etherate (BFEE) are systematically investigated. They display decent electric conductivity (47 and 73 S·cm^-1), high Seebeck coefficient (130 and 76 μV·K^-1) and low thermal conductivity (0.17 and 0.15 W·m^-1_·K^-1) at room temperature. Their figure of merit can reach 3.0×10^-2 at 250 K, higher than that of many other conducting polymers. The decrease of charge carrier concentration resulting from volatile and water-sensitive dopants from BFEE leads to the decrease of electrical conductivity but a substantial increase of the Seebeck coefficient, making their figure-of-merit values maintained at more than 10^-2 even after prolonged storage (two months). Moreover, free-standing PT and PMeT exhibit much better thermoelectric performances than those in pressed pellets due to the good arrangement of the polymer chains and preferably oriented structure in films. It therefore provides a way to improve the thermoelectric performances of conducting polymers by controlling regularity of the extended conjugated chain structure and/or the chain packing to achieve high charge mobility.

We present a simple method to synthesize Pb(OH)₂ nanorods by solution-phase reaction. Rod-like lead hydroxide precipitates are obtained by mixing lead nitrate with a concentration of about 0.01 M and potassium hydroxide with concentration of about 0.03 M in an aqueous solution. Sodium chloride as an additive is premixed with the lead nitrate aqueous solution. The presence of chloride ions in the precursor solution results in the rod-like morphology of lead hydroxide precipitates. The growth mechanism of the lead hydroxide nanorods is discussed.