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The oxygen evolution reaction (OER) is a pivotal process in water electrolysis systems, yet developing cost-effective and highly active OER electrocatalysts from earth-abundant materials through straightforward methods remains a formidable challenge. In this study, FeCo oxides and their fluorides are synthesized using a one-step room-temperature process followed by fluorination with fluorine gas. We compared the OER performance of Fe, Co, and FeCo oxides and investigated the impact of fluorine doping on their physical properties and OER efficiency. Results revealed that the FeCo–O bimetallic oxide exhibited an overpotential of 370 mV in an alkaline electrolyte at a current density of 10 mA/cm2, significantly surpassing the performance of monometallic Fe–O (1 V) and Co–O (467 mV). Fluorine modification markedly enhanced the OER activity of these materials, with Fe-OF at 570 mV, Co-OF at 330 mV, and FeCo-OF at 285 mV. Notably, FeCo-OF demonstrated a stable overpotential lower than commercial RuO 2 (289 mV) during a continuous 12 h OER test. Electrochemical analyses and spectral characterizations indicated that fluorine ion electronic regulation facilitated efficient electrocatalytic active sites in the spent FeCo-OF catalyst through in situ self-reconstruction, leading to its stable and superior OER performance. Density functional theory (DFT) calculations confirmed that fluorine modification of the bimetallic oxides decreased the O* Gibbs free energy from 4.86 to 2.44 eV, thereby enhancing the kinetics of the OER reaction. Prepared metal oxides (Fe–O, Co–O, FeCo–O), fluorine-doped metal oxides (Fe-OF, Co-OF, FeCo-OF), and fluorine-decorated FeCo bimetallic oxides (FeCo-OF) exhibit excellent OER performance (η 10 = 285 mV). DFT calculations suggest that fluorine decoration reduces the Gibbs free energies of O⁎ adsorption (Δ G O⁎) and enhances OER reaction kinetics under alkaline conditions. [Display omitted] • Fluorine decoration enhances OER performance in Fe, Co, and FeCo catalysts. • Electronic regulation of fluoride facilitates FeCo-OF surface self-reconstruction. • FeCo-OF exhibits excellent OER performance (η 10 = 285 mV). • Fluorine decoration reduces O* Gibbs free energy and promote OER reaction kinetics. [ABSTRACT FROM AUTHOR]

The metal-oxide interaction has been considered as an effective factor for catalytic performance in methanol steam reforming. In this work, Ti modified Cu/γ-Al 2 O 3 /Al catalyst was prepared by anodization technology. It is found that the addition of Ti can largely increase the surface area of the carrier and thus improve the dispersion of copper. The co-existence of Ti4+ and Ti3+ makes the charge transfer between Cu and Ti easier, which improves the redox performance of copper. The DFT calculations reveal that Ti also enhance the adsorption capacity of water and methanol on the surface of the catalysts. Besides, Ti also reduce the acid density on the carrier, inhibit methanol dehydration reaction and thereby reduce the selectivity of the DME. The optimal catalyst CuTi 1.9 /γ-Al 2 O 3 /Al achieves nearly 100% conversion at 275 °C, while the methanol conversion of Cu/γ-Al 2 O 3 /Al is 82%. And the H 2 output of CuTi 1.9 /γ-Al 2 O 3 /Al reached 69.17 mol/(kg cat ·h) at 300 °C. • Ti modified Cu/γ-Al2O3/Al catalysts improve the high-purity hydrogen production. • Strong electronic interaction was found between Cu and Ti. • The addition of Ti enhances the adsorption capacity of water and methanol molecule. • The introduction Ti reduces the acid density on the surface of the carrier. [ABSTRACT FROM AUTHOR]

Nowadays, MnO 2 -based catalysts have been widely applied in environmental fields, especially the removal of HCHO at room temperature. However, the moisture resistance of the catalyst is still a challenge. In this study, a series of MnTi x /γ-Al 2 O 3 /Al catalysts were prepared by the methods of redox precipitation and impregnation, which showed excellent HCHO removal efficiency under humid conditions. When the catalyst accumulatively treated ca. 25 ppm of HCHO, there was still a HCHO conversion of 87.5% and the activity can be restored by washing and drying. DFT calculations, XPS, and TG results showed that Ti-modification could inhibit the adsorption of physisorbed water on the catalyst surface, thereby weakening the competitive adsorption between H 2 O and HCHO. This study provides a feasible strategy for the removal of HCHO under humid conditions. [Display omitted] • Ti-modified Mn/γ-Al 2 O 3 /Al was developed for HCHO removal. • The activities for HCHO (ca. 0.9 ppm) under different RH conditions were evaluated in the 3 m3 air cabin. • Ti-modification inhibited the adsorption of H 2 O on the catalyst. • The MnTi 1.9 /γ-Al 2 O 3 /Al catalyst showed excellent HCHO removal efficiency under humid conditions. • The flexible mesh-type catalyst has broad prospects for practical application in indoor purification. [ABSTRACT FROM AUTHOR]