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In situstudies of the relationship between surface spin configurations and spin-related electrocatalytic reactions are crucial for understanding how magnetic catalysts enhance oxygen evolution reaction (OER) performance under magnetic fields. In this work, 2D Fe7Se8nanosheets with rich surface spin configurations are synthesized via chemical vapor deposition. In situmagnetic force microscopy and Raman spectroscopy reveal that a 200 mT magnetic field eliminates spin-disordered domain walls, forming a spin-ordered single-domain structure, which lowers the OER energy barrier, as confirmed by theoretical calculations. Electrochemical tests show that under a 200 mT magnetic field, the OER overpotential of multidomain Fe7Se8nanosheets at 10 mA cm–2decreases from 346 mV to 259 mV, while the magnetic field has minimal effect on single-domain nanosheets. These findings highlight the critical role of spin configurations in enhancing electrocatalytic performance, offering new insights into the design of magnetic catalysts for industrial applications.

Selective catalytic reduction of NO by CH4(CH4-SCR) is a promising choice to eliminate toxic NO from emissions of mobile and stationary sources. However, because of insufficient activity, so far a catalyst for CH4-SCR has not been used commercially. Getting a clear understanding of the mechanism of CH4-SCR is thus very important for developing an optimum catalyst for the NO elimination. From the angle of multifunctional catalysis, we designed a catalyst which consisted of CoOxand Ce/HZSM-5. With the synergistic function of the catalysis, the activity of CH4-SCR was considerably enhanced. In situ diffuse reflectance infrared Fourier transform spectroscopy was applied to investigate the catalytic mechanism of CH4-SCR. It suggests that CoOxoffers the sites to boost the oxidation of NO to NOx. Meanwhile, Ce/HZSM-5 provides redox and acidic sites which are necessary for activating methane and reducing the formed intermediates into desired products, N2and CO2.

A Pt-Rh three-way catalyst (M-DS) supported on CeO2-ZrO2-La2O3-Nd2O3and its analogous supported catalyst (DS) were developed via a modified double-solvent method and conventional double-solvent method, respectively. The as-prepared catalysts were characterized by N2adsorption-desorption, X-ray diffraction (XRD), CO-chemisorption, X-ray photoelectron spectroscopy (XPS) and hydrogen temperature-programmed reduction (H2-TPR). The preformed Pt nanoparticles generated using ethanol as a reducing agent on M-DS presented enhanced Pt dispersion regardless of aging treatment as confirmed by XRD and CO-chemisorption measurements. The textural properties and reduction ability of M-DS were maintained to a large extent after aging treatment. This result was consistent with those of the N2adsorption-desorption and H2-TPR, respectively. Meanwhile, the XPS analysis demonstrated that higher Pt0species and larger Ce3+concentration could be obtained for M-DS. In the conversion of a simulated compressed natural gas (CNG) vehicle exhaust, both fresh and aged M-DS showed a significant enhancement in the activity and N2-selectivity. Particularly, the complete conversion temperature (T90) of CH4over the aged M-DS catalyst was 65 °C lower than that over the aged catalyst by conventional double-solvent method.