Cesium Lead Halide Perovskite Nanostructures: Tunable Morphology and Halide Composition

Surface Ligand Engineering for a Lead-Free Cs3Cu2Br5 Microcrystal-Based Humidity Sensor with a Giant Response

Halide perovskites are potential humidity-detection materials due to their sensitivity to water, but the instability of traditional lead-based halide perovskites and the toxicity of Pb hinder further application in humidity sensing. Here, lead-free Cs₃Cu₂Br₅ perovskite microcrystals passivated by surface ligands (OLA and OAm) are used to prepare an environmentally friendly humidity sensor. The humidity sensing performance of the prepared sensors was tested, and the effect of surface ligands of perovskites on the performance of humidity sensors was analyzed. The results show that the impedance variations of the manufactured humidity sensors at 12 to 95% relative humidity are 10⁶Ω (OLA) and 10⁵Ω (OAm), respectively. Besides, the sensors demonstrated excellent repeatability, low hysteresis, and considerable stability at different RH values. Furthermore, the analysis of the different ligands attests that short-chain OLA is more conducive to the formation of porous films with stronger water absorption capacity, further improving the responsiveness of the sensor. By contrast, and long-chain OAm is more conducive to the formation of dense films, improving the response ability at low humidity. Additionally, the more hydrophilic OLA contributes to greater responsiveness, while the more hydrophobic OAm helps to shorten the response and recovery time.

3D hybrid perovskite solid solutions: a facile approach for deposition of nanoparticles and thin films via B-site substitution

CH₃NH₃Pb_1−xCu_xBr₃ hybrid perovskite solid solutions as nanoparticles and thin films have been fabricated.

Revisiting the Optimal Nano-Morphology: Towards Amorphous Organic Photovoltaics

Organic photovoltaic cells commonly use an active layer with a polycrystalline bulk heterojunction. However, for simplifying the fabrication process, it may be worthwhile to use an amorphous active layer to lessen the burden on processing to achieve optimal performance. While polymers can adopt amorphous phases, molecular glasses, small molecules that can readily form glassy phases and do not crystallize over time, offer an appealing alternative, being monodisperse species. Our group has developed a series of reactive molecular glasses that can be covalently bonded to chromophores to form glass-forming adducts, and this strategy has been used to synthesize glass-forming donor and acceptor materials. Herein, the results of devices incorporating these materials in either partially or fully amorphous active layers are summarized. Additionally, these molecular glasses can be used as ternary components in crystalline systems to enhance efficiency without perturbing the morphology.

Broadband emission in a new lead free all-inorganic 3D CsZnCl2I perovskite

Broadband emission was observed in new lead free all-inorganic 3D CsZnCl₂I perovskite thin films deposited by AACVD.

Fabrication of planar heterojunction CsPbBr2I perovskite solar cells using ZnO as an electron transport layer and improved solar energy conversion efficiency

Inorganic cesium lead bromoiodide based planar perovskite solar cells with ZnO electron transport layers are deposited using one step spin coating.