Manganese dioxide (MnO2), with naturally abundant crystal phases, is one of the most active candidates for toluene degradation. However, it remains ambiguous and controversial of the phase–activity relationship and the origin of the catalytic activity of these multiphase MnO2. In this study, six types of MnO2 with crystal phases corresponding to α‐, β‐, γ‐, ε‐, λ‐, and δ‐MnO2 are prepared, and their catalytic activity toward ozone‐assisted catalytic oxidation of toluene at room temperature are studied, which follow the order of δ‐MnO2 > α‐MnO2 > ε‐MnO2 > γ‐MnO2 > λ‐MnO2 > β‐MnO2. Further investigation of the specific oxygen species with the toluene oxidation activity indicates that high catalytic activity of MnO2 is originated from the rich oxygen vacancy and the strong mobility of oxygen species. This work illustrates the important role of crystal phase in determining the oxygen vacancies’ density and the mobility of oxygen species, thus influencing the catalytic activity of MnO2 catalysts, which sheds light on strategies of rational design and synthesis of multiphase MnO2 catalysts for volatile organic pollutants’ (VOCs) degradation.

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Deficiencies in understanding the local environment of active sites and limited synthetic skills challenge the delivery of industrially‐relevant current densities with low overpotentials and high selectivity for CO2 reduction. Here, a transient laser induction of metal salts can stimulate extreme conditions and rapid kinetics to produce defect‐rich indium nanoparticles (L‐In) is reported. Atomic‐resolution microscopy and X‐ray absorption disclose the highly defective and undercoordinated local environment in L‐In. In a flow cell, L‐In shows a very small onset overpotential of ≈92 mV and delivers a current density of ≈360 mA cm‐2 with a formate Faradaic efficiency of 98% at a low potential of −0.62 V versus RHE. The formation rate of formate reaches up to 6364.4 µmol h‐1 mgIn–1$mg_{{\rm{In}}}^{--1}$, which is nearly 39 folds higher than that of commercial In (160.7 µmol h‐1 mgIn–1$mg_{{\rm{In}}}^{--1}$), outperforming most of the previous results that have been reported under KHCO3 environments. Density function theory calculations suggest that the defects facilitate the formation of *OCHO intermediate and stabilize the *HCOOH while inhibiting hydrogen adsorption. This study suggests that transient solid‐state laser induction provides a facile and cost‐effective approach to form ligand‐free and defect‐rich materials with tailored activities.

Fabricating heterostructures with dense interfacial catalytic sites is vitally essential for implementation of high-performance hydrogen evolution reaction (HER). However, the strong correlation between the adsorbed hydrogen atoms and electronegative nonmetal...

Carbon dioxide (CO2) reduction to value-added fuels and chemicals by making full use of the electricity generated from clean energy is promising to address environmental pollution and the energy crisis....

Molybdenum sulfide (MoS2) has extensively attracted attention as a promising nonprecious metal catalyst for the electrochemical hydrogen evolution reaction (HER). Nevertheless, synergistically enhancing the intrinsic conductivity and active sites of MoS2 is the pivotal challenge to build up its hydrogen production performance. Herein, a facile ionic liquid-assisted hydrothermal and subsequent annealing treatment strategy is first reported to synthesize W-doped MoS2 nanosheets supported on carbon cloth (Mo1‑x W x S y /CC). The experimental results prove that the substitutional W doping can effectively activate the catalytic activity of the inert basal plane of MoS2 due to the generation of sulfur vacancies. Density functional theory calculations further confirm that W doping and S vacancies reduce the band gap of MoS2 and promote the adsorption of H atoms, thereby greatly improving the HER performance. The synergistic effects of W doping and S vacancies endow this material remarkable HER performance with a low Tafel slope of 49.3 mV dec–1 and an overpotenial of 165 mV for 10 mA cm–2 in 0.5 M H2SO4 solution. In short, our new strategy provides a simple and efficient pathway to synthesize Mo1‑x W x S y /CC, and it can be applied to the design of other materials possessing multifarious merits.

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