Mechanochemical synthesis of three double perovskites: Cs₂AgBiBr₆, (CH₃NH₃)₂TlBiBr₆ and Cs₂AgSbBr₆

Abstract

Mechanochemistry is a solvent-free, simple and fast tool for the synthesis of double perovskites.

Lead‐Free Perovskites‐Based Photonic Synaptic Devices with Logic Functions

“…The longer and shorter lifetime are attributed to the band‐to‐band radiative recombination and free exciton recombination from the conduction band or intrinsic defect levels, respectively. [ 28,32 ]…”

“…The longer and shorter lifetime are attributed to the band-to-band radiative recombination and free exciton recombination from the conduction band or intrinsic defect levels, respectively. [28,32] Figure S4 (Supporting Information) shows semilogarithmic current-voltage (I-V) characteristics of Cs 2 AgSbBr 6 -PS under conditions of dark and illumination with 400 nm light (2.5 mW cm -2 ), indicating good photosensitivity of the device. The inset in Figure S4 (Supporting Information) is the enlarged I-V curves at −0.5 to 0.5 V, which presents obvious linear current characteristics, indicating the good Ohmic contacts between the Cs 2 AgSbBr 6 and Au electrodes.…”

“…Cs 2 AgSbBr 6 has low optical bandgaps and good stability. [ 28,29 ] The resulted Cs 2 AgSbBr 6 ‐based photonic synaptic devices (Cs 2 AgSbBr 6 ‐PS) held good reproducibility and stability. The devices successfully mimicked primary synaptic behaviors including excitatory postsynaptic current (EPSC), paired pulse facilitation (PPF), short‐term memory (STM), long‐term memory (LTM), the transfer between STM and LTM, and the “learning‐forgetting‐relearning” process through the modulation of optical pulse intensity, width, and pulse number.…”

Mechanisms of mechanochemical synthesis of cesium lead halides: pathways toward stabilization of α-CsPbI3

“…The process is simple and can be performed even by manual grinding of the halides using a mortar and a pestle [31,32,[34][35][36][37][38][39][40]. This approach is especially useful in the preparation of complex perovskites [34,[40][41][42][43], which are difficult to produce by the solution processing methods due to the limited choice of suitable solvents capable of dissolving the multiple reactants [32, [44][45][46]. The mechanochemical synthesis also provides versatile pathways for modulation of B-or X-sites in perovskites [31,38,40,45,[47][48][49][50].…”

Synthesis of TlBr and Tl2AgBr3 Nanocrystals

“…Thallium (Tl) halides are used in radiation scintillators, near‐infrared (NIR) optics, and positron emission tomography applications . Double perovskite halides made with Tl, such as Cs 2 AgTlX 6 , Cs 2 Ag x Tl 1‐x BiX 6 (X=I,Br,Cl), and (CH 3 NH 3 ) 2 TlBiBr 6 , might prove useful in photovoltaic (PV) and light‐emitting diode (LED) devices . Furthermore, desire for lead‐free perovskite alternatives in optoelectronics has motivated development of various lead‐free nanocrystals based on Bi and Sb .…”