Green Atmospheric Aqueous Solution Deposition for High Performance Cu₂ZnSn(S,Se)₄ Thin Film Solar Cells

Abstract

Environment‐friendly process, low production cost, and simple operation are regarded as key factors for scalable kesterite photovoltaic applications. Herein a green ammonium thioglycolate (TGAm)‐based aqueous solution route has been developed to deposit Cu2ZnSnS4 films. It is found that sinstering in ambient air is as good as in argon, making the production process more affordable and reproducible. TGAm is more active than other alkylthiols with longer alkyl chains and has a strong coordination capability toward metal ions, which is a key factor in the dissolution of a series of metal oxides. Meanwhile, TGAm is widely used in biopharmaceuticals and hairspray, demonstrating good biological compatibility. Moreover, a low level of Ag doping can be successfully incorporated into the host lattice of the CZTSSe to form a homogeneous (Cu1−x,Agx)2ZnSn(S,Se)4 (CAZTSSe) alloy material by this aqueous process. Benefiting from the effect of Ag doping, the initial power conversion efficiency is successfully enhanced from 5.86% (x = 0) to 7.38% (x = 2%).

Defect Engineering in Earth‐Abundant Cu2ZnSn(S,Se)4 Photovoltaic Materials via Ga3+‐Doping for over 12% Efficient Solar Cells

“…As previously reported, CZTSSe photovoltaic devices were fabricated with the traditional cell structure Glass/Mo/CZT(G)SSe/CdS/i‐ZnO/ITO/Ag/MgF 2 , and the active area of the targeted device is 0.21 cm 2 . [ 25,53–56 ] The CdS layer was prepared on the selenized film using chemical bath deposition (CBD) method, the solution temperature was 65 °C and the thick of CdS layer was ≈70 nm. Then, i‐ZnO (≈80 nm) layer and ITO (≈200 nm) layer was sequentially deposited on top of CdS by magnetron sputtering.…”

Deepening the Valance Band Edges of NiOx Contacts by Alkaline Earth Metal Doping for Efficient Perovskite Photovoltaics with High Open‐Circuit Voltage

“…However, the current doping strategy of NiO x HTLs is thus far insufficient for PSCs, compared with the organic HTLs, such as 2,2′,7,7′‐tetrakis‐( N , N ‐di‐4‐methoxyphenylamino)‐9,9′‐spirobifluorene (Spiro‐OMeTAD) and poly(triarylamine) (PTAA). Moreover, the general design rule for doping NiO x is still lacking …”

“…Moreover, the general design rule for doping NiO x is still lacking. [38][39][40] Herein, we systematically investigated the effect of alkali earth metal (Mg, Ca, Sr, and Ba) dopants on NiO x semiconductor materials, as inexpensive, stable, and solution-processed HTLs in PSCs. We found that the alkali earth metal heteroatoms in NiO x matrix can improve the hole conductivity and downshift the valance band.…”

Coordination engineering of Cu-Zn-Sn-S aqueous precursor for efficient kesterite solar cells

“…53 Owing to these potential advantages, TGA was once used for aqueous CZTSSe precursor preparation. [54][55][56] However, the resulting efficiency of 7.38% is still much lower than that of the hydrazine and other organic systems. This mainly arises because (1) the fundamental coordination chemistry of this aqueous system has not been clearly understood and (2) that how to precisely manipulate the complexes structure of TGA-metal to facilitate its application in CZTSSe solar cells has not been studied.…”