Quaternary CuIn(S_1−xSe_x)₂ Nanocrystals: Facile Heating-Up Synthesis, Band Gap Tuning, and Gram-Scale Production

Abstract

Tetragonal chalcopyrite CuIn-(S1−x Se x )2 (0 ≤ x ≤ 1) nanocrystals were synthesized by reacting a mixture of CuCl, InCl3, S, and Se in the presence of oleylamine at 265 °C. The S/Se composition ratio in the CuIn(S1−x Se x )2 could be tuned across the entire composition range of x from 0 to 1 by modulating the S/Se reactant mole ratio. The tetragonal lattice constants, that is, a and c, increase linearly with the increase of Se content, following Vegard’s law. The band gap energies of CuIn(S1−x Se x )2 nanocrystals could be tuned in the range between 0.98 and 1.46 eV and change nonlinearly with respect to x, deriving a bowing parameter of 0.17 eV. In addition, the method developed in this study was scalable to achieve gram-scale production of stoichiometry-controlled CuIn(S1−x Se x )2 and CuIn1−x Ga x Se2 nanocrystals.

Electrochemical impedance analysis of spray deposited CZTS thin film: Effect of Se introduction

“…The peaks of S 2p appeared at the binding energies of 161.5 eV (S p3/2) and 163.2 eV (S p1/2) are consistent with the binding energy range of 160e164 eV of S in metal sulfides [15]. The Se 3p core level peak assigned to Se 3p1/2 located at 168.7 eV is in good accordance with values reported previously [16]. The peaks shown in Fig.…”

Effect of the stacked structure on performance in CZTSSe thin film solar cells

“…These characteristics are similar to those of CuIn(S 1−x ,Se x ), with notable peak broadening and a slight shift in the position of peaks at 332 cm −1 and 196 cm −1 [15]. It was previously reported that the Raman peaks for CZTSe are located at 192-197 and 231-235 cm −1 , whereas those for CZTS are located at 307-315 and 332-338 cm −1 , respectively.…”

Crystallite formation mechanism of CuIn(Se,S)2 synthesized using solvothermal method

“…[11] So far the thermal decomposition method (rapid hot-injection and heating-up methods) has been the most successful and widely used in CIS and CISS nanocrystal synthesis. [12][13][14] However, this synthesis is difficult to scale up because the reagents used are toxic and expensive and the processing process is complicated. CISS and CIS nanocrystals have also been reported successfully synthesized using hydrothermal [15,16] and solvothermal [17][18][19][20] methods.…”