All-Inorganic Perovskite Solar Cells With Both High Open-Circuit Voltage and Stability

Abstract

Metal halide perovskite solar cells based on all-inorganic CsPbBr 3 have attracted considerable attentions recently, due to their high open-circuit voltage and good stability. However, the fabrication of CsPbBr 3 film is limited by the poor solubility of cesium precursors in organic solvents by the one-step method. Here, we successfully fabricated CsPbBr 3 film solar cells by employing colloid nanocrystal. The effects of technique parameters, including purification times, anneal temperatures, and spin-coating times on film morphology, optical spectra, and device performance are investigated in detail. The highest power conversion efficiency of 4.57% has been achieved based on a large open-circuit voltage of 1.45 V and a large short-circuit current of 9.41 mA cm −2. A large open-circuit voltage results from the reduced non-radiative energy loss channels and defect states while a large short-circuit current is related to the high conductivity induced by the removal of organic ligands with the increased nanocrystal electronic coupling. Furthermore, excellent stability in air is disclosed on the unencapsulated device suggesting the enormous potential for developing high open-circuit photovoltaic devices with high stability in future.

Investigation of Excitons Properties in Atomically Thin CsPbBr3 Perovskite Film

“…The bandgap of bulk CsPbBr 3 calculated by GW approximation is consistent with the value of experiment result. [ 35 ] However, the energy gap of CsPbBr 3 film with 2 nm is 2.84 eV, [ 25 ] that is, the bandgap value of 3L‐CsPbBr 3 is larger than 2.84 eV, which proves that the E g calculated by GW approximation is closer to the experiment result than the other two methods.…”

Fabrication of single phase CsPbBr3 films via in situ metal reaction

“…The R rec value of 40 nm Pb@CsPbBr 3 is much higher than those of other CsPbBr 3 PSCs, indicating that 40 nm Pb@CsPbBr 3 has the lowest charge recombination in the interface between electron transport layers and absorption layers owing to its excellent morphology. 36,37 The CsPbBr 3 /carbon-based PSCs were fabricated as shown in Fig. 6.…”

Structural, Thermodynamical and Electronic Properties of All-Inorganic Lead Halide Perovskites

“…The optimized lattice constants and calculated band gaps are shown in Table 1. The corresponding experimental data are also list for reference 24,36,40,[48][49][50][51][52][53][54] . The crystal structures, bond lengths and bond angles between Pb and X of α, b and γ-CsPbX3 are shown in Fig.…”

“…The bond length of Pb-I increases gradually, which lead to weakening of Pb-I interaction. As a result, the antibonding states of Pb 6s-I 5p (VBM) are suppressed 54 . Because the CBM is mainly contributed by the Pb 6p states, the influence of Pb-I bonding strength on the CBM position is relatively small.…”