Towards low-cost, environmentally friendly printed chalcopyrite and kesterite solar cells

Abstract

Solution-processed organic and inorganic semiconductors offer a promising path towards low-cost mass production of solar cells. Among the various material systems, solution processing of multicomponent inorganic semiconductors offers considerable promise due to their excellent electronic properties and superior photo-and thermal stability. This review surveys the recent developments of "all solutionprocessed" copper-indium (-gallium)-chalcogenide (CuInS 2 , CuInSe 2 and Cu(In, Ga)(Se, S) 2) chalcopyrites and copper-zinc-tin-chalcogenide (Cu 2 ZnSnS 4 and Cu 2 ZnSnSe 4 (CZTS(e))) kesterite solar cells. A brief overview further addresses some of the most critical material aspects and associated loss mechanisms in chalcopyrite and kesterite devices. Today's state-of-the-art performance as well as future challenges to achieve low-cost and environmentally friendly production is discussed. Broader context Photovoltaics as the only truly portable renewable-energy conversion technology available today demonstrate strong commercial growth and hold promise for signicant market opportunities. Among various solar cell technologies, thin-lm technologies are one of the cost-competitive solar technologies due to reduced material and fabrication costs. However, the production of thin lm solar cells typically relies on capex intense vacuum-based techniques, and/or hightemperature processes, both increasing manufacturing costs. Solution processing of multicomponent inorganic solar cells is considered as a promising alternative fabrication route to the conventional high cost vacuum techniques.

Molecular-ink route to 13.0% efficient low-bandgap CuIn(S,Se)2 and 14.7% efficient Cu(In,Ga)(S,Se)2 solar cells

“…Several solution approaches have been developed, but challenges such as low device efficiency, carbon contamination, and the necessity to use toxic and explosive reagents could not be addressed simultaneously. 9 The use of alcohol-based solvents and organic binder materials was seen to leave carbon-rich residual layers 10,11 while other non-vacuum routes necessitate highly reactive gases (i.e. H2, H2S, or H2Se) to reduce precursor layers [12][13][14] or toxic KCN etching to remove binary selenides.…”

A comprehensive study on the mechanism behind formation and depletion of Cu2ZnSnS4 (CZTS) phases

“…1,3,4 Additionally CZTS consists of earth abundant as well as non-toxic elements as compared to other semiconductors used in solar cells like CdSe/Te, PbS(e), CuInS 2 , CuIJIn,Ga)IJSe,S) 2 , CuInSe 2 etc. 5 Presently, solar cells using CZTSSe have reached efficiencies as high as 12.7% leading to promising future perspectives. 6 From a fundamental point of view, multicomponent particles are just one prominent example of materials with complex composition, i.e.…”

“…In the first instance, it allows the production of inks that can be used in costefficient (at best) roll-to-roll printing processes. 5,15 Moreover, the by-products or different structures often nucleate as single particles, distinct and well separated from the main product in the solution phase. Therefore, the by-products may be selectively separated after synthesis.…”

A review on applications of Cu2ZnSnS4 as alternative counter electrodes in dye-sensitized solar cells

“…9(a). 51 Inset of the same plot, a schematic of CZTS based DSSC system has also been given. The EIS study further elucidate about the catalytic activity of the different synthesized CZTS with Pt in the presence of I 3 -.…”

“…They are carbon, metal sulfide and oxide based, transition metal nitrides and carbides, polymers and carbon-polymer composites and other composites. [46][47][48][49][50][51][52][53][54][55] Remarkably, all the alternative CEs are established as a potential replacement to Pt in due course of its synthesis strategy, morphology-size tunable property, fabrication policy etc. The reported alternative CEs mainly concentrating on different synthesis processes which can lead to industrial scale manufacturing.…”