Optimal intermediate adducts regulate low-temperature CsPbI₂Br crystallization for efficient inverted all-inorganic perovskite solar cells

Abstract

The emerging inorganic CsPbI2Br perovskite is regarded as a promising candidate for future photovoltaics due to its superior photo-physical property and thermal stability, but it usually requires a high fabrication...

Lanthanide Stabilized All-Inorganic CsPbI2Br Perovskite Solar Cells with Superior Thermal Resistance

“…57 The concentration of halide plumbates in the solution can be quantitatively characterized by comparing the UV light absorption at 270−340 nm. 58 As clearly shown in Figure S4, the UV absorption was significantly reduced in the Eu(Ac) 3doped precursor solution. We speculated that the incorporated Eu 3+ can associate with the negatively charged ions and generate a type of Eu−PbX 2 adduct with a reduced concentration of halide plumbate in the solution (Figure 1d).…”

“…In particular, it is generally believed that the quality of perovskite thin films is strongly related to the chemical states of the precursor solution, and a large amount of negatively charged mobile halide ions (e.g., I – , Br – ) or halide plumbates (e.g., PbX 3 – , PbX 4 2– , PbX 6 4– , X = I, Br) in the precursor solution can bring numerous defect states or form δ-phase perovskite in the as deposited thin films . The concentration of halide plumbates in the solution can be quantitatively characterized by comparing the UV light absorption at 270–340 nm . As clearly shown in Figure S4, the UV absorption was significantly reduced in the Eu­(Ac) 3 -doped precursor solution.…”

Synergistic Effect of Defect Passivation and Crystallization Control Enabled by Bifunctional Additives for Carbon-Based Mesoscopic Perovskite Solar Cells

“…For the purpose of detecting the chemical interaction between biuret molecules and perovskite components in the precursor solution, liquid-state 1 H NMR spectroscopy characterizations were performed by dissolving biuret, MAI, and PbI 2 in deuterated dimethyl sulfoxide- d 6 . As illustrated in Figure a, the characteristic peaks at 6.78 and 8.50 ppm were related to the typical hydrogen bond signals of −NH 2 and −NH– in biuret . When biuret was added in PbI 2 solution, pronounced position shifts were observed for the two characteristic peaks, implying a strong chemical interaction between biuret and PbI 2 due to the formation of hydrogen bonds between −NH 2 and halide ions and the highly bonded Pb–O chelate compound between the neighboring double CO and Pb 2+ .…”

Unraveling All‐Inorganic CsPbI3 and CsPbI2Br Perovskite Thin Films Formation – Black Phase Stabilization by Cs2PbCl2I2 Addition and Flash‐Annealing

“…CsPbI 2 Br (E g ∼1.9 eV) is more stable than CsPbI 3 in ambient conditions, the latter being thus generally processed under nitrogen conditions to minimize the yellow phase. Preparation of such phase at low temperature is already well studied in the literature [15,16] . Understanding the thermal behavior of CsPbI 2 Br and stabilizing its black phase would also be an interesting opportunity to facilitate its use for photovoltaic devices.…”