title: A nontoxic and low-cost hydrothermal route for synthesis of hierarchical Cu2ZnSnS4 particles.
abstract: We explore a facile and nontoxic hydrothermal route for synthesis of a Cu2ZnSnS4 nanocrystalline material by using l-cysteine as the sulfur source and ethylenediaminetetraacetic acid (EDTA) as the complexing agent. 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 product have been systematically investigated. The addition of EDTA and an excessive dose of ZnCl2 in the hydrothermal reaction system favor the generation of kesterite Cu2ZnSnS4. Pure kesterite Cu2ZnSnS4 has been synthesized at 180°C for 12 h from the reaction system containing 2 mmol of EDTA at 2:2:1 of Cu/Zn/Sn. It is confirmed by Raman spectroscopy that those binary and ternary phases are absent in the kesterite Cu2ZnSnS4 product. The kesterite Cu2ZnSnS4 material synthesized by the hydrothermal process consists of flower-like particles with 250 to 400 nm in size. It is revealed that the flower-like particles are assembled from single-crystal Cu2ZnSnS4 nanoflakes with ca. 20 nm in size. The band gap of the Cu2ZnSnS4 nanocrystalline material is estimated to be 1.55 eV. The films fabricated from the hierarchical Cu2ZnSnS4 particles exhibit fast photocurrent responses under intermittent visible-light irradiation, implying that they show potentials for use in solar cells and photocatalysis.
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering, and Materials Science, Soochow University, Suzhou 215123, China ; Suzhou Jufeng Electrical Insulation System Co. Ltd, Suzhou 215214, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Ministry of Education, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Ministry of Education, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
authors.forename: Zhengguo
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Ministry of Education, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Fang
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, College of Chemistry, Chemical Engineering, and Materials Science, Soochow University, Suzhou 215123, China.
authors.forename: Guozheng
authors.initials: G
authors.lastname: Liang
keywords: Cu2ZnSnS4; Hierarchical particles; Hydrothermal process; Nanocrystalline material; Photoelectrochemical property