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This article explores a supported catalyst of Fe(bpy)32+ on a cationic exchange resin (Amberlite IRA 200) as a photocatalyst for the degradation of organic pollutants by activating molecular oxygen under visible irradiation (λ>420 nm) in water. Different from Fe(bpy)32+ which is not photoactive in solution, the supported catalyst exhibits a very efficient photoactivity for the degradation of N,N-dimethylaniline and the cationic dyes of Rhodamine B (RhB) and Malachite Green (MG) in an aerated aqueous medium. TOC removal yield was 75, 60 and 58%, respectively, after 700 min of visible light irradiation. The photocatalytic activity of the supported Fe(bpy)32+ remained unchanged after 22 cycles of over 100 h. The photocatalyst was characterized by UV-Vis diffuse reflectance, and X-ray photoelectron spectroscopies (XPS). EPR studies suggest that the active superoxide species {Fe(bpy)33+O2⋅−} are involved in the light-activated reaction. A reaction mechanism is proposed in the text. [Copyright &y& Elsevier]

Ru-modified monolayer-dispersed WO x /CeO 2 hybrid composites were prepared by co-impregnation (CI) and step impregnation (SI) methods, and the effects of active site distribution on the catalytic oxidation of 1,2-dichloroethane (DCE) were investigated. Ru species tends to be deposited on the monolayer-dispersed WO x (m-WO x) by SI method, which can increase the oxygen vacancies (O V,m-WOx) at m-WO x /CeO 2 interfaces. Abundant O V,m-WOx can promote the formation of more active W–OH and accelerate the dechloridation and oxydehydrogenation of DCE. Oppositely, for CI method, Ru species exists mainly in the form of Ru−O−Ce bonds, increasing the oxygen vacancies (O V,RuCe) into CeO 2 surface lattices and promoting the deep oxidation of intermediate products. The closer contact between the two hetero-interfacial oxygen vacancies (O V,RuCe and O V,m-WOx) on Ru-modified m-WO x /CeO 2 produces a stronger synergistic effect on DCE activation and oxidation, and meanwhile advantageously inhibits the adsorption of chlorine species as well as the formation of polychlorinated by-products. [Display omitted] • Impregnation sequence affects active site distribution on Ru-modified m-WO x /CeO 2 catalysts. • Ru species on m-WO x surfaces increases O V,m-WOx and W–OH by SI method. • CI method generates more Ru−O−Ce and O V,RuCe. • Synergies of hetero-interfacial O V promote DCE activation/oxidation and inhibit Cl species absorption. [ABSTRACT FROM AUTHOR]

The direct methane (CH 4) oxidation to high value-added C1 chemicals is a great promising strategy to explore the CH 4 resource utilization. However, the low activity and selectivity of catalytic performance remains a great conundrum due to the difficulty to activate the C H bond and the unmanageable over oxidation. Herein, Pd x Au y nanowires (NWs) with various Pd/Au atomic ratios are presented as ideal models to explore the atomic-level effect of PdAu atoms for the direct CH 4 oxidation. The influence of reaction parameters are systematically investigated, and Pd 9 Au 1 NWs display a maximum yield of 2890.3 μmol g−1 h−1 with 99% selectivity for the liquid C1 oxygenated products. This enhanced performance is attributed to the combination of one-dimensional structure and the synergistic effect from the suitable portion of Au on Pd sites, which regulates bond strength between adsorbed radicals (•OH, •OOH, •CH 3) and PdAu atoms, confirmed by the density function theory calculations. [Display omitted] • High quality Pd x Au y NWs with different Pd/Au atomic ratios are prepared by galvanic replacement reaction. • The Pd 9 Au 1 NWs show a maximum yield of 2890.3 μmol g-1 h-1 and a 99% selectivity for liquid C1 products. • The incorporation of Au moderates binding strength of intermediates, facilitating the C-H activation. [ABSTRACT FROM AUTHOR]

Integrating high-efficiency oxygen evolution catalysts from the waste printed circuit board leachates is achieved via a one-step boriding recycling strategy. [Display omitted] • Mixed metal borides (FeNiCuSnBs) were obtained from waste printed circuit boards via a facile boriding process. • High metal ion recovery rates (over 99.40 %) are achieved for Fe, Ni, Cu and Sn via the boriding process. • The optimal metal boride exhibits a record‐high activity (η 10 = 199 mV) among waste-derived OER electrocatalysts. • The metal borides features accelerated surface self-reconstruction via B and Sn co-etching under OER conditions. • The in-situ generated metal (oxy)hydroxides act as the catalytic active sites. Converting electronic wastes into high-efficiency energy conversion catalysts is a win-win strategy in addressing the metal resources shortage and sustainable energy challenges. Herein, a facile boriding strategy is developed to directly convert the leachates of waste printed circuit boards into magnetic mixed metal borides (FeNiCuSnBs) for oxygen evolution reaction (OER) catalysts. Via the boriding process, a metal cation recovery rate of 99.78 %, 99.98 %, 99.96 %, and 99.49 % has been attained for Fe, Ni, Cu, and Sn, respectively. The obtained catalysts with a higher ratio of Ni and Fe show better OER performance. The optimal FNCSB-4 attains 10 mA cm−2 at a low overpotential of 199 mV, as well as good stability in alkaline solution. Remarkably, FNCSB-4 represents a record‐high activity among waste-derived OER electrocatalysts. In-depth study suggests that the superior OER performance is mainly owing to accelerated surface self-reconstruction by B/Sn co-etching under OER potential region, and the newly formed multimetal (oxy)hydroxides act as the active species for OER. Additionally, the efficient mass/charge transfer, the amorphous feature, and hierarchical structure also benefit OER. Apart from providing an insight into the correlation between surface self-reconstruction and OER activity of multimetal boride-based catalysts, this study also offers a general strategy for the high-efficiency recovery and advanced energy-driven applications of critical metals from other urban mines in a sustainable and environment-friendly approach. [ABSTRACT FROM AUTHOR]

• Cross-linked multi-atom Pt anchored on a Zn, Fe and N co-doped carbon catalyst is prepared. • The MAC-Pt/ZnFe -N- C catalyst shows 100 % exposure of surface Pt atoms. • The MAC-Pt/ZnFe -N- C catalyst exhibits remarkable catalytic activity and stability for the oxygen reduction reaction. • A fuel cell assembled by this catalyst delivers a maximal power output of 1.02 W cm−2 at 0.035 mg Pt cm−2 at the cathode. Although single-atom catalysts (SACs) are drawing wide attention because they offer properties that differ from those of conventional nanoparticle (NP)-based catalysts, the lack of neighboring metal centers to cooperate in catalysis limits their actual application in many important chemical processes. Here, we report the synthesis of multi-atom Pt catalyst that consists of cross-linked Pt-Pt metal centers stabilized by atomically dispersed ZnFe -N- C support through Pt-N bonds. XAFS analysis reveals that each Pt atom in the multi-atom Pt catalyst coordinates with ∼2.6 N atoms and ∼4.3 Pt atoms. This novel catalyst combines the merits of SACs and NPs, resulting in 100 % exposure of surface Pt atoms and excellent stability and fuel cell performance. With an ultralow Pt loading of 0.035 mg cm−2 at the cathode, the fuel cell delivers a 1.02 W cm-2 maximal power output. DFT calculations revealed that the strongly coupled Pt-N bond is critical for stabilizing the cross-linked Pt. [ABSTRACT FROM AUTHOR]

• Preparing catalyst with a novel unsaturated-impregnation-precipitation method. • uip-γ-Al 2 O 3 -CeO 2 -500 °C continuously get 97 % yield of imine in a fixed bed reactor. • The isolated yield of imine and TON BA reached up to 81 % and 16838 after 20 days. • uip-γ-Al 2 O 3 -CeO 2 -500 °C could be reactivated in situ in the fixed reactor. • Abundant acid sites of γ-Al 2 O 3 and the synergistic effect between CeO 2 and γ-Al 2 O 3. One-pot synthesis of imines from benzyl alcohols and anilines by heterogeneous catalysis in batch reactor has already been widely studied, but its high cost and low production efficiency limit its application in the fine chemicals industry. In this work, γ-Al 2 O 3 balls supported CeO 2 catalyst (uip-γ-Al 2 O 3 -CeO 2) was prepared by a novel unsaturated-impregnation-precipitation method, and was employed as a catalyst for continuous solvent-free synthesis of imines in a fixed bed reactor. Under the optimal technological parameter of fixed bed reactor and reaction condition, uip-γ-Al 2 O 3 -CeO 2 -500 °C obtained remarkable 97 % yield of imine. After 20 days' continuous operation, the total isolated yield of imine and TON BA/CeO2 reached up to 81 % and 16838, respectively. Importantly, the catalyst could be reactivated in situ in the fixed reactor. Through detailed characterization, the extraordinary catalytic performance of uip-γ-Al 2 O 3 -CeO 2 -500 °C can be attributed to the abundant acid sites of γ-Al 2 O 3 as well as the synergistic effect between CeO 2 and γ-Al 2 O 3. [ABSTRACT FROM AUTHOR]