Xuebo Chen

Hydrogen production via MSR has attracted increasing attention as a promising strategy for on-demand hydrogen generation owing to the high hydrogen content, convenient storage and compatibility with existing fuel infrastructures of methanol.

This review discusses the photocatalytic cross-coupling of alkyl halides with C-, N-, O-, and S-nucleophiles via SET, conPET, or XAT, compared with traditional S _N 1/S _N 2 pathways, and is organized by bond-formation type (C(sp ³ )–C/N/O/S).

Cyclohexanol, as a key intermediate in the synthesis of nylon, faces critical issues in traditional production processes, such as low single-pass conversion and copper-based catalysts easily aggregating and deactivating. This study prepares hollow ceria nanosphere-supported copper catalysts (Cu/CeO2–HS) via a solvothermal method, calcination, and hydrogen reduction for the efficient hydrogenation of cyclohexyl acetate to cyclohexanol. Systematic characterization indicates that CeO2 has abundant oxygen vacancies, which can effectively stabilize the Cu+/(Cu0+Cu+) ratio. The hollow structure further improves the dispersion of active components, enhancing mass transfer. Highly dispersed Cu nanoparticles with surface-exposed Cu+ species form interfacial Cu–O–Ce sites, preventing aggregation and synergistically enhancing the activation of C═O bonds in cyclohexyl acetate. Under optimal conditions (250 °C, 3 MPa H2, 2 h), the optimal catalyst achieves 99.9% cyclohexyl acetate conversion with 97.5% selectivity to cyclohexanol. Importantly, it maintains the 99.8% conversion and 96.7% selectivity over five consecutive cycles without significant structural or chemical state change, demonstrating robust stability. This work addresses both the limitations of traditional processes and the issue of easy deactivation of copper-based catalysts by constructing a hollow structure and enhancing the interfacial interaction between Cu species and CeO2, providing a reliable catalytic solution for the green and efficient industrial production of cyclohexanol.

This report investigates the oxygen reduction reaction (ORR) catalyzed by single or dual atom-doped C2N (M-C2N) using the constant potential model (CPM) through grand-canonical density functional theory (GC-DFT). The findings for Fe-C2N, Sn-C2N, and Se-C2N indicate that Fe and Sn atoms become covered by OH groups, while Se is covered by O atoms, rendering these metal sites inactive. Instead, the actual active sites are the adjacent carbon atoms in the OH- or O-covered catalysts. Microkinetic simulations at pH 13 yield half-wave potentials of 0.80, 0.79, and 0.89 VRHE (vs. the reversible hydrogen electrode) for Fe-C2N, Sn-C2N, and Se-C2N, respectively, aligning well with experimental data. The reaction mechanisms are consistent across these catalysts, O2- mechanism: O2→O2-→*O2-→*OOH→*O→*OH→H2O . Further analysis reveals that the active sites and possible reaction pathways can be predicted using the reaction Gibbs free energy calculated under the charge neutral model (CNM) at the potential of zero charge (PZC). Applying this approach, ORR catalysis by Ti-C2N, Co-C2N, FeM-C2N (M = Sn, In, Sb, Bi, Ti, Pb), and SeM-C2N (M = Fe, Ni, Co, Cu, Mn, Mo) was predicted. In all cases, the metal atoms are covered by OH or O species and do not serve as active sites; instead, the nearby carbon atoms act as the active sites, following the same reaction mechanism: O2- mechanism. Furthermore, three universal principles have been established for ORR. First, the catalytic activity can be predicted exclusively through structural analysis without the need for computational calculations: specifically, if the metal atom adopts a tetrahedral geometry during the ORR process, it becomes covered by intermediates and consequently exhibits inactivity. Second, the free energy function G(U) derived by fitting the function F(n) demonstrates greater accuracy compared to directly fitting G(U). Third, the energy barriers for all electron chemistry steps are equal at the equilibrium potential U₀ and vary uniformly with changes in the applied potential.

Catalytic hydrogenation/dehydrogenation of carbon nitrogen bonds (-CH-NH-, -C=N-, -C≡N) represents fundamental transformations in synthetic chemistry and hydrogen storage. While significant advances have been made in hydrogenation or dehydrogenation individually, reversible interconversion using a single catalyst remains challenging. To address this challenge, we develop a copper-coordinated porous organic polymer (POP) catalyst featuring binuclear bis(imino)pyridine coordination units (dibis(imino)pyridine). This dibis(imino)pyridine-based POP catalyst could reversibly mediate both the dehydrogenation transformation of benzylamine compounds and the hydrogenation transformations of nitriles. Remarkably, both transformations proceed efficiently under mild conditions (water solvent, ≤80 ^oC) in the absence of precious metals, while demonstrating excellent catalytic recyclability with consistent product yields across successive cycles.

Photoinduced phosphorescent systems with high efficiency are constructed by doping weakly emissive hosts and guests. The doping systems exhibit high-contrast multi-stimuli response in both fluorescence and phosphorescence, which is rarely reported.

High-throughput DFT and interpretable ML identify Zr/g-C ₂ N and Ti/g-C ₂ NC as highly active and selective NO ₃ RR catalysts, suppressing HER and side reactions with limiting free-energy changes of 0.30 and 0.34 eV, respectively.

The formation of carbon─heteroatom bonds is a key strategy that enables the modular construction of molecules in synthetic chemistry, but activating inert carbonyl compounds to forge C─X bonds remains a longstanding synthetic challenge. Herein, we report a universal visible light‐driven photocatalytic system that enables efficient C─X (X = SS, S, Se) bond formation under mild, redox–neutral conditions. Guided by Marcus electron transfer theory, we employed a computational redox‐pair screening strategy to identify triplet‐state pathways with optimal electronic coupling matrix element (H _if ) and thermodynamic alignment. High‐level multireference calculations confirmed an ultrafast single‐electron transfer mechanism with ultrafast kinetics approaching the diffusion limit. To translate this mechanistic insight into a functional platform, we designed a dual‐functionalization strategy for α‐diketones, wherein one carbonyl acts as a conventional synthon while the other forms a light‐responsive dihydroquinazolinone (DHQZ) radical precursor. This system exhibits broad substrate scope, excellent functional group tolerance, and compatibility with late‐stage functionalization of bioactive scaffolds. Overall, this study establishes a general and mechanistically predictive photocatalytic strategy that transforms Marcus theory from a conceptual foundation into a design principle for efficient, light‐driven C─heteroatom bond construction.

The formation of carbon─heteroatom bonds is a key strategy that enables the modular construction of molecules in synthetic chemistry, but activating inert carbonyl compounds to forge C─X bonds remains a longstanding synthetic challenge. Herein, we report a universal visible light‐driven photocatalytic system that enables efficient C─X (X = SS, S, Se) bond formation under mild, redox–neutral conditions. Guided by Marcus electron transfer theory, we employed a computational redox‐pair screening strategy to identify triplet‐state pathways with optimal electronic coupling matrix element (H _if ) and thermodynamic alignment. High‐level multireference calculations confirmed an ultrafast single‐electron transfer mechanism with ultrafast kinetics approaching the diffusion limit. To translate this mechanistic insight into a functional platform, we designed a dual‐functionalization strategy for α‐diketones, wherein one carbonyl acts as a conventional synthon while the other forms a light‐responsive dihydroquinazolinone (DHQZ) radical precursor. This system exhibits broad substrate scope, excellent functional group tolerance, and compatibility with late‐stage functionalization of bioactive scaffolds. Overall, this study establishes a general and mechanistically predictive photocatalytic strategy that transforms Marcus theory from a conceptual foundation into a design principle for efficient, light‐driven C─heteroatom bond construction.