Lead‐free Perovskite Materials (NH₄)₃Sb₂I_xBr_9−x

Abstract

Af amily of perovskitel ight absorbers (NH 4 ) 3 Sb 2 I x Br 9Àx (0 x 9) was prepared. These materials show good solubility in ethanol, al ow-cost, hypotoxic, and environmentally friendly solvent. The light absorption of (NH 4 ) 3 Sb 2 I x Br 9Àx films can be tuned by adjusting Ia nd Br content. The absorption onset for (NH 4 ) 3 Sb 2 I x Br 9Àx films changes from 558 nm to 453 nm as xc hanges from 9t o0 . (NH 4 ) 3 Sb 2 I 9 single crystals were prepared, exhibiting ah ole mobility of 4.8 cm 2 V À1 s À1 and an electron mobility of 12.3 cm 2 V À1 s À1 .( NH 4 ) 3 Sb 2 I 9 solar cells gave an open-circuit voltage of 1.03 Vand apower conversion efficiency of 0.51 %.

Progress and Perspective in Low‐Dimensional Metal Halide Perovskites for Optoelectronic Applications

“…Apart from the divalent metal cations that are applied to form <100> orientated layered perovskite structures, some trivalent metal cations such as Bi 3+ , Sb 3+ , can also be employed to construct 2D perovskite derivatives along <111> orientation adopting a general formula of A 3 B 2 X 9 . A typical example is (NH 4 ) 3 Sb 2 I 9 , which is derived from an assumed 3D parental perovskite (NH 4 ) 3 Sb 3 I 9 by removing 1/3 of metal cations to meet the requirement of charge balance (Figure c) . Similarly, (CH 3 NH 3 ) 3 Bi 2 Br 9 , (NH 2 (CH 3 ) 2 ) 3 Sb 2 Cl 9 , (NH(CH 3 ) 3 ) 3 Sb 2 Cl 9 are confirmed with the preference of forming layered structures .…”

“…Layered crystal structure of (a) (C n H 2 n +1 NH 3 ) 2 PbI 4 ( n = 18) with bulk alkylammonium cation. Reproduced with permission, Copyright 2010, American Chemical Society, (b) (C 6 H 11 NH 3 ) 2 PbBr 4 with cycloalkylammonium cation, Reproduced with permission, Copyright 2009, the Royal Society of Chemistry, (c) (NH 4 ) 3 Sb 2 I 9 single crystal with trivalent antimony cation, Reproduced with permission, Copyright 2017, Wiley‐VCH, (d) MA 2 CuCl 2 Br 2 with divalent copper cation, Reproduced with permission, Copyright 2015, American Chemical Society, (e) (C 6 H 5 C 2 H 4 NH 3 ) 2 GeI 4 with divalent germanium cation, Reproduced with permission, Copyright 2017, American Chemical Society, (f) MA 2 Pb(SCN) 2 I 2 with thiocyanate anion, Reproduced with permission, Copyright 2016, American Chemical Society.…”

“…Later on, a planar heterojunction solar cell with a 0D perovskite derivative (CH 3 NH 3 ) 3 Sb 2 I 9 light‐absorber layer delivered a PCE of ≈0.5% with a decent V oc of 890 mV and a low J sc of ≈1 mA cm −2 (Figure c) . Furthermore, by incorporating a smaller NH 4 + cation, (NH 4 ) 3 Sb 2 I 9 films and single crystals with a 2D crystal structure were synthesized, and the fabricated Sb‐based perovskite solar cells give a high V oc of 1.03 V (Figure d) . Although the fabricated bismuth‐ and antimony‐based lead‐free perovskite solar cells can deliver a comparable V oc , their relatively low PCE is still an open challenge to be addressed in the future.…”

Potential Substitutes for Replacement of Lead in Perovskite Solar Cells: A Review

“…The MA 3 Sb 2 I 9 single crystals have high absorption coefficient greater than 10 5 cm −1 at absorption peak wavelengths. The absorption onset for [ x = 0, 3, 6] in MA 3 Sb 2 I x Br 9− x films are 453, 486, and 516 nm with a direct bandgap of 2.78, 2.66, and 2.49 eV, respectively . Lead‐free perovskites do possess suitable carrier diffusion lengths and minority charge carrier lifetimes exhibiting photovoltaic performance.…”

“…These films achieved a SPCE of 2% . Similarly, Zuo and Ding synthesized a family of perovskite light absorbers (NH 4 ) 3 Sb 2 I x Br 9− x (0 ≤ x ≤ 9) . These materials display good solubility in ethanol.…”