The application of solid polymer electrolytes (SPEs) in all-solid-state(ASS) batteries is hindered by lower Li + -conductivity and narrower electrochemical window. Here, three families of ester-based F-modified SPEs o...
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The application of solid polymer electrolytes (SPEs) in all-solid-state(ASS) batteries is hindered by lower Li + -conductivity and narrower electrochemical window. Here, three families of ester-based F-modified SPEs of poly-carbonate (PCE), poly-oxalate (POE) and poly-malonate (PME) were investigated. The Li + -conductivity of these SPEs prepared from pentanediol are all higher than the counterparts made of butanediol, owing to the enhanced asymmetry and flexibility. Because of stronger chelating coordination with Li + , the Li + -conductivity of PME and POE is around 10 and 5 times of PCE. The trifluoroacetyl-units are observed more effective than −O−CH 2 −CF 2 −CF 2 −CH 2 −O− during the in situ passivation of Li-metal. Using trifluoroacetyl terminated POE and PCE as SPE, the interfaces with Li-metal and high-voltage-cathode are stabilized simultaneously, endowing stable cycling of ASS Li/LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) cells. Owing to an enol isomerization of malonate, the cycling stability of Li/PME/NCM622 is deteriorated, which is recovered with the introduce of dimethyl-group in malonate and the suppression of enol isomerization. The coordinating capability with Li + , molecular asymmetry and existing modes of elemental F, are all critical for the molecular design of SPEs.
Minimizing surface defect is vital to further improve power conversion efficiency (PCE) and stability of inorganic perovskite solar cells (PSCs). Herein, we designed a passivator trifluoroacetamidine (TFA) to suppress...
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Minimizing surface defect is vital to further improve power conversion efficiency (PCE) and stability of inorganic perovskite solar cells (PSCs). Herein, we designed a passivator trifluoroacetamidine (TFA) to suppress CsPbI 3− x Br x film defects. The amidine group of TFA can strongly chelate onto the perovskite surface to suppress the iodide vacancy, strengthened by additional hydrogen bonds. Moreover, three fluorine atoms allow strong intermolecular connection via intermolecular hydrogen bonds, thus constructing a robust shield against moisture. The TFA-treated PSCs exhibit remarkably suppressed recombination, yielding the record PCEs of 21.35 % and 17.21 % for 0.09 cm 2 and 1.0 cm 2 device areas, both of which are the highest for all-inorganic PSCs so far. The device also achieves a PCE of 39.78 % under indoor illumination, the highest for all-inorganic indoor photovoltaic devices. Furthermore, TFA greatly improves device ambient stability by preserving 93 % of the initial PCE after 960 h.
It is vitally important to develop highly active, robust and low-cost transition metal-based electrocatalysts for overall water splitting in neutral solution especially at large current density. In this work, amorphou...
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It is vitally important to develop highly active, robust and low-cost transition metal-based electrocatalysts for overall water splitting in neutral solution especially at large current density. In this work, amorphous Mo-doped NiS 0.5 Se 0.5 nanosheets@crystalline NiS 0.5 Se 0.5 nanorods (Am−Mo−NiS 0.5 Se 0.5 ) was synthesized using a facil one-step strategy. In phosphate buffer saline solution, the Am−Mo−NiS 0.5 Se 0.5 shows tiny overpotentials of 48 and 209 mV for hydrogen evolution reaction (HER), 238 and 514 mV for oxygen evolution reaction (OER) at 10 and 1000 mA cm −2 , respectively. Moreover, Am−Mo−NiS 0.5 Se 0.5 delivers excellent stability for at least 300 h without obvious degradation. Theoretical calculations revealed that the Ni sites in the defect-rich amorphous structure of Am−Mo−NiS 0.5 Se 0.5 owns higher electron state density and strengthened the binding energy of H 2 O, which will optimize H adsorption/desorption energy barriers and reduce the adsorption energy of OER determining step.
In this article, a tamarind seed gum-g-poly (acrylic acid-co-2-Acrylamido-2-methyl-1-propane sulfonic acid/polyvinyl alcohol) (TSG-g-P[AA-co-AMPS/PVA]) was prepared by aqueous solution polymerization. The Fourier tran...
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In this article, a tamarind seed gum-g-poly (acrylic acid-co-2-Acrylamido-2-methyl-1-propane sulfonic acid/polyvinyl alcohol) (TSG-g-P[AA-co-AMPS/PVA]) was prepared by aqueous solution polymerization. The Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis were used to characterize. The swelling behaviors, reusability and water-retention capabilities of hydrogels were evaluated. Under optimum synthesis conditions, the maximum equilibrium absorption of hydrogel was 1295 g·g −1 , 208 g·g −1 , 116 g·g −1 in deionized water, tap water and NaCl solution (0.9 wt%) respectively. Application of the hydrogel to soils increased their water-holding and fertilizer retention capacities. Furthermore, the excellent water retention anti-evaporation performance indicated that the hydrogel has the potential for applications in future sustainable agriculture and forestry.
A highly enantioselective catalytic system for exo -Diels–Alder reactions was developed based on the newly discovered bispyrrolidine diboronates (BPDB). Activated by various Lewis or Brønsted acids, BPDB can cat...
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A highly enantioselective catalytic system for exo -Diels–Alder reactions was developed based on the newly discovered bispyrrolidine diboronates (BPDB). Activated by various Lewis or Brønsted acids, BPDB can catalyze highly stereoselective asymmetric exo -Diels–Alder reactions of monocarbonyl-based dienophiles. When 1,2-dicarbonyl-based dienophiles are used, the catalyst can sterically distinguish between the two binding sites, which leads to highly regioselective asymmetric Diels–Alder reactions. BPDB can be prepared as crystalline solids on a large scale and are stable under ambient condition. Single-crystal X-ray analysis of the structure for acid-activated BPDB indicated that its activation involves cleavage of a labile B←N bond.
Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) is a pair of microsatellites (i.e. GECAM-A and GECAM-B) dedicated to monitoring gamma-ray transients including gravitational waves hig...
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Given health threat by global warming and increased energy consumption in regulating body temperature, it is an urgent need to construct smart temperature-regulating materials. Herein, a novel fiber-spinning asymmetri...
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Given health threat by global warming and increased energy consumption in regulating body temperature, it is an urgent need to construct smart temperature-regulating materials. Herein, a novel fiber-spinning asymmetric chemical assembly (FACA) method is proposed to construct nanofiber materials with asymmetric photothermal properties. The silver nanowires (AgNWs) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) with opposite thermal radiation are assembled on reduced graphene oxide (rGO) film, imparting AgNW/rGO/PVDF-HFP film with Janus structure that can realize the AgNWs side consistently keeps temperature of ca. 11 °C lower than the side of PVDF-HFP nanofiber regardless of the irradiation directions under 1 sun, suggesting the adjustable photothermal regulation. Such photothermally selective hybrid nanofiber film provides great potential as fabrics to achieve all-weather smart clothes, promoting controllable and comprehensive utilization of solar energy.
Two-dimensional (2D) AIE-inorganic nanocomposites exhibit high stability and high fluorescence activity. However, limited by the types and properties of 2D inorganic materials, it's challenging to realize complex ...
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Two-dimensional (2D) AIE-inorganic nanocomposites exhibit high stability and high fluorescence activity. However, limited by the types and properties of 2D inorganic materials, it's challenging to realize complex structures and functions. We designed a quaternary ammonium-type AIE ligand, TPECholine. We chose TPECholine and POM clusters as building blocks and synthesized a series of single-layer nanosheets (SLNSs) by assembling LnW 10 or P 2 W 18 POM clusters with TPECholine. By regulating the types of POM clusters and ligands, the morphology and fluorescence intensity of the SLNSs can be finely tuned. Due to the restriction of the intramolecular motions of AIEgens by the SLNSs, nanosheets can exhibit promoted quantum yield (up to 76 %). In addition, thanks to the sub-nanometric sizes and excess surface charges, SLNSs exhibit excellent solvent compatibility, including water, chloroform, ethanol, etc. And the nanosheets showed high fluorescence intensity in these solvents.
Room-temperature phosphorescent (RTP) materials have great potential for in vivo imaging because they can circumvent the autofluorescence of biological tissues. In this study, a class of organic-doped long-wavelength ...
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Room-temperature phosphorescent (RTP) materials have great potential for in vivo imaging because they can circumvent the autofluorescence of biological tissues. In this study, a class of organic-doped long-wavelength (≈600 nm) RTP materials with benzo[c][1,2,5] thiadiazole as a guest was constructed. Both host and guest molecules have simple structures and can be directly purchased commercially at a low cost. Owing to the long phosphorescence wavelength of the doping system, it exhibited good tissue penetration (10 mm). Notably, these RTP nanoparticles were successfully used to image atherosclerotic plaques, with a signal-to-background ratio (SBR) of 44.52. This study provides a new approach for constructing inexpensive red organic phosphorescent materials and a new method for imaging cardiovascular diseases using these materials.
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