Simplified Perovskite Solar Cell with 4.1% Efficiency Employing Inorganic CsPbBr₃ as Light Absorber

Abstract

Perovskite solar cells with cost-effectiveness, high power conversion efficiency, and improved stability are promising solutions to the energy crisis and environmental pollution. However, a wide-bandgap inorganic-semiconductor electron-transporting layer such as TiO can harvest ultraviolet light to photodegrade perovskite halides, and the high cost of a state-of-the-art hole-transporting layer is an economic burden for commercialization. Here, the building of a simplified cesium lead bromide (CsPbBr ) perovskite solar cell with fluorine-doped tin oxide (FTO)/CsPbBr /carbon architecture by a multistep solution-processed deposition technology is demonstrated, achieving an efficiency as high as 4.1% and improved stability upon interfacial modification by graphene quantum dots and CsPbBrI quantum dots. This work provides new opportunities of building next-generation solar cells with significantly simplified processes and reduced production costs.

Lattice Modulation of Alkali Metal Cations Doped Cs1−xRxPbBr3 Halides for Inorganic Perovskite Solar Cells

“…These optimal Cs 1‐x R x PbBr 3 films suffer from X‐ray diffraction (XRD) characterization, as shown in Figures c, 4a, and S8, Supporting Information, three characteristic peaks (2 θ = 15.2°, 21.7°, 26.5°) assigned to (100), (110), and (111) facets of perovskite phase are detected in all films. No detection on PbBr 2 diffraction peaks suggest successful doping of alkali metal cations for high‐purity perovskite light‐absorbers . According to the calculated lattice constants for perovskites extracted from XRD characterizations, as shown in Table , it is found that a = 5.8375 Å, b = 5.8426 Å and c = 5.9034 Å for pristine CsPbBr 3 halide, while they are decreased to minimum a = 5.7143 Å, b = 5.7547 Å, c = 5.7997 Å for Rb + doped perovskite film.…”

Promoting the Hole Extraction with Co3O4 Nanomaterials for Efficient Carbon‐Based CsPbI2Br Perovskite Solar Cells

“…In order to further investigate the interfacial carrier dynamics, the TRPL decay curves for the three films were measured, as shown in Figure b. The PL decay lifetime can be obtained by the double‐exponential decay function (2): where τ 1 corresponds to the faster component of trap‐mediated nonradioactive recombination and τ 2 is the slower component related to the radiative recombination . It is noted that CsPbI 2 Br/C and CsPbI 2 Br/Co 3 O 4 /C films have smaller τ 2 values of 5.179 and 3.154 ns compared to the value of 6.835 ns for CsPbI 2 Br film, respectively.…”

“…To solve these problems, the all‐inorganic PSCs based on carbon electrode have been developed. Tang et al have fabricated all‐inorganic PSCs with the structure of FTO/CsPbBr 3 /carbon or FTO/TiO 2 /CsPbBr 3 /carbon, which have achieved an efficiency of 4.1 and 6.10%, respectively . Compared with the typical inorganic PSCs based on organic HTM and evaporated Au electrode, the carbon‐based HTM‐free inorganic PSCs have exhibited many advantages such as good stability, the low cost, simple process, and so on.…”

Highly Uniform Large-Area (100 cm2) Perovskite CH3NH3PbI3 Thin-Films Prepared by Single-Source Thermal Evaporation

“…It can be concluded that the significantly smoother and more uniform perovskite thin films prepared by the single-source evaporation is promising for large area high quality perovskite solar cells. To investigate the influence of perovskite film quality on carrier recombination character, time-resolved photoluminescence (TRPL) was carried out by measuring the PL decay of the emission peaks at 760 nm with an excitation wavelength of 532 nm, indicating the defect states and recombination process of perovskite films, as shown in and τ 2 is the slower component correlated to radiative recombination [25][26][27]. According to the perovskite life length and the diffusion coefficient of electrons and holes D, and according to the formula L D 2 = Dt e , the electron and the hole average diffusion lengths of 184 nm and 156 nm were deduced respectively, which is higher than CH 3 NH 3 PbI 3 having prepared by solution method (about 100 nm) [28].…”