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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]

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]