Two-inch-sized perovskite crystals, CH3 NH3 PbX3 (X=I, Br, Cl), with high crystalline quality are prepared by a solution-grown strategy. The availability of large perovskite crystals is expected to transform its broad applications in photovoltaics, optoelectronics, lasers, photodetectors, LEDs, etc., just as crystalline silicon has done in revolutionizing the modern electronics and photovoltaic industries.

Organic–inorganic hybrid halide perovskites are proven to be a promising semiconductor material as the absorber layer of solar cells. However, the perovskite films always suffer from nonuniform coverage or high trap state density due to the polycrystalline characteristics, which degrade the photoelectric properties of thin films. Herein, the alkali metal ions which are stable against oxidation and reduction are used in the perovskite precursor solution to induce the process of crystallization and nucleation, then affect the properties of the perovskite film. It is found that the addition of the alkali metal ions clearly improves the quality of perovskite film: enlarges the grain sizes, reduces the defect state density, passivates the grain boundaries, increases the built‐in potential (V bi), resulting to the enhancement in the power conversion efficiency of perovskite thin film solar cell.

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Metal-organic frameworks (MOFs) provide a platform to design new heterogeneous catalysts for catalytic CO 2 reduction, but selective formation of C2 valuable liquid fuel products remains a challenge. Herein, we propose a strategy to synthesize composites by integrating MoS 2 nanosheets into hierarchically porous defective UiO-66 (d-UiO-66) to form Mo-O-Zr bimetallic sites on the interfaces between UiO-66 and MoS 2 . The active interfaces are favorable for the efficient transfer of photo-generated charge carriers and for promoting the activity, whereas, the synergy of the components at the interfaces achieves selectivity for C2 production. The d-UiO-66/MoS 2 composite facilitates the photo-catalytic conversion of gas phase CO 2 and H 2 O to CH 3 COOH under visible light irradiation without any other adducts. The evolution rate and selectivity of CH 3 COOH reached 39.0 mmol g À1 h À1 and 94 %, respectively, without any C1 products, suggesting a new approach for the design of highly efficient photocatalysts of CO 2 for C2 production. Theoretical calculations demonstrate the charge-polarized Zr-O-Mo aided the C À C coupling process with the largely reduced energy barrier.

Inorganic lead halide perovskites are attracting increasing attention due to their much better thermal stability than the organic–inorganic hybrid perovskite materials. Thus, the low power conversion efficiency (PCE) is a key issue for the inorganic lead halide perovskite solar cells (PSCs). This is mainly due to their wider bandgap and larger energy loss (Eloss) in the devices. Herein, for solving this issue, a dye molecule‐assisted engineering using the dye of 5,15‐bis(2,6‐dioctoxyphenyl)‐10‐(bis(4‐hexylphenyl)‐amino‐20‐4‐carboxyphenylethynyl)porphyrinato]zinc(II) (YD2‐o‐C8) is demonstrated. Results indicate that this molecule has a bifunctional effect, not only as a co‐sensitization layer for CsPbIBr2 with broader absorption spectrum but also reduces the Eloss by interface passivation. Specifically, the light absorption range of the photoactive layer is broadened from 600 to nearly 680 nm. At the same time, the interfacial charge recombination is highly reduced. After optimizing, the champion PCE is enhanced from 7.02% to 10.13%, and record‐high open‐circuit voltage (VOC) of 1.37 V and short‐circuit currents (JSC) of 12.05 mA cm−2 are achieved. This study opens a simple and efficient way to improve the efficiency of inorganic PSCs.

Anticounterfeiting is a vitally important issue in modern society. At present, the most commonly used luminescent anticounterfeiting technique is based on static photoluminescence (PL), which is easily counterfeited by certain substitutes. In this work, we report for the first time a dynamic PL material, Na2CaGe2O6:Tb3+. Irradiated by a portable ultraviolet (254 nm) lamp, the PL color of the material due to Tb3+ changes from the initial red to yellow and, finally, green. The investigation reveals that the dynamic PL is due to the presence of appropriate traps and the cross-relaxation effect of Tb3+ in Na2CaGe2O6. By employing this unique dynamic PL material, high-level dynamic luminescent anticounterfeiting and encryption devices can be fabricated. The dynamic PL features of the devices are easily detected using a cheap portable lamp, and at present, it is impossible for the features to be faked by any substitutes. In a virtual military scenario, the results demonstrate that the encryption device is safe and that a spy will be detected. Accordingly, this dynamic PL material could inspire more ingenious security designs.

The heterostructures of AuNPs anchored PPF-3 nanosheets by electrostatic interaction exhibit an enhancement of photocatalytic CO2 conversion under visible light by plasmon-induced resonance energy transfer.

We successfully realized layered decoding for LDPC convolutional codes designed for application in high speed optical transmission systems. A relatively short code with 20% redundancy was FPGA-emulated with a Q-factor of 5.7dB at BER of 10 -15 .