A facile and low cost synthesis of earth abundant element Cu2ZnSnS4 (CZTS) nanocrystals: Effect of Cu concentrations

Abstract
Cu2ZnSnS4 (CZTS) nanocrystals (NCs) were synthesized by sulfurization of microwave assisted precursor powders without toxic chemicals. The effects of different Cu concentration from 0.01 to 0.025 M on the structural, morphological, compositional, chemical and optical properties of CZTS NCs were investigated. X-ray diffraction patterns, X-ray photoelectron spectroscopy and transmission electron microscopy results showed that the precursor powder contains several broad peaks that could not be assigned to CZTS, ZnS, Cu2-xS, Sn2S3 and Cu2SnS3. However, the sulfurized NCs showed both kesterite CZTS and Cu- and Sn-based secondary phases except for that formed at Cu concentration of 0.02 M. Inductively coupled plasma (ICP) results showed that the presence of Cu in the sulfurized CZTS NCs increased with increasing Cu concentration from 16.57 to 32.94 at.% while Zn and Sn in the sulfurized CZTS NCs decreased with increasing Cu concentration. UV–Vis spectroscopy results showed that the absorption coefficient of the sulfurized NCs was over 104 cm−1 in the visible region and band gap energy of the sulfurized CZTS NCs decreased from 1.65 to 1.28 eV with increasing Cu concentration.

Highlights
► Cu2ZnSnS4 (CZTS) nanocrystals (NCs) were prepared by sulfurization of microwave assisted precursor without toxic chemicals. ► Effect of Cu concentration on the properties of CZTS NCs was investigated using various analysis methods. ► The properties of CZTS NCs was strongly related to the Cu concentrations.



Seung Wook Shin (a), Jun Hee Han (a), Chan Yeong Park (b), Sae-Rok Kim (b), Yeon Chan Park (b), G.L. Agawane (b), A.V. Moholkar (c), Jae Ho Yun (d), Chae Hwan Jeong (e), Jeong Yong Lee (a), Jin Hyeok Kim (b)
a Department of Materials Science and Engineering, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, South Korea
b Photonics Technology Research Institute, Department of Materials Science and Engineering, Chonnam National University, 300 Yongbong-Dong, Buk-Gu, Gwangju 500-757, South Korea
c Electrochemical Mat. Lab, Department of Physics, Shivaji University, Kolhapur 416-004, India
d Photovoltaic Research Group, Korea Institute of Energy Research, 71-2 Jang-Dong, Yuseong-Gu, Daejeon 305-343, South Korea
e Solar City Center, Development of Advanced Components & Materials Korea Institute of Industrial Technology, Gwangju 500-480, South Korea



Journal of Alloys and Compounds
Volume 541, 15 November 2012, Pages 192–197


ScienceDirect.com - Journal of Alloys and Compounds - A facile and low cost synthesis of earth abundant element Cu2ZnSnS4 (CZTS) nanocrystals: Effect of Cu concentrations:

Martensitic transition of Mn-rich Pd–Mn–Sn alloy

Abstract
A new magnetic shape memory alloy Pd2Mn1.46Sn0.54 has been synthesized. It was found that in the austenite phase Pd2Mn1.46Sn0.54 crystallizes in the L21 structure. It was confirmed from the low temperature X-ray diffraction measurements that the martensite phase of Pd2Mn1.46Sn0.56 has an orthorhombic four-layered structure. The magnetization versus temperature curve of Pd2Mn1.46Sn0.54 is very similar to those of the Ni–Mn–Z (Z = In, Sn and Sb) magnetic shape memory alloys; the paramagnetic–ferromagnetic transition appears in the austenite phase with decreasing temperature. With further decrease of temperature, the magnetization and permeability decrease abruptly at the martensitic transition temperature. The martensite phase remains ferromagnetic at low temperatures.

Highlights
► This is the first report of clear evidence of the martensitic transition in Pd–Mn–Sn new material. ► Pd2Mn1.46Sn0.54 exhibits martensitic transition from ferromagnetic L21 phase to paramagnetic 4O phase. ► A smaller magnetic moment of Pd than that of Ni for other Ni-based shape memory alloys is suggested.



T. Kanomata (a, b), Y. Chieda (a), H. Okada (a), H. Nishihara (c), A. Kimura (d), M. Nagasako (b), R.Y. Umetsu (e), R. Kainuma (b), K.R.A. Ziebeck (f)
a Faculty of Engineering, Tohoku Gakuin University, Tagajo 985-8537, Japan
b Department of Materials Science, Graduate School of Engineering, Tohoku University, Sendai 980-8579, Japan
c Faculty of Science and Technology, Ryukoku University, Otsu 520-2194, Japan
d Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
e Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
f Department of Physics, Cavendish Laboratory, University of Cambridge, CB3 0HE, UK



Journal of Alloys and Compounds
Volume 541, 15 November 2012, Pages 392–395


ScienceDirect.com - Journal of Alloys and Compounds - Martensitic transition of Mn-rich Pd–Mn–Sn alloy:

'via Blog this'

Studies of CoSn grains in the carbon matrix structure of nanostructured tin–cobalt–carbon

Small angle neutron scattering (SANS) and transmission electron microscopy (TEM) have been used to qualitatively analyze the structure of Sn30Co30C40 alloys produced by vertical axis mechanical attriting to those produced by magnetron sputter deposition. From SANS and TEM, CoSn grains embedded in a carbon matrix structure were observed for all samples. The size of CoSn grains in the attrited samples was approximately 10 ± 3 nm by both TEM and SANS, while that of the sputtered samples was about 7 times smaller.

Highlights
► Sn–Co–C alloys as negative electrode for Li-ion batteries. ► Sn–Co–C alloys prepared by mechanical alloying and by sputtering. ► CoSn grains embedded in carbon matrix structure was observed from SANS and TEM. ► SANS quickly characterized Sn–Co–C alloys equivalently to TEM.


P.P. Ferguson (a), M.D. Fleischauerb (b), J.M. LaForge (c), A.D.W. Todd (d), P. Li (b), J.R. Dahna, (e),
a Dept. of Physics and Atmospheric Science, Dalhousie University, Halifax, NS, Canada B3H 3J5
b NRC, National Institute for Nanotechnology, Edmonton, AB, Canada T6G 2M9
c Dept. of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada T6G 2V4
d NRC Institute for National Measurements Standards, Ottawa, ON, Canada K1A 0R6
e Institute for Research in Materials, Dalhousie University, Halifax, NS, Canada B3H 3J5


Journal of Alloys and Compounds
Volume 541, 15 November 2012, Pages 168–172

http://www.sciencedirect.com/science/article/pii/S0925838812012339