The exploration of new efficient OER electrocatalysts based on nonprecious metals and the understanding of the relationship between activity and structure of electrocatalysts are important to advance ...electrochemical water oxidation. Herein, we developed an efficient OER electrocatalyst with nickel boride (Ni3B) nanoparticles as cores and nickel(II) borate (Ni‐Bi) as shells (Ni‐Bi@NB) via a very simple and facile aqueous reaction. This electrocatalyst exhibited a small overpotential of 302 mV at 10 mA cm−2 and Tafel slope of 52 mV dec−1. More interestingly, it was found that the OER activity of Ni‐Bi@NB was closely dependent on the crystallinity of the Ni‐Bi shells. The partially crystalline Ni‐Bi catalyst exhibited much higher activity than the amorphous or crystalline analogues; this higher activity originated from the enhanced intrinsic activity of the catalytic sites. These findings open up opportunities to explore nickel(II) borates as a new class of efficient nonprecious metal OER electrocatalysts, and to improve the electrocatalyst performance by modulating their crystallinity.
A new winner! Crystallinity‐dependent activity was demonstrated on a new efficient electrocatalyst for the oxygen evolution reaction (OER) which consists of a nickel(II) borate thin layer on nickel boride (NB) nanoparticles (Ni‐Bi@NB) (see figure). The partially crystalline Ni‐Bi catalyst exhibits excellent OER performance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The emergence of cesium lead iodide (CsPbI3) perovskite solar cells (PSCs) has generated enormous interest in the photovoltaic research community. However, in general they exhibit low power ...conversion efficiencies (PCEs) because of the existence of defects. A new all‐inorganic perovskite material, CsPbI3:Br:InI3, is prepared by defect engineering of CsPbI3. This new perovskite retains the same bandgap as CsPbI3, while the intrinsic defect concentration is largely suppressed. Moreover, it can be prepared in an extremely high humidity atmosphere and thus a glovebox is not required. By completely eliminating the labile and expensive components in traditional PSCs, the all‐inorganic PSCs based on CsPbI3:Br:InI3 and carbon electrode exhibit PCE and open‐circuit voltage as high as 12.04% and 1.20 V, respectively. More importantly, they demonstrate excellent stability in air for more than two months, while those based on CsPbI3 can survive only a few days in air. The progress reported represents a major leap for all‐inorganic PSCs and paves the way for their further exploration in order to achieve higher performance.
A new all‐inorganic perovskite material, CsPbI3:Br:InI3, is prepared through defect engineering of CsPbI3. This new perovskite retains the same bandgap as CsPbI3, but with intrinsic defect concentration largely suppressed. Moreover, it can be prepared in an extremely high humidity atmosphere. By completely eliminating the labile and expensive components in traditional perovskite solar cells (PSCs), these all‐inorganic PSCs exhibit high photovoltaic performances.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A new type of cobalt(II)-doped carbon dots (CCDs) have been fabricated and used successfully for sensing Cr(VI) ions on the basis of photoluminescence quenching. The structural characterization of ...as-obtained CCDs was thoroughly performed by transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) and X-ray photoelectron (XPS) spectroscopy. The optical properties were also determined by absorption and fluorescence spectra. By recording 3D fluorescence spectrum, a unique intra-particle Förster resonance energy transfer (FRET) system was investigated. In addition, fluorescence quenching of CCDs was observed in the presence of Cr(VI) ions due to inner filter effect. A good linear relationship between the concentration of Cr(VI) ions and fluorescent intensity was obtained in the range from 5μM to 125μM (R2=0.99), and the limit of detection was calculated as 1.17μM (0.12ppm for Cr(VI)). Importantly, this method was capable of rapidly detecting Cr(VI) ions in tap water and fish samples, which may be helpful in risk reduction of intake Cr(VI) contamination from water and seafood.
•Cobalt(II)-doped carbon dots (CCDs) have been fabricated.•CCDs were used for Cr(VI) sensing based on photoluminescence quenching.•The structural characterization of as-obtained CCDs was thoroughly investigated.•The CCDs was capable of rapidly detecting Cr(VI) in tap water and fish samples.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Long‐term instability and possible lead contamination are the two main issues limiting the widespread application of organic–inorganic lead halide perovskites. Here a facile and efficient ...solution‐phase method is demonstrated to synthesize lead‐free Cs2SnX6 (X = Br, I) with a well‐defined crystal structure, long‐term stability, and high yield. Based on the systematic experimental data and first‐principle simulation results, Cs2SnX6 displays excellent stability against moisture, light, and high temperature, which can be ascribed to the unique vacancy‐ordered defect‐variant structure, stable chemical compositions with Sn4+, as well as the lower formation enthalpy for Cs2SnX6. Additionally, photodetectors based on Cs2SnI6 are also fabricated, which show excellent performance and stability. This study provides very useful insights into the development of lead‐free double perovskites with high stability.
The lead‐free perovskite Cs2SnX6 (X = Br, I) with a well‐defined vacancy‐ordered defect‐variant crystal structure is synthesized via a facile and efficient solution route. Ascribed to the stable chemical composition and the lower formation enthalpy, Cs2SnX6 displays excellent stability against moisture, light, and high temperature. Photodetectors based on Cs2SnX6 exhibit remarkable performance and excellent stability.
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Oxygen activation plays a crucial role in many important chemical reactions such as oxidation of organic compounds and oxygen reduction. For developing highly active materials for oxygen activation, ...herein, we report an atomically dispersed Pt on WO3 nanoplates stabilized by in situ formed amorphous H2WO4 out‐layer and the mechanism for activating molecular oxygen. Experimental and theoretical studies demonstrate that the isolated Pt atoms coordinated with oxygen atoms from WO6 and water of H2WO4, consequently leading to optimized surface electronic configuration and strong metal–support interaction (SMSI). In exemplified reactions of butanone oxidation sensing and oxygen reduction, the atomic Pt/WO3 hybrid exhibits superior activity than those of Pt nanoclusters/WO3 and bare WO3 as well as enhanced long‐term durability. This work will provide insight into the origin of activity and stability for atomically dispersed materials, thus promoting the development of highly efficient and durable single atom‐based catalysts.
Single atom‐based catalysts: Atomically dispersed Pt species have been stabilized by an in situ formed amorphous H2WO4 layer. The Pt atoms were coordinated by oxygen atoms from the WO6 octahedra of H2WO4 and water molecules. A strong metal–support interaction was observed between the Pt atoms and the oxide atoms of H2WO4, which resulted in a superior activity and stability of the Pt atoms for the oxygen activation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Metal‐free ultralong organic phosphorescence (UOP) materials have attracted significant attention owing to their anomalous photophysical properties and potential applications in various fields. Here, ...three pyrimidine‐based organic luminogens, 9‐(pyrimidin‐2‐yl)‐9H‐carbazole, 9‐(4,6‐dimethylpyrimidin‐2‐yl)‐9H‐carbazole, and 9‐(5‐bromopyrimidin‐2‐yl)‐9H‐carbazole are designed and synthesized, which show efficient yellow UOP with the longest lifetimes up to 1.37 s and the highest absolute phosphorescence quantum yields up to 23.6% under ambient conditions. Theoretical calculations, crystal structures, and photophysical properties of these compounds reveal that intramolecular hydrogen bonding, intermolecular π–π interactions, and intermolecular electronic coupling are responsible for forming dimers and generating highly efficient UOP. Their efficacy as solid materials for data encryption is demonstrated.
Highly efficient ultralong organic phosphorescence luminogens are developed by the synergistic effect of intermolecular π–π stacking, intermolecular electronic coupling, and intramolecular hydrogen bonding. The pyrimidine‐based luminogens exhibit the longest phosphorescence lifetime of 1.37 s and the highest absolute phosphorescence quantum efficiency of 23.6%, respectively, which are rarely reported.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Polyethylene film is the most widely used plastic film in agricultural production activities, and its depolymerization products are mainly polyethylene-particles (PE-particles) of different molecular ...weights. However, the impact of the molecular weights of the PE-particles on soil-crop microenvironment has not been elucidated. In this study, a potted microcosmic simulation system was used to evaluate the impact of low, medium and high molecular weight PE-particles on soil metabolism, microbial community structure, and crop growth. There were obvious differences in the shape and surface microstructure of PE-particles with different molecular weights. Soil sucrase and peroxidase had significant responses to PE-particles of different molecular weights. In the rhizosphere, the number of microorganisms and the microbial alpha diversity index increased with increasing PE-particles molecular weight. Rhizobacter, Nitrospira, and Sphingomonas were the dominant microorganisms induced by PE-particles to regulate the metabolism of elements. Carbohydrate and amino acid contents in rhizosphere soils were the key factors affecting the species abundance of Lysobacter, Polyclovorans, Rhizobacter, and Sphingomonas. In plants, PE-particles treatment reduced the plant biomass and photosynthetic rate and disrupted normal mineral nutrient metabolism. Different molecular weight PE-particles may therefore have adverse effects on the soil-plant system.
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•Soil sucrase and peroxidase had significant responses to PE-particles of different molecular weights.•Microbial alpha diversity index gradually increased with increasing PE-particles molecular weight.•Carbohydrate and amino acid contents in the rhizosphere soil were the key factors affecting the species abundance.•PE-particles reduced plant biomass and photosynthetic rate and interfered with mineral nutrient metabolism.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Room‐temperature phosphorescence (RTP) was realized for the first time in a polyoxometalate‐based charge‐transfer (CT) hybrid material bearing polyoxometalates (POMs) as electron‐donors (D) and rigid ...naphthalene diimides (NDIs) as electron‐acceptors (A), meanwhile, this hybrid material displayed photochromism as well. The significant D‐A anion–π interaction induced an additional through‐space charge‐transfer pathway. The resulting suitable D‐A CT states can efficiently bridge the relatively large energy gap between the NDI‐localized 1π–π* and 3π–π* states and thus trigger the ligand‐localized phosphorescence (3π–π*).
A unique polyoxometalate‐based charge‐transfer complex displays both photochromism and room‐temperature phosphorescence in ambient conditions, which are mainly attributable to the charge transfer behaviors induced by unorthodox anion–π interactions. The strategy of introducing intermolecular charge‐transfer states may open up new opportunities for developing efficient organic–inorganic hybrid photofunctional materials.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
To manipulate the photocatalytic activities of BiOCl photocatalysts, doping and heterojunction engineering are simultaneously adopted. Herein, the photocatalysts Sm 3+ -doped BiOCl and BiOCl:Sm 3+ @ ...y g-C 3 N 4 were designed, in which their phase structure, morphology, optical properties and photocatalytic activities were systematically discussed. Excited at 408 nm, red emissions are seen from Sm 3+ -doped BiOCl microplates and their intensities were impacted by doping content, reaching the maximum value when the Sm 3+ content was 1 mol% and the involved concentration mechanism was dominated by quadrupole–quadrupole interaction. Through analyzing the degradation of TC, the visible light triggered photocatalytic behaviors of the resultant compounds were studied. Compared with BiOCl microplates, an improved TC removal ability was seen in Sm 3+ -doped BiOCl microplates and the products with a Sm 3+ content of 0.5 mol% show the best performance. Moreover, through constructing the heterojunction with g-C 3 N 4 , the TC removal capacity was further enhanced and the BiOCl:Sm 3+ @60%g-C 3 N 4 exhibits the optimal photocatalytic activity, which was also much better than that of the commercial SnO 2 and TiO 2 . Accordingly, the ˙O 2 − , h + and ˙OH active species were proven to contribute to the involved visible light driven photocatalytic mechanism. Furthermore, the separation and recombination of photogenerated carries via the Z-scheme transfer process in the designed heterojunction composites, led to splendid photocatalytic properties. Additionally, it was verified that the TC solution treated with synthesized compounds was nontoxic toward plant growth. Our findings may propose an available route to regulate the photocatalytic performance of the visible light driven photocatalysts.
Locoregional spread of abdominopelvic malignant tumors frequently results in peritoneal carcinomatosis(PC). The prognosis of PC patients treated by conventional systemic chemotherapy is poor, with a ...median survival of < 6 mo. However, over the past three decades, an integrated treatment strategy of cytoreductive surgery(CRS) + hyperthermic intraperitoneal chemotherapy(HIPEC) has been developed by the pioneering oncologists, with proved efficacy and safety in selected patients. Supported by several lines of clinical evidence from phases Ⅰ, Ⅱ and Ⅲ clinical trials, CRS + HIPEC has been regarded as the standard treatment for selected patients with PC in many established cancer centers worldwide. In China, an expert consensus on CRS + HIPEC has been reached by the leading surgical and medical oncologists, under the framework of the China Anti-Cancer Association. This expert consensus has summarized the progress in PC clinical studies and systematically evaluated the CRS + HIPEC procedures in China as well as across the world, so as to lay the foundation for formulating PC treatment guidelines specific to the national conditions of China.
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