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Sustainable production of bio-based chemicals from renewable feedstocks is crucial for a carbon-neutral chemical economy. The hydrogenolysis of glycerol, a major biodiesel by-product, into 1,2-propanediol offers an atom-efficient route to high-value C₃ chemicals. Conventional Cu-based catalysts often require high Cu loadings and suffer from deactivation via sintering or leaching, limiting their use in continuous fixed-bed processes. Here, an La-modified Cu/Al₂O₃ catalyst (CuLa2/A-R) was rationally designed for continuous hydrogenolysis of concentrated glycerol. La incorporation enhanced Cu dispersion, strengthened metal–support interactions, and converted weak Brønsted acid sites into medium–strong Lewis acid sites. These synergistic effects enabled high activity and exceptional stability under industrially relevant conditions. With only ∼9 wt.% Cu, the catalyst maintained outstanding performance for 50 wt.% glycerol and operated stably for over 500 h without significant deactivation. This study not only delivers a high-performance and environmentally benign Cu-based catalyst with strong potential for industrial application but also elucidates the multifaceted role of rare-earth promoters in tuning metal–support interfacial properties and acid–base structures. The insights gained herein provide valuable guidance for the rational design of next-generation Cu-based catalysts for sustainable biomass conversion.

Bismuth metal and its oxides are common catalysts for electrochemical CO₂ reduction (CO₂R) to HCOOH, although they tend to suffer from lower activity due to poor conductivity. Here we investigated a bismuth selenide catalyst which adopted a spiral-nanoplate morphology. The catalyst had a mass activity of 31 mA mg⁻¹ for HCOOH at -0.9 V RHE, double that of commercial Bi₂Se₃ powder, nearly ten-times that of commercial Bi (16 mA mg⁻¹ and 3.8 mA mg⁻¹ respectively), and competitive with other contemporary Bi-based catalysts. It also possessed greater stability than these counterparts. The higher mass activity of spiral Bi₂Se₃ occurred alongside a lower charge transfer resistance (78 Ω) than commercially available Bi₂Se₃ or Bi (314 Ω and 247 Ω respectively). These characteristics of spiral Bi₂Se₃ were attributed to the presence of a unique Bi₂Se₃/Bi⁰ heterostructure formed from the depletion of Se from the near-surface region of the material during electrocatalysis. The lower charge transfer resistance of the Bi₂Se₃/Bi⁰ heterostructure, relative to Bi and commercial Bi₂Se₃, resulted in catalytic sites that were more active for the kinetically complex CO₂R reaction.

This work reports the systematic evaluation of the synthetic route used to prepare several layered hydroxide salts (LHS) based on nitrate salts of cobalt, copper, nickel, and zinc and their physicochemical and catalytic properties. Four synthetic methods were investigated: hydrothermal (H), ammonia diffusion (A), mechanochemical (M), and precipitation (P) and the LHS obtained were characterized by different techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The influence of the four synthetic methods on the structure of the prepared LHS is discussed, as well as the impacts on their catalytic activity. The synthesized LHS were employed as catalysts for the ketalization of cyclohexanone with methanol and it was observed that the changes in the metal (II) and different synthetic method used to prepare the LHS lead to a substantial impact in the catalytic results, suggesting that these variables are important tools to direct the best and appropriate use of this family of layered solids.

The controlled stabilization of non-noble metal species for propane dehydrogenation (PDH) remains challenging due to their intrinsic tendency toward aggregation and oxidation-state drift. Here, we demonstrate that silanol nests within dealuminated Beta zeolites act as defect-engineered anchoring centers that regulate the polymerization of vanadium oxides (VO_x). Systematic manipulation of silanol density through dealumination, thermal condensation, and sodium passivation reveals a positive correlation among silanol-nest population, vanadium dispersion, and PDH performance. The optimized V_1%/DeAlBeta catalyst achieves a high propylene formation rate of 1.93 mol_C3H6 g_V⁻¹ h⁻¹, a low deactivation rate (0.0067 h⁻¹) at 580°C, and excellent long-term stability and regenerability across eight consecutive redox cycles. Comprehensive spectroscopic analyses identify cooperative silanol–VO_x interactions that stabilize isolated and low-polymerized vanadium species, whereas depletion of silanol nests triggers the formation of polymeric VO_x domains with diminished activity. These results highlight a defect-directed confinement strategy to stabilize earth-abundant metal sites and offer conceptual guidelines for designing environmentally benign and cost-effective PDH catalysts.

The electrochemical CO₂ reduction reaction (ECO₂RR) has emerged as a promising strategy for transforming CO₂ into value-added chemicals and fuels. However, the weak adsorption strength of *COO⁻ significantly hindered CO formation on the active surface sites of Ag. Herein, the nanostructured silver phosphate (Ag₃PO₄) catalyst revealed that PO₄³⁻ promoted the formation of key intermediates, *COO⁻ and *COOH, with in situ Raman spectroscopy. The Ag₃PO₄ catalyst was prepared via a complexation-precipitation method, which showed excellent performance in the selective reduction of CO₂ to CO. Notably, Ag₃PO₄ undergoes structural reconstruction during electrochemical operation, leading to the formation of Ag/Ag₃PO₄ as the dominant active sites. This reconstruction enables consistently delivered Faradaic efficiencies for CO (FE_CO) exceeding 95% over a wide potential window from −0.477 V to −1.077 V versus RHE, with FE_CO surpassing 98% between −0.477 and −0.877 V versus RHE. It was demonstrated that a partial CO current density of 146 mA cm⁻² at -0.777 V versus RHE was achieved in the flow cell, approximately a 2.5-fold increase over that achieved by pure silver. This work presents a phosphate-based catalyst design, demonstrating potential for application in ECO₂RR.

Catalytic methane decomposition (CMD) offers a promising route for hydrogen production without CO₂ emissions, while simultaneously generating valuable carbon nanostructures. In this study, iron-based catalysts supported on alumina and lanthana-modified alumina were synthesized and evaluated in a fixed-bed reactor at 700 °C under atmospheric pressure. The 20Fe/La─Al catalyst exhibited superior performance, achieving the highest hydrogen production rate (0.44 mmol/g_M/s) and stable methane conversion (from initial conversion of 70.2% to final value of 79.5%) compared to Fe/Al (demonstrating deactivation from initial conversion of 74.3% to final value of 22.7%) and previously reported systems. Characterization using XRD, TPR, SEM, HRTEM, and TGA revealed that lanthana modification significantly improved iron dispersion, reducibility, and metal–support interaction, leading to enhanced catalytic activity and stability. TG/DTG analysis confirmed higher carbon deposition and better graphitization for lanthana-modified catalysts, while HRTEM images verified the formation of high-purity multi-walled carbon nanotubes. These findings highlight the critical role of support modification in optimizing catalyst properties for efficient hydrogen generation and carbon nanotube production via CMD.

The liquid-phase selective oxidation of benzyl alcohol (BZA), particularly conducted under solvent-free conditions using atmospheric O₂ as the oxidant, represents a sustainable approach for benzaldehyde (BZL) synthesis. Among numerous heterogenous catalysts developed, supported Pd nanoparticles have showed high activity and selectivity for this process. Herein, to further upgrade the activity of the Pd-based catalysts, graphitic carbon nitride (g-C₃N₄) was employed as a support for Pd–Au bimetallic nanocatalysts (Pd_xAu_y/g-C₃N₄-T). The supported Pd and Au formed alloy nanoparticles, with the introduction of Au reducing the particle size of the supported metals. Moreover, strong interaction between the nitrogen atoms in the g-C₃N₄ support and the supported metals was evidenced. In the liquid-phase and solvent-free selective oxidation of BZA with O₂, the bimetallic catalysts exhibited higher catalytic activity than their monometallic counterparts. Under mild reaction conditions (90°C and 6 h), merely 20 mg of 1Pd₃Au₁/g-C₃N₄-350 catalyst achieved a high BZL yield of 62.7%. Furthermore, the catalyst can be reused at least six times without any loss of activity and meanwhile exhibited activity toward other aromatic alcohols.

Due to increasing demand for sustainable energy systems, hydrogen energy, as a green and low-carbon energy carrier, has considerable potential for development. The electrocatalytic water splitting is one of the key ways to produce green hydrogen, but high costs and resource limitations of Pt-based catalysts limit their large-scale use. As a result, exploring high-performance, low-cost non-noble metal HER catalysts have emerged as a research focus. This work has been focused on the investigation of FeCrNiZrMn/CNFs high-entropy alloy catalysts. A series of catalyst materials were prepared through electrospinning techniques with subsequent high-temperature carbonization at 700°C–900°C. The experimental results showed that the FeCrNiZrMn/CNFs synthesized at 800°C could form uniformly distributed and crystallographically stable high-entropy alloy nanoparticles, achieving exceptional performance for the HER under alkaline conditions, with an overpotential of 57 mV at 10 mA/cm² and a Tafel slope of 29.2 mV/dec, and maintaining 99.3% voltage stability during a 16-h constant current test. Theoretical results from DFT suggested that the high-entropy alloy surface has diverse hydrogen adsorption sites and a tunable electronic structure. The differential charge density analysis furthers interpretation of the electron transfer behavior during hydrogen adsorption, and reveals the intrinsic mechanism of its efficient catalysis.

Perovskites with tunable compositions and structures are desirable electrocatalysts for water electrolysis. However, achieving efficient hydrogen evolution reaction (HER) in alkaline media using perovskite-based catalysts remains a significant challenge. Herein, a Cu-doped La_0.5Ba_0.5CoO_3–δ perovskite was synthesized via a sol-gel method, which exhibits enhanced HER electrocatalytic activity through the construction of dual active sites. X-ray photoelectron spectroscopy (XPS) and x-ray absorption fine structure (XAFS) analyses reveal that Cu doping simultaneously induces the oxidation of Co and the formation of oxygen vacancies, establishing a synergistic charge compensation between the dual active sites. Specifically, oxygen vacancies promote water dissociation by enhancing adsorption, while high-valence Co species reduce charge transfer resistance, thereby facilitating electron transfer during HER. As a result, the optimized La_0.5Ba_0.5Co_0.8Cu_0.2O_3–δ (LBCC_0.2) achieves low overpotentials of 160 mV and 228 mV at current densities of 10 and 100 mA·cm⁻², respectively. Moreover, the catalyst demonstrates outstanding stability, maintaining 200 h for HER operation, outperforming commercial Pt/C. This study highlights the advantage of dual active sites in boosting the intrinsic electrochemical activity and underscores the potential of Cu-doped perovskites for efficient hydrogen production.

This study elucidates the crucial role of 2-cyanopyridine as a dehydrating agent in altering the catalytic mechanism of praseodymium-doped ceria (Pr–CeO₂) for ethylene carbonate (EC) synthesis from ethylene glycol (EG) and CO₂. In the presence of 2-cyanopyridine, the Pr–CeO₂ catalyst achieved an exceptional EC yield of 99.9% and a high turnover frequency (TOF) of 58.1 mmol g⁻¹ h⁻¹. Remarkably, removing 2-cyanopyridine led to a 95.4% decrease in TOF, yielding only 2.71 mmol g⁻¹ h⁻¹. Mechanistic studies demonstrate that 2-cyanopyridine shifts the active sites from moderate-strength acid–base pairs to weak acid–base sites, leading to divergent catalytic pathways. Comprehensive characterization confirms that 2-cyanopyridine promotes surface site modification and intermediate transformation, thereby significantly reducing the activation energy for EC formation. This work provides a strategic basis for optimizing dehydrating agents in catalytic carbonylation of alcohols with CO₂.