Solution-Processed One-Dimensional ZnO@CdS Heterojunction toward Efficient Cu2ZnSnS4 Solar Cell with Inverted Structure

Abstract

Kesterite Cu2ZnSnS4 (CZTS) semiconductor has been demonstrated to be a promising alternative absorber in thin film solar cell in virtue of its earth-abundant, non-toxic element, suitable optical and electrical properties. Herein, a low-cost and non-toxic method that based on the thermal decomposition and reaction of metal-thiourea-oxygen sol-gel complexes to synthesize CZTS thin film was developed. The low-dimensional ZnO@CdS heterojunction nano-arrays coupling with the as-prepared CZTS thin film were employed to fabricate a novel solar cell with inverted structure. The vertically aligned nanowires (NWs) allow facilitating the charge carrier collection/separation/transfer with large interface areas. By optimizing the parameters including the annealing temperature of CZTS absorber, the thickness of CdS buffer layer and the morphology of ZnO NWs, an open-circuit voltage (VOC) as high as 589 mV was obtained by such solar cell with inverted structure. The all-solution-processed technic allows the realization of CZTS solar cell with extremely low cost.

Impact of molybdenum out diffusion and interface quality on the performance of sputter grown CZTS based solar cells

“…The chemical composition and structural properties of the CZTS layer depend on the deposition process and sulphurization temperature 17, 18 . Among several deposition methods 9–14, 19, 20 , sputter deposition technique provides precise control of film thickness over large area, in-situ crystal quality by tuning working pressure during deposition, and chemical composition of the deposited layer 21–23 . Furthermore, deposition of CZTS using a single-step sputtering from a quaternary Cu 2 ZnSnS 4 target offers many advantages, including the uniform composition of the thin film, smooth surface, simple process and high reproducibility 24 .…”

Activating ZnO nanorods photoanodes in visible light by CdS surface sensitiser

“…The CdS layer deposited by NCLD was not observed from XRD analysis. This might be due to the smaller amount of CdS nanocrystal deposition on the surface of ZnO NRs [19].…”

“…CdS buffer layer was coated on the surfaces of the prepared ZnO NRs using nanocrystal layer deposition (NCLD) technique [19, 21]. An aqueous precursor solution containing 20 mM CdSO 4 and 20 mM thioacetamide were mixed and sonicated for 10 min.…”

“…NRs: ZnO NRs were deposited on fluorinedoped tin oxide (FTO)-coated soda lime glass (SLG) substrate (Techinstro, sheet resistance 15Ω/□) using spin coating followed by electro chemical deposition technique. Spin coating was used at 1500 rpm for 30 s to deposit ZnO seed layer using the precursor solution which was prepared by adding 0.5 M Zn (CH 3 COO) 2 and 0.5 M di-ethanolamine in isopropanol [19]. The coated sample was dried on a preheated hot plate at 180°C for 10 min.…”

Solution-processed Cu2ZnSnS4 thin film with mixed solvent and its application in superstrate structure solar cells

“…The reported conversion efficiency of the superstrate structure was gradually increased from 0.84% to 3.63%. [12][13][14][15][16][17] The superstrate structure is benecial in supplying enough driving force to facilitate electron injection, 18 the CZTS absorber-TiO 2 conductor interface plays a crucial role in the device's efficiency, however, there is few study to discuss this issue.…”