Kesterite Cu ₂ ZnSnS ₄ thin films synthesized utilizing electrodeposition: Influence of metal doping on the properties

Abstract

Summary In the present study, kesterite films were synthesized by sulfurization of co‐electrodeposited Cu2ZnSnS4 (CZTS) precursor, focusing on the effect of different metals (Li, Na, Sb, and Cr) on the CZTS thin films' properties. The structural, morphological, electrical and optical properties of the films were investigated. We demonstrated the deposition of four different metals using spin‐coating on co‐electrodeposited thin films. X‐ray diffraction (XRD) confirmed the kieserite phase with major intense peaks corresponding to the (112), (200), (312) and (332) planes with improvement in crystallinity after doping. Raman spectroscopy indicated the presence of a pure kesterite phase with a minor amount of impurities in the Na‐doped CZTS thin film. FE‐SEM analyses showed smooth, compact, and uniform surface morphology with fewer holes and cracks and well‐defined boundaries between the submicron particles and adherent layer cross section. An energy gap absorption edge ranging from 1.56 eV to 1.71 eV was calculated from the absorption measurements, while improvements in the energy gab were observed depending on the doping metal. The absorption coefficient was higher than 104 cm−1 in the visible spectrum of light. The performance of the solar cell with a device configuration of Glass/Mo/CZTS/CdS/i‐ZnO/ZnO: Al/Ag under simulated AM 1.5 was reported. The presence of different dopants increased the average efficiency from 1.74% ± 0.4 to 3.47% ± 0.3. Upon Na doping, solar cell device demonstrated as high‐performance efficiency as 3.47%, featuring open‐circuit voltage Voc = 343 mV, short‐circuit current density Jsc =12.55 mA/cm2, and a fill factor FF = 69.1.

Passivation of Grain Boundaries and Defects in CZTSSe Solar Cells by In Situ Na Doping

“…It is speculated that the doped Na element acts as an acceptor defect (Na Zn ), thereby increasing the majority carrier concentration in the absorber. [30,44] The improvement of carrier concentration is also consistent with the increasing trend of device V oc . [45] Based on Equation ( 9) and ( 10), we can obtain the carrier recombination coefficients in each region respectively.…”

Progress and Prospects with Cationic and Anionic Doping of Solution-Processed Kesterite Solar Absorbers: A Mini-Review

“…The Sb-CZTS solar cell device reported a 2.73% efficiency. 80 Numerical simulations with Cu 2 ZnFeSnS 4 (CZFTS)-based solar cells showed promising results with an efficiency of up to 20.35%. 81 It was observed that the incorporation of iron into CZTS causes a phase transition from kesterite to stannite.…”

“…After the Sb layer was coated, the morphology of the film was reported to be more smooth, compact, and uniform. The Sb-CZTS solar cell device reported a 2.73% efficiency …”

Study of optical and structural properties of CZTS thin films using copper capping layer and sulfurization to correct stoichiometry

“…However, as there are too many interdependent parameters which affect the deposition, parametric control is extremely difficult. Electrodeposition of CZT precursor followed by sulfurization at 580 °C for two hours was used to produce the CZTS thin films by Mkawi [15]. The author has explored effect of metallic doping by spin coating on the properties of the CZTS layer.…”

“…To name a few, optimizing the stacking order of precursor layers [25], sulfurization parameters like temperature, time [20], the gas flow rate during [26] the deposition process. The doping of the absorber layer to improve the efficiency as also explored [15]. Following are the main challenges in producing desired CZTS absorber layer.…”