Search

Advances in materials science are increasingly dependent on the development of multifunctional materials capable of improving system efficiency and reducing the environmental impact. In this study, two zero-dimensional (0D) cadmium-based organic-inorganic hybrid materials (BEMPD) 2 CdBr 4 (BEMPD-Br, 1 ) and (BEMPD) 2 CdBr 2 Cl 2 (BEMPD-ClBr, 2 ) (BEMPD = 1-(2-bromoethyl)-1-methylpiperidine) were prepared by halogen doping. Compound 2 is a mixed halide in which there are two halogen sites, Cl and Br, and in a disordered state, which has a regulatory effect on the structural distortion and properties of the compound. The Curie temperatures of compounds 1 and 2 are 348 and 390 K, respectively, and the UV-vis absorption spectra showed that the direct band gaps of compounds 1 and 2 were 4.68 and 4.8 eV, respectively. In addition, room-temperature photoluminescence experiments show broadband emission peaks at 717 and 683 nm for compounds 1 and 2 , respectively, with fluorescence lifetimes of 2.414 and 3.915 μs. These 0D hybrids provide an avenue for the development of smart materials and optoelectronic devices, and also provide positive clues for manipulating the properties of organic-inorganic hybrid compounds.

The incorporation of oxygen atoms from air under aerobic conditions plays an important role in organic synthesis. Herein, Brønsted acids are found to be a two-in-one strategic catalyst to transform enamines from β-oxoamides and amines to pyrrolin-4-ones without an external photocatalyst under visible-light conditions. The Brønsted acid can inhibit the C-C bond fragmentation of the [2 + 2] adduct from enamine and 1 O 2 , but most importantly, it can form photosensitizers with enamine and pyrrolin-4-one product by acidochromism to promote the 1 O 2 generation.

Modification of photocatalyst reactivity through intermolecular interactions represents a straightforward and convenient strategy for catalyst designation. Herein, we reported that upon the addition of B(C 6 F 5 ) 3 ·H 2 O, the oxidation potential of quinoxalinone increased remarkably, enabling the photoredox aerobic oxidation of alcohol, thiols, and alkenes toward carbonyl compounds and dithioethers under visible light conditions. Mechanistic studies, including X-ray structure analysis, cyclic voltammetry, electron paramagnetic resonance measurements, UV-vis absorption, and fluorescence spectra, revealed that the quinoxalinone-B(C 6 F 5 ) 3 ·H 2 O combo could serve as a versatile photocatalyst for both energy transfer and single electron transfer processes.

Excess lead iodide (PbI 2 ) plays a crucial role in passivating the defects of perovskite films and boosting the power conversion efficiency (PCE) of perovskite solar cells (PSCs). However, the photolysis of PbI 2 is easily triggered by light illumination, which accelerates the decomposition of perovskite materials and weakens the long-term stability of PSCs. Herein, the high light tolerance of lead iodide (PbI 2 ) is reported by introducing an electron-donor molecule, namely, 2-thiophenecarboxamide (2-TCAm), to strengthen the [PbX 6 ] 4- frame. Characterization reveals that the retarded decomposition of PbI 2 is attributed to the interactions between Pb 2+ and the organic functional groups in 2-TCAm as well as the optimized distribution of PbI 2 . The crystallization and morphology of 2-TCAm-doped perovskite films are improved simultaneously. The 2-TCAm-based PSCs achieve a 16.8% increase in PCE and nearly 12 times increase in the lifetime as compared to the reference device. The demonstrated method provides insight into the stability of PbI 2 and its influence on PSCs.

All-inorganic perovskite cesium lead iodide/bromide (CsPbI 2 Br) is considered as a robust absorber for perovskite solar cells (PSCs) because of its excellent thermal stability that guarantees its long-term operation stability. Efficient CsPbI 2 Br PSCs are available when obtaining low energy loss, which needs efficient charge generation, less charge recombination, and balanced charge extraction. However, numerous traps in perovskites hinder the photon-electron conversion process. Herein, hierarchical manipulation of charge recombination is proposed for CsPbI 2 Br PSCs featuring low energy loss. Nonselective trap reduction and selective halogen vacancy passivation are performed using 2,2'-(ethylenedioxy)diethylamine and phenylbutylammonium iodide for the bottom and top contacts, respectively. Because of all-around suppressed charge recombination, balanced charge extraction and suppressed hysteresis are realized. The champion PSC achieves an open-circuit voltage of 1.30 eV, a fill factor of 80.2%, and a power conversion efficiency of 16.6% that is 28.6% higher than that of the reference device. Moreover, the thermostability of PSCs is simultaneously enhanced because of the limited defect-assisted degradation.

Electrochemical conversion of N 2 to NH 3 under ambient conditions is a promising and environmentally friendly route compared with the CO 2 -emitting and energy-intensive Haber-Bosch process. Nevertheless, due to ultrahigh stability of N 2 , it is urgent to explore efficient catalysts to weaken and activate the N≡N bond. Here, we report the Mo-doped iron phosphide (Mo-FeP) nanosphere as a valid transition-metal-based catalyst for electrochemical N 2 -to-NH 3 fixation under ambient conditions. This catalyst exhibits excellent catalytic performance with a NH 4 + yield rate (13.1 μg h -1 mg -1 ) and Faradaic efficiency (7.49%) at -0.3 and -0.2 V vs reversible hydrogen electrode (RHE), respectively. However, the FeP catalyst without doped Mo species displays weak catalytic performance. We found that the better catalytic performance of Mo-FeP might be due to the doping of Mo species, which is favorable for the polarization of adsorbed N 2 molecules, making the N≡N bond more viable to dissociate.