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Organic alloy solid electrolytes were prepared based on succinonitrile-neopentylglycol (SCN-NPG) eutectics for Dye-sensitized solar cells (DSSCs). The solid-state electrolytes with the SCN:NPG ratios of 40:60 to 20:80 mol% exhibited a very high conductivity of >2.0 mS cm −1 at room temperature. The DSSC cell with the organic alloy electrolyte showed highest photoconversion efficiency of 4.4% at 100 mW cm −2 and a long-term stability as compared with organic liquid or melted plastic electrolytes, offering a low cost, thermostable solid-state electrolyte for commercial development of high efficient dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd/WO 3 was designed for catalyzing the reduction of toxic pollutants. • DFT and XPS unravel a unique catalytic mechanism for the Cr(VI) reduction by formic acid. • Electron transfer at WO 3 /Pd interfaces optimizes Pd electronic states and upshifts d -band center. • Electron-deficient Pd boosts formic acid dissociation for efficient H* production. • Pd/WO 3 surpasses most Pd-based catalysts for Cr(VI) reduction with high TOF of 62.12 min−1. Through theoretical calculations, we show that integrating Pd with WO 3 nanomaterials can trigger the interfacial electron transfer from Pd to WO 3 , thus upshifting the d -band center (ε d) of Pd to optimize toxic hexavalent chromium (Cr(VI)) reduction. The elevated ε d can derive stronger chemisorption capability toward crucial formic acid molecules, notably lowering the thermodynamic energy barrier and speeding up the kinetics process. In order to realize this concept, we synthesized unique Pd/WO 3 nanofibers by loading Pd nanoparticles onto electrospun WO 3 nanofibers through an in situ photodeposition technique. Extensive structural, morphological, and X-ray photoelectron spectrometer (XPS) characterizations confirm the successful formation of the above nanofibers. As anticipated, the as-designed Pd/WO 3 nanofibers exhibit enhanced catalytic performance in the Cr(VI) reduction with a high turnover frequency (TOF) value of 62.12 min−1, surpassing a series of reported Pd-based catalysts. Such nanofibrous WO 3 -induced electronic modification of Pd with a high specific area leads to catalytic enhancement, providing a novel model for catalyst design. [ABSTRACT FROM AUTHOR]

Photocatalytic oxidation technology can mineralize hazardous volatile organic compounds (VOCs), but the poor photocatalytic oxidation activity limits its practical application. Here we develop Cu‐doped WO3 electrospun nanofibers through a non‐equivalent doping strategy. The Cu dopant prefers substituting five‐coordinated W atoms atop the WO3 matrix, inducing strong dopant/matrix interaction (SDMI) effect and prominent charge rearrangement. A localized electric field (LEF) forms pointing from positively charged WO3 matrix to negatively charged Cu dopant, which triggers efficient photoexcited charge separation. Further, the Cu dopant promoted the production of ⋅OH radicals and thereby enhanced VOCs photodegradation. The 0.7 % Cu‐doped WO3 nanofibers show optimal photocatalytic oxidation performance towards formaldehyde and acetone, 5.5 and 4.8 times higher than pristine WO3 nanofibers, respectively. This work highlights the role of dopant‐induced LEF on the charge carriers separation and might shed light on developing more efficient photocatalysts with non‐equivalent dopants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ti 3 C 2 /Pd was designed for efficient catalytic transfer hydrogenation of nitrobenzene. • Experimental and DFT theoretical studies unravel unique catalytic mechanism. • Electron transfer at Ti 3 C 2 /Pd interfaces changes Pd electron configure (4 d 10 → 4 d 10-x). • Electron-deficient Pd boosts formic acid dissociation for atomic H* production. • Ti 3 C 2 /Pd chemisorbs active H* and inhibits undesirable H 2 evolution. Catalytic transfer hydrogenation (CTH) with formic acid attracts much interest in catalysis, but the sluggish H* production and undesirable H 2 evolution reaction (HER) limit its practical applications. Herein we anchored Pd nanoparticles (NPs) on layered Ti 3 C 2 MXene for efficient and selective CTH of nitrobenzene in the presence of formic acid. Some electrons in Pd NPs transferred to Ti 3 C 2 MXene upon formation of Ti 3 C 2 /Pd nanohybrids, as confirmed by XPS and DFT simulations. The electron transfer changed Pd valance electron configuration from 4 d 10 to 4 d 10-x. Such electron-deficient Pd NPs tuned reaction pathway and promoted formic acid dissociation, both of which favored the production of active H* atoms, i.e., the exact reductant for CTH. Compared with Pd NPs, Ti 3 C 2 /Pd showed stronger adsorption of H* and therefore inhibited the occurrence of HER (2H*→H 2). Owing to favorable H* production and HER inhibition, Ti 3 C 2 /Pd (15 wt% Pd) showed enhanced nitrobenzene CTH performance with turnover frequency of 351.7 h−1 and 99% aniline selectivity, outperforming most of current catalysts. Our work might inspire designing more advanced CTH catalysts by tuning their valance electron configurations with 2D MXene materials. [ABSTRACT FROM AUTHOR]

Chitosan-based carbon materials have attracted great attention in electrochemical energy storage. Introducing iron metal or iron compounds into carbon materials favors to boost their electrochemical performance. Herein, chitosan-based graphitic carbon@Fe3C composites (CSGC@Fe3C) have been prepared as anode materials for lithium ion battery by a simple pyrolysis method. By manipulating the temperature higher than 700 °C, pure Fe3C encapsulated in chitosan-based graphitic carbon with different mass ratio from 30 to 53.8 wt% can be achieved. The resulting CSGC@Fe3C composites retain porous carbon sheet structure embedded with a large amount of Fe3C nanoparticles in size from 20 to 300 nm. The electrochemical measurements demonstrate CSGC@Fe3C with 53.8 wt% Fe3C as anode material for lithium ion battery can provide a highest reversible capacity of 423 mAh g−1 at 0.1 A g−1 over 100 charge/discharge cycles and stable cycling capacity of 195 mAh g−1 at a high current density of 2 A g−1 during 200 cycles. The catalysis of Fe3C on the reversible formation and decomposition of solid electrolyte interphase (SEI) has been corroborated and results in the improvement of surface capacitive contribution. This work provides a basic insight into metal carbides constructing biomass-based carbon anode materials to realize high-performance electrochemical energy storage device. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electron rearrangement occurs around Co dopant owing to the strong dopant/matrix interaction. • Localized electric field is present with direction pointing from Co dopant to WO 3 matrix. • Efficient charge separation and transfer are achieved owing to the LEF. • Co dopants activate oxygen with favorable production of O 2 – radicals for VOCs oxidation. Exploring efficient photocatalysts for degrading hazardous volatile organic compounds (VOCs) is gaining increasing popularity. Herein, we developed Co-doped WO 3 nanofibrous photocatalysts by incorporating Co dopant into the WO 3 lattice, where hexavalent W(VI) is replaced with divalent Co(II). This heterovalent substitution causes significant charge rearrangement around the Co dopant, resulting in a localized electric field (LEF) that enhances oxygen adsorption and activation. Such an electric field drives photoexcited electrons to gather at the Co dopant, thereby achieving spatial charge separation. Both the efficient oxygen activation and LEF forming contribute to the production of superoxide radicals. The Co0.8-WO 3 nanofibers demonstrated improved photocatalytic oxidation of gaseous HCHO and CH 3 COCH 3 compared to WO 3. This study highlights the significant promotion of dopant-induced oxygen adsorption and LEF-induced efficient carrier separation. These findings offer a new direction for developing more efficient photocatalysts using unique doping approaches. [ABSTRACT FROM AUTHOR]

Conversion of biomass waste into nitrogen‐doped porous carbon has been considered as a promising approach to achieve energy storage materials. Nitrogen‐doped activated carbon materials have been successfully prepared by molten salt pyrolysis (MSP) using melamine modified‐denim fabric waste as precursor. The molten salt medium provides liquid condition to carbonize and activate the denim fabric waste. Melamine produces a large amount of nitrogen element for doping the carbon materials. The obtained nitrogen‐doped denim fabric‐based carbon materials (NDFC‐MSP) are composed of small fibrous fragment and thin sheet, and exhibit a high specific surface area (1975.2 m2⋅g−1) and high pore volume (1.087 cm3⋅g−1). Moreover, NDFC‐MSP sample with a high nitrogen content of 6.93 wt.% possesses a maximum specific capacitance of 345.8 F⋅g−1 at 0.25 A⋅g−1 in 6 M KOH electrolyte. It also displays a high specific capacitance of 230 F⋅g−1 at 10 A⋅g−1. The cycle stability shows 95.5% retention after 5000 charge‐discharge cycles at 1 A⋅g−1. In addition, the fabricated symmetric NDFC‐MSP supercapacitor with a wide voltage range of 1.8 V generates a maximum energy density of 17.0 Wh⋅kg−1 at power density of 225 W kg−1 in 1 M Na2SO4 aqueous electrolyte. [ABSTRACT FROM AUTHOR]