Developing efficient, stable, and inexpensive catalysts for the preferential CO oxidation in H₂ (CO-PROX) over a wide temperature range in the presence of CO₂ and H₂O is indispensable for the hydrogen purification process. Herein, CuO was introduced to the CeMnO₂-supported Pt catalyst to modulate the oxygen activation capacity and provide the available number of active sites in CO-PROX. One part of the CuO species doped into CeO₂ strongly interacts with Ce, thus enhancing the oxygen transfer capacity of the catalyst. The other part of CuO species located on the surface of the catalyst provides extra Cu⁺ sites available for low-temperature CO adsorption. This synergistic interaction with Pt sites further enhances CO and O₂ activation, broadening the temperature window of high activity. The optimal Pt-10CuO/CeMnO₂ catalyst exhibits complete CO conversion (CO/O₂ ratio of 1:1) within the practical temperature range of 130–190 °C, even in the presence of CO₂ and H₂O, and remains stable at 150 °C for 76 h testing without any deactivation. This work will give a novel approach for the design of highly efficient inexpensive catalysts for industrial preferential oxidation of CO in H₂, especially in the presence of CO₂ and H₂O.

We investigated the pivotal role of active center symmetry on the stability of reactant adsorption and the transition state dynamics within the context of acetylene hydrochlorination. Our innovative approach involved the integration of phosphorus into a nitrogen-doped carbon framework and introduced the single Cu center, culminating in the development of novel copper-nitrogen-phosphorus-carbon (Cu-NPC) catalysts. These catalysts are distinguished by their asymmetrical Cu₁-N₃-P-C chemical environment. Our kinetic studies shed light on the underlying mechanisms contributing to the superior performance of the Cu-NPC catalysts. These catalysts not only enhance the reaction rate by moderating the adsorption strength of reactants, thereby optimizing the reaction kinetics, but also demonstrate an outstanding ability to mitigate the risk of carbon deposition, a common challenge that compromises catalyst longevity and efficiency. This is evidenced by a notably low deactivation rate of 0.027 h⁻¹ at a high C₂H₂ weight hourly space velocity (WHSV) of 1.4 ${\text{g}}_{{\text{C}}_2{\text{H}}_2}\cdot {{\text{g}}_{\text{cat}}}^{-1}\cdot {\text{h}}^{-1}$. This research not only advances our understanding of the critical influence of active center symmetry on catalyst performance but also paves the way for the rational design of advanced catalysts tailored for specific industrial applications.

At present, the catalysts commercially used for the oxygen reduction reaction of the cathode of proton exchange membrane fuel cells (PEMFCs) are carbon-supported platinum-based catalysts. However, the carbon supports are susceptible to corrosion under harsh working conditions, which greatly shortens the life of the catalysts. Highly stable carbon supports are urgently required for high-performance PEMFCs. In this work, we developed structure-stable and highly graphitized three-dimensional network carbon nanofibers (CNF) derived from polyaniline by heat treatment at 1200 °C. The CNF-1200-based catalyst (PtNi/CNF-1200) loaded with PtNi nanoparticles showed excellent stability. After 5000 cycles from 1.0 to 1.5 V in oxygen saturated 0.1 M HClO₄ electrolyte, the losses in the half-wave potential and mass activity were only 5 mV and 15%, respectively, far lower than those of commercial Pt/C. The high graphitization degree of CNF-1200 promotes the corrosion resistance of the catalyst. In addition, nitrogen doping effectively facilitates the catalyst–support interaction, stabilizes the highly dispersed PtNi nanoparticles, and improves the stability and activity of PtNi/CNF-1200.

Activated carbon-supported HgCl₂ catalysts have seriously impeded the development of the polyvinyl chloride (PVC) industry due to the sublimation of Hg species and environmental pollution problems. Herein, the template-free and organic solvent-free strategy was devised to synthesize non-metallic based nitrogen-doped carbon (U-NC) sphere catalyst for acetylene hydrochlorination. This green strategy via ultrasonic chemistry initiates resin crosslinking reactions between aminophenol and formaldehyde resin by free radicals, leading to the ultra-rapid formation of U-NC with remarkably high pyrrolic N content in only 5 min. This U-NC catalyst exhibited an outstanding space-time-yield (1.6 g_VCM·g_cat⁻¹·h⁻¹), even comparable to the reported metallic catalyst. By combining kinetic analysis, advanced characterizations, and density functional theory, it is found that the amount of pyrrolic N is in linear with C₂H₂ conversion, and pyrrolic N in U-NC can effectively improve acetylene hydrochlorination performance by mediating HCl adsorption. This work sheds new light on rationally constructing metal-free catalyst for acetylene hydrochlorination.

Reverse water gas shift (RWGS) catalysis, a prominent technology for converting CO₂ to CO, is emerging to meet the growing demand of global environment. However, the fundamental understanding of the reaction mechanism is hindered by the complex nature of the reaction. Herein, microkinetic modeling of RWGS on different metals (i.e., Co, Ru, Fe, Ni, Cu, Rh, Pd, and Pt) was performed based on the DFT results to provide the mechanistic insights and achieve the catalyst screening. Adsorption energies of the carbon-based species and the oxygen-based species can be correlated to the adsorption energy of carbon and oxygen, respectively. Moreover, oxygen adsorption energy is an excellent descriptor for the barrier of CO₂ and CO direct dissociation and the difference in reaction barrier between CO₂ (or CO) dissociation and hydrogenation. The reaction mechanism varies on various metals. Direct CO₂ dissociation is the dominating route on Co, Fe, Ru, Rh, Cu, and Ni, while it competes with the COOH-mediated path on Pt and Pd surface. The eights metals can be divided into two groups based on the degree of rate control analysis for CO production, where CO–O bond cleavage is rate relevant on Pt, Pd, and Cu, and OH–H binding is rate-controlling on Co, Fe, Ru, Ni, and Rh. Both CO-direct dissociation and hydrogen-assisted route to CH₄ contribute to the methane formation on Co, Fe, Pt, Pd, Ru, and Rh, despite the significant barrier difference between the two routes. Besides, the specific rate-relevant transition states and intermediates are suggested for methane formation, and thus, the selectivity can be tuned by adjusting the energy. The descriptor (C- and O- formation energy) based microkinetic modeling proposed that the activity trend is Rh~Ni > Pt~Pd > Cu > Co > Ru > Fe, where Fe, Co, Ru, and Ni tends to be oxidized. The predicted activity trend is well consistent with those obtained experimentally. The interpolation concept of adsorption energy was used to identify bimetallic materials for highly active catalysts for RWGS.