Highly Stable, New, Organic‐Inorganic Perovskite (CH₃NH₃)₂PdBr₄: Synthesis, Structure, and Physical Properties

Abstract

Lead halide perovskites have attracted striking attention recently, due to their appealing properties. However, toxicity and stability are two main factors restricting their application. In this work, a less toxic and highly stable Pd-based hybrid perovskite was experimentally synthesized, after exploring different experimental conditions. This new hybrid organic-inorganic perovskite (CH NH ) PdBr was found to be an orthorhombic crystal (Cmce, Z=4) with lattice parameters a=8.00, b=7.99, c=18.89 Å. The Cmce symmetry and lattice parameters were confirmed using Pawley refinement and the atoms positions were confirmed based on DFT calculation. This perovskite compound was determined to be a p-type semiconductor, with a resistivity of 102.9 kΩ cm, a carrier concentration of 3.4 ×10 cm , and a mobility of 23.4 cm (V s) . Interestingly, XRD and UV/Vis measurements indicated that the phase of this new perovskite was maintained with an optical gap of 1.91 eV after leaving in air with a high humidity of 60 % for 4 days, and unchanged for months in N atmosphere; much more stable than most existing organic-inorganic perovskites. The synthesis and various characterizations of this work further the understanding of this (CH NH ) PdBr organic-inorganic hybrid perovskite material.

(CH3NH3)AuX4⋅H2O (X=Cl, Br) and (CH3NH3)AuCl4: Low‐Band Gap Lead‐Free Layered Gold Halide Perovskite Materials

“…Interestingly, the DSC curve shows a clear peak below this temperature (labeled T 1 ), which could be melting or structural transition of 3 before its decomposition. The observed thermal behavior exhibited by 1 , 2 and 3 are comparable to that of other hybrid halide perovskites reported in literature …”

Reduced trap density and mitigating the interfacial losses by placing 2D dichalcogenide material at perovskite/HTM interface in a dopant free perovskite solar cells

“…[6] The extrinsic environmental condition, i.e., light intensity, electric field, and temperature during device operation can promote the natal local defects towards the degradation of the active layer, thus it is paramount to extract the untrapped and detrapped carriers promptly to militate charge accumulation and recombination. [6,9,10] The apparent J-V hysteresis and poor stability originate not only from the defective active layer and disordered charge transport, but also from perovskite/charge transport layer (CTL) interfaces, and charge extracting materials. [4,11,12] The interface between the hole transport material (HTM) and the perovskite remains the vulnerable part in the device for stability as trapped charges at the interface between perovskite and charge extraction layer are responsible for the irreversible degradation caused by moisture.…”

Higher temperature order–disorder transition, electrical and optical properties of [N(C2H5)4]2Pd2Cl6compound

“…For instance, as semiconducting channels in thin film field‐effect transistors because of superior carrier mobility; as light‐emitting diodes due to the large dielectric constant difference between the organic and inorganic layers; and notably, as the photo absorber layer of solar cells owing to their high absorption coefficients, tunable optical band gaps, longer exciton diffusion lengths, etc. [ 1–7 ] Their suitability in such a broad range of applications stems from their unique composition and resultant properties. By hybridizing the organic and inorganic materials into a single organic–inorganic hybrid composite, the remarkable properties of both organic and inorganic component are integrated.…”