At present, the routes for synthesis selleck products of CZTS nanocrystalline

materials can be subsumed under two broad categories: the hot-injection method [12, 21–23] and the LEE011 nmr solvothermal process [13, 18, 24–26]. Although the hot-injection method can be used to synthesize CZTS nanocrystals with narrow size distribution, this method suffers from several shortcomings such as the need of expensive raw materials with high levels of toxicity, complicated processes, and high reaction temperatures (above 250°C). In contrast with the hot-injection method, the solvothermal process, which usually produces hierarchical CZTS particles by one-pot reaction, possesses the advantages of simple process and relative cheap raw materials. Furthermore, it has been found that hierarchical particles can provide a large surface area along with the functions of generating light scattering and favoring electron transport, as compared with nanocrystals [13]. Up to now, anhydrous ethylenediamine [24, 26], the mixture of ethylenediamine and water [27–29], ethylene glycol [13, 18], triethylene glycol [18], and dimethyl formamide (DMF) [30] have been used as a solvent for the solvothermal method, respectively. In contrast with those organic solvents, water is much cheaper and more environment-friendly. Undoubtedly, if water is used to replace AZD1080 price these organic solvents, a hydrothermal route will be developed, which

is more desirable for the environment-friendly and low-cost synthesis of CZTS nanocrystalline materials. However, few investigations on synthesis of CZTS nanocrystalline of materials by the hydrothermal method have been reported, except the hydrothermal reactions with Na2S [31] or thiourea [32] as the sulfur source. Note that selecting a suitable sulfur source is important for exploring a green hydrothermal process for preparing CZTS nanocrystalline materials. It has been reported that H2S is usually generated as a toxic and corrosive

intermediate product from the reaction systems containing sulfur, Na2S, or thiourea as the sulfur source [33]. Different from those sulfur sources, l-cysteine has been used to prepare metal sulfide nanomaterials without the generation of H2S as a by-product [30]. Thus, in the current work, by the aid of ethylenediaminetetraacetic acid (EDTA) as a complexing agent, a low-cost and nontoxic hydrothermal route for synthesis of CZTS has been developed by using water as the solvent and l-cysteine as the sulfur source. The effects of the amount of EDTA, the mole ratio of the three metal ions, and the hydrothermal temperature and time on the phase composition of the obtained samples have been systematically investigated. The phase composition of the obtained CZTS sample has been further confirmed by Raman spectrometry. The microstructure and morphology of the pure CZTS sample have been characterized, and its optical absorption property has been examined.