Kesterite tech news
On October 23, 2026, researchers published a study in Advanced Functional Materials demonstrating a precursor doping source layer (PDSL) engineering strategy to resolve efficiency bottlenecks in pure--sulfide kesterite (${\text{Cu}}_2{\text{ZnSnS}}4$ or CZTS) solar cells. Pure--sulfide kesterites offer a non--toxic, earth--abundant alternative for thin--film photovoltaics and tandem cell applications, but commercialization has been hindered by severe copper--zinc (${\text{Cu}}{\text{Zn}}$) antisite defect formation and heavy carrier recombination losses. By depositing an ultrathin cadmium sulfide (CdS) precursor layer on the porous CZTS film prior to sulfurization, the PDSL approach enables active, uniform cation substitution during crystallization. The resulting pure--sulfide CZTS/ZTO devices achieved a power conversion efficiency of 12.23% at cell scale and 10.31% across a 1.00 cm² aperture area, setting a new benchmark for non--alloyed pure--sulfide kesterite thin--film photovoltaics and offering an industrially viable processing route.