Beyond 11% Efficiency: Characteristics of State‐of‐the‐Art Cu₂ZnSn(S,Se)₄ Solar Cells

Phase-transition-driven growth of compound semiconductor crystals from ordered metastable nanorods

“…The wurtzite nanorods used for this study had a Cu-poor and Zn-rich composition which has lead to highest the solar cell power conversion efficiencies in the past [8,11]. To study the influence of the composition on the grain growth, also nanorods with Cu-rich composition were synthesized and a similar annealing study was performed.…”

“…The nanorods are re-dispersed in anhydrous toluene and stored in a glove box for the further experiment. The as-synthesized nanorod have a Cu/(Zn + Sn) ratio of 0.8 and a Zn/Sn ratio of 1.2, which is close to the thin film photovoltaic device with highest reported power conversion efficiencies [8,11]. For the copper-rich nanorod sample (Cu/(Zn+Sn)=1.05 and Zn/Sn=1]), copper(II) acetylacetonate (1.05 mmol), Zinc acetate (0.5 mmol), Tin(IV) acetate (0.5 mmol), TOPO (3.5 mmol), 10 mL of 1-octadecene and thiols mixture (0.25 mL 1-DDT and 1.75 mL t-DDT) were used.…”

Engineering colloidal quantum dot solids within and beyond the mobility-invariant regime

“…Recent advances in perovskite solar cells, in which an order of magnitude improvement in diffusion length enabled drastic PCE improvements on a planar architecture 60 , are consistent with this view. Improvements in PCE beyond these projections will require addressing the suboptimal open circuit voltage values, currently observed in all types of solution-processed thin-film PV: CQDs 5 , perovskites 60 , copper indium gallium selenide (CIGS) 61 , copper zinc tin sulfide (CZTS) 62 and polymers 63 .…”

Ordering-induced direct-to-indirect band gap transition in multication semiconductor compounds

“…This is because they contain relatively earth abundant elements, are easy to grow, and have suitable direct band gap energies in the range of 1 to 1.5 eV at their ground state, [1][2][3][4][5] which are optimal for single junction solar cell applications. 3,6 However, despite the recent extensive study and rapid progress in development of this new solar cell technology, its power conversion efficiency is still lower than the more mature technologies, such as binary CdTe or ternary Cu(In 1-x Ga x )Se 2 (CIGSe) based solar cells.…”