Sub-1.4eV bandgap inorganic perovskite solar cells with long-term stability

Abstract

State-of-the-art halide perovskite solar cells have bandgaps larger than 1.45 eV, which restricts their potential for realizing the Shockley-Queisser limit. Previous search for lowbandgap (1.2 to 1.4 eV) halide perovskites has resulted in several candidates, but all are hybrid organic-inorganic compositions, raising potential concern regarding device stability. Here we show the promise of an inorganic low-bandgap (1.38 eV) CsPb 0.6 Sn 0.4 I 3 perovskite stabilized via interface functionalization. Device efficiency up to 13.37% is demonstrated. The device shows high operational stability under one-sun-intensity illumination, with T 80 and T 70 lifetimes of 653 h and 1045 h, respectively (T 80 and T 70 represent efficiency decays to 80% and 70% of the initial value, respectively), and long-term shelf stability under nitrogen atmosphere. Controlled exposure of the device to ambient atmosphere during a long-term (1000 h) test does not degrade the efficiency. These findings point to a promising direction for achieving low-bandgap perovskite solar cells with high stability.

Improving the Stability and Optoelectronic Properties of All Inorganic Less‐Pb Perovskites by B‐Site Doping for High‐Performance Inorganic Perovskite Solar Cells

“…Hu et al reported that the stability and properties of CsPb 0.6 Sn 0.4 I 3 perovskite film were remarkably improved through an interface‐functionalization strategy comprising incorporating SnF 2 ·3FACl additive into CsPb 0.6 Sn 0.4 I 3 perovskite precursor and spin‐coating 4‐(aminomethyl) piperidinium diiodide (4AMP)I 2 on the surface of CsPb 0.6 Sn 0.4 I 3 perovskite film. [ 66 ] The introduction of SnF 2 ·3FACl into perovskite precursor decreased the Sn‐related defects, and the coating of (4AMP)I 2 layer on perovskite film passivated the surface defects and protected the perovskite film from the moisture. The as‐fabricated CsPb 0.6 Sn 0.4 I 3 PSC achieved a high PCE of 13.37% with a J sc of 25.87 mA cm −2 and showed a good operational stability.…”

“…[ 68 ] Copyright 2014, American Chemical Society), and d) CsPb 0.6 Sn 0.4 I 3 ‐based PSC in dry ambient environment (RH: below 20%) (Reproduced with permission. [ 66 ] Copyright 2020, Springer Nature).…”

Chemically Stable Black Phase CsPbI3 Inorganic Perovskites for High‐Efficiency Photovoltaics

“…Replacing the organic components by inorganic cation cesium (Cs) can be used to tune the bandgap, and more importantly, it has been considered as an effective method to solve the organic volatility issue. [ 15–20 ] The recent rapid progress of inorganic PSCs also demonstrated the great potential of inorganic perovskites as one of the most promising candidates for thermodynamically stable and high‐efficiency PSCs. [ 21 ] Among these inorganic perovskites, CsPbI 3 inorganic perovskite with the suitable bandgap of ≈1.7 eV is most promising for both high‐efficiency single‐junction perovskite photovoltaic (PV) and wide‐bandgap top‐cell tandem with other narrow‐bandgap commercialized solar cells, such as silicon and copper indium gallium diselenide solar cells.…”

Sn/Pb binary metal inorganic perovskite: a true material worthy of trust for efficient and stable photovoltaic application

“…The elements of Sn and Pb within the same main group have similar ns 2 np 2 electronic configuration [6][7][8][9]. Especially, the Snbased perovskites are promising for solar energy harvesting in view of ideal optical bandgaps (1.2-1.4 eV), high optical absorption coefficient as well as high carrier mobility (~585 cm 2 V À1 s À1 ) [10,11].…”

“…Significantly, the PCE can go beyond 33% by narrowing the absorbers' bandgap to 1.2-1.4 eV. For example, theoretical calculation shows that the efficiency is maximum to 33.4% for a single CsPb 0.6 Sn 0.4 I 3 semiconductor at a bandgap of 1.38 eV for AM 1.5G solar spectrum [8]. The Goldschmidt tolerance factor…”