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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]

[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]

[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]