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... Organic molecule doping is one of the main strategies to enhance the performance and sustainability of organometal halide perovskite polycrystalline films. However, the mechanisms for interpreting organic molecule doping are poorly understood, limiting the development of perovskite solar cells (PSCs). Herein, we revisit regular perovskite films and study the doping effects of two typical organic m ...
... Thin films of rare earth metal oxyhydrides show a photochromic effect, the precise mechanism of which is yet unknown. Here, we made thin films of NdH₃–₂ₓOₓ and show that we can change the band gap, crystal structure, and photochromic contrast by tuning the composition (O²–:H–) via the sputtering deposition pressure. To protect these films from rapid oxidation, we add a thin ALD coating of Al₂O₃, w ...
... Two new pincer-type bisnitroxides have been synthesized, where tetramethylenedioxy and o-xylylenedioxy are chosen as a bridge between the p-position of two tert-butyl phenyl nitroxide moieties. The X-ray crystal structure analysis clarified the linear and U-shaped molecular structures for the former and latter compounds, respectively. In the toluene solution ESR of the tetramethylenedioxy derivati ...
... To investigate the post-irradiation oxidation process, different polyethylenes (UHWPE, HDPE, LDPE) were irradiated by gamma rays in Ar and then exposed to air. The effect of crystalline structure on the post-irradiation oxidation process was evaluated combined by FTIR with EPR technique. Crystallinity and thickness of lamellae play a major role on post-irradiation oxidation, largely affecting the ...
crystalstructure, etc ; hysteresis; silicon; transmittance; Show all 4 Subjects
Abstract:
... Organic–inorganic hybrid perovskite solar cells (PSCs) have attracted enormous research attention due to their high efficiency and low cost. However, most of the PSCs with high efficiencies still need expensive organic materials as their hole-transport layer (HTL). Obviously, the highly expensive materials go against the low-cost concept of advanced PSCs. In this regard, inorganic NiOₓ was conside ...
crystalstructure, etc ; environment; nanoplastics; polyethylene; Show all 4 Subjects
Abstract:
... When plastics enter the environment, they are exposed to abiotic and biotic impacts, resulting in degradation and the formation of micro- and nanoplastic. Microplastic is ubiquitous in every environmental compartment. Nevertheless, the underlying degradation processes are not yet fully understood. Here, we studied the abiotic degradation of commonly used semi-crystalline, low-density polyethylene ...
crystalstructure, etc ; halogens; photosensitivity; potassium; Show all 4 Subjects
Abstract:
... Defect accumulation and nonradiative recombination at the interface of the electron-transport layer (ETL) and the photosensitive layer are inevitable obstacles to efficient and stable perovskite solar cells (PSCs). Herein, we reported a dual-effect interface modification strategy that employs potassium tetrafluoroborate (KBF₄) molecules for the simultaneous passivation of the SnO₂/perovskite inter ...
crystalstructure, etc ; biocompatible materials; encapsulation; Show all 3 Subjects
Abstract:
... Crystalline materials are increasingly being used as platforms for encapsulating proteins to create stable, functional materials. However, the uptake efficiencies and stimuli-responsiveness of crystalline frameworks are limited by their rigidities. We have recently reported a new form of materials, polymer-integrated crystals (PIX), which combine the structural order of protein crystals with the d ...
crystalstructure, etc ; dissociation; energy; separation; Show all 4 Subjects
Abstract:
... Two nonfused ring electron acceptors (NFREAs), BTh-OC8-2F and DTh-OC8-2F, with different molecular shapes are designed and synthesized. Both acceptors can form planar molecular shapes by the assistance of S···O intramolecular interactions. Differently, BTh-OC8-2F, with a linear molecular backbone and two trans-arranged side chains at the core unit, exhibits much stronger crystallinity than DTh-OC8 ...
crystalstructure, etc ; molecular conformation; phenothiazine; Show all 3 Subjects
Abstract:
... The design of new aggregation-induced emission luminogens (AIEgens) has aroused continuous attention. The relationship between structure and performance plays an important role in guiding such efforts. In this contribution, two R–D–A- and R–D−π–A-type AIEgens were facilely designed and synthesized, that is, DPE-PTZ-CN and DPE-PTZ-PCN, with diphenylethylene as the twisted rotor structure (R), pheno ...
crystalstructure, etc ; chemical communication; imidazole; materials; Show all 4 Subjects
Abstract:
... Here we show a time-programmed and autonomous synthesis of zeolitic imidazole framework-8 (ZIF-8) using a methylene glycol–sulfite clock reaction. The induction period of the driving clock reaction, thus, the appearance of the ZIF-8 can be adjusted by the initial concentration of one reagent of the chemical clock. The autonomously synthesized ZIF-8 showed excellent morphology and crystallinity. ...
Sizhuo Yang; Chongqing Yang; Chaochao Dun; Haiyan Mao; Rebecca Shu Hui Khoo; Liana M. Klivansky; Jeffrey A. Reimer; Jeffrey J. Urban; Jian Zhang; Yi Liu
crystalstructure, etc ; heterocyclic compounds; imines; porosity; Show all 4 Subjects
Abstract:
... Covalent organic frameworks (COFs) show great potential for many advanced applications on account of their structural uniqueness. To address the synthetic challenges, facile chemical routes to engineer the porosity, crystallinity, and functionality of COFs are highly sought after. Herein, we report a synthetic approach that employs the Cadogan reaction to introduce nitrogen-containing heterocycles ...
crystalstructure, etc ; chemical bonding; dimerization; rapamycin; Show all 4 Subjects
Abstract:
... Chemically induced dimerization (CID) is used to induce proximity and result in artificial complex formation between a pair of proteins involved in biological processes in cells to investigate and regulate these processes. The induced heterodimerization of FKBP fusion proteins by rapamycin and FK506 has been extensively exploited as a chemically induced dimerization system to regulate and understa ...
crystalstructure, etc ; crosslinking; crystallites; crystallization; rubber; Show all 5 Subjects
Abstract:
... The clarification of the role of organic components in cuttlebone particles on the morphological and mechanical properties in terms of the strain-induced crystallization (SIC) of peroxide cross-linked cuttlebone/natural rubber (NR) composites was revealed for the first time in this study. The organic components in cuttlebone particles affected the increased bound rubber layers and the decreased ru ...
crystalstructure, etc ; ambient temperature; thermal conductivity; Show all 3 Subjects
Abstract:
... Prior experimental work showed that Bi₂Se₃, as a sister compound of the best room-temperature thermoelectric material Bi₂Te₃, has remarkably improved thermoelectric performance by Sb–Br codoping. But the relationship between its crystalline structure and thermoelectric properties is still unclear to date. Here, we use first-principles calculations to explore the possible reasons for such improveme ...
crystalstructure, etc ; oxygen; reaction kinetics; temperature; Show all 4 Subjects
Abstract:
... A YBaCo₄O₇ oxygen storage material has been synthesized by the glycine-complex decomposition method at a low temperature of 800 °C and its crystal structure and reaction kinetics were investigated. This sample showed the highest storage/release speed among all the reported YBaCo₄O₇₊δ materials. ...
crystalstructure, etc ; cations; energy; neutron diffraction; Show all 4 Subjects
Abstract:
... Solid electrolytes are at the heart of future energy storage systems. Li-bearing argyrodites are frontrunners in terms of Li⁺ ion conductivity. Although many studies have investigated the effect of elemental substitution on ionic conductivity, we still do not fully understand the various origins leading to improved ion dynamics. Here, Li₆₊ₓP₁–ₓGeₓS₅I served as an application-oriented model system ...
crystalstructure, etc ; biomimetics; porphyrins; water solubility; Show all 4 Subjects
Abstract:
... Iron water-soluble porphyrins have been long used as biomimetic compounds for modelling the active sites found in heme-enzymes. In this regard, the anionic porphyrin [Feᴵᴵᴵ(TPPS)]³─ and its coordination complexes have been repeatedly chosen as suitable water-soluble platforms for bioinorganic chemistry studies. In this work we report for the first time the crystal structure of the water-soluble ni ...
crystalstructure, etc ; coordination polymers; ligands; vanadium; Show all 4 Subjects
Abstract:
... Hydrothermal synthesis, crystal structure and properties of a new heterometallic coordination polymer [(VO(terpy))₄(MoO₄)₂(Mo₈O₂₆)]·2H₂O (1) (terpy = 2,2′;6′,2″-terpyridine) are reported. Compound 1 contains two crystallographically unique vanadium(IV) atoms, bonded to a terminal oxido ligand and further coordinated to a terpy ligand. The three N atoms of terpy occupy the meridional sites of a dis ...
crystalstructure, etc ; cathodes; manganese dioxide; temperature; Show all 4 Subjects
Abstract:
... The obtainment of low-cost, easily prepared and high-powered LiMn₂O₄ is the key to achieve its wide application in various electronic devices. In this work, a mild and easily scaled molten salt method (KCl@LiCl) is utilized to convert commercial MnO₂ to the high-performance LiMn₂O₄. At the same reaction temperature, the molten salt method leads to the formation of K⁺-doped LiMn₂O₄ with higher crys ...