Chong Cheng

Converting CO ₂ into useful chemicals is a cornerstone of sustainable chemistry; among viable routes, the reverse water‐gas shift (RWGS) reaction supplies CO for subsequent fuel and olefin synthesis, yet achieving simultaneously high CO selectivity, fast CO ₂ activation, and stability with non‐noble metals remains elusive. Here, we employ a pure H ₂ torrent to rapidly reduce a Co‐salophen framework, forging a core‐shell Co@CoO _x ‐C catalyst consisting of a highly crystalline metallic Co core and a defect‐rich CoO _x shell capable of dynamic reconstruction under redox conditions. The metallic Co core dissociates H ₂ , driving hydrogen spillover to the metal‐oxide interface, where CO ₂ is efficiently activated, resulting in selective CO formation at the highly active Co/CoO _x boundary. Rapid CO desorption from coordinatively saturated CoO _x sites suppresses further hydrogenation, affording >99% CO selectivity and a CO formation rate of 254.0 mmol g _cat ⁻¹ h ⁻¹ at 500°C maintained for >100 h. These findings demonstrate that engineering dynamic Co/CoO _x interfaces via H ₂ torrent reduction overcomes the intrinsic selectivity limitations of cobalt‐based RWGS catalysts and highlight defect‐rich core‐shell structures derived from H ₂ ‐reduced metal‐salophen precursors as a versatile platform for next‐generation CO ₂ conversion technologies.

Developing radiosensitizing agents to amplify tumor-eradicating effects on primary, regional recurrence, and distant metastases plays a transformative role in modern cancer care. Here, we report the de novo design of biocatalytic artificial metalloenzymes with an IrMn-cluster-based redox center (IMM) to achieve radiosensitized systemic antitumor responses for preventing malignant tumor metastasis and recurrence. Notably, our findings indicate that Mn-organic ligands substantially enrich the electron density of Ir clusters, thereby optimizing their interaction with oxygen species and markedly enhancing the production of both reactive oxygen species and molecular oxygen. When combined with radiotherapy, the IMM effectively amplifies DNA damage and induces pronounced apoptosis by alleviating intratumoral hypoxia. This shift reprograms the tumor microenvironment, enhancing radiosensitivity and facilitating the infiltration and activation of intratumoral CD8⁺ T cells and dendritic cells. Moreover, when integrated with anti-PD-1 therapy, this coordinated therapeutic regimen elicits potent systemic immune responses and durable antitumor memory, effectively suppressing tumor recurrence and metastasis while markedly improving therapeutic efficacy and long-term survival. We anticipate that this conceptual design could offer a promising and translationally relevant nanomedicine platform for radiotherapies.

Bacterial infection poses a significant threat to clinical treatment due to the emergence of drug resistance and the high risk of recurrence. Here, we report the de novo design of a spiky pollen‐based vanadium artificial enzyme particle (VAE‐Pollen) that integrates potent reactive oxygen species (ROS)‐catalytic activity with immune priming to prevent both primary and secondary bacterial infections. Experimental and theoretical analyses confirm that bacteria are efficiently captured by the micro‐structured surface of VAE‐Pollen, and the introduction of oxygen vacancies modulates the electronic configuration of vanadium catalytic sites, significantly enhancing their versatile ROS‐catalytic performance. Meanwhile, VAE‐Pollen enhances bacterial capture and ROS‐triggered release of bacterial antigens, which mimics the sustained allergen exposure characteristic of natural pollen, thereby potently activating systemic defensive responses and providing sustained anti‐infective surveillance to prevent secondary wound infection. Notably, the VAE‐Pollen demonstrates significant efficacy in treating methicillin‐resistant Staphylococcus aureus ( MRSA ) and preventing its recurrence, offering a potent and intelligent antibacterial alternative that may circumvent the limitations of conventional antibiotics.

Covalent organic framework (COF)‐based photocatalysts hold considerable promise for solar‐driven chemical transformations, yet their practical performance in conventional powder or membrane systems is often constrained by poor dispersibility, inefficient interfacial mass transport, and suboptimal charge utilization. Here, we report COF‐based Janus membrane photocatalysts with an extended π‐conjugation for continuous photosynthesis of H ₂ O ₂ and value‐added chemicals, in which COF structures bearing expanded conjugated side chains are uniformly immobilized on the polyacrylonitrile (PAN) substrate to create a Janus‐like interfacial architecture. This design integrates the efficient light‐harvesting and charge‐transport capabilities of the COF framework with a PAN‐induced planar interface and tunable surface hydrophobicity. As a result, the Janus COF‐membrane exhibits enhanced hydrophobicity, achieving an H ₂ O ₂ production rate of 7888 µmol·g ⁻¹ h ⁻¹ under visible‐light irradiation, which is 2.23 times that of the control group, alongside excellent recyclability and long‐term operational stability. Furthermore, this straightforward approach can be extended to a range of COF‐derived photocatalysts for the photosynthesis of value‐added chemicals, which demonstrate superior activity in benzylamine coupling (99% conversion and selectivity within 3 h) and Knoevenagel condensation reactions (90%–99% conversion and selectivity within an average of 6 h). Together, our findings underscore the effectiveness of interfacial microenvironment engineering in designing COF membrane‐based photocatalytic systems.

The precise tuning of hydrogel properties using deep eutectic solvents (DESs) is fundamentally constrained by an unclear understanding of how the molecular structure of DES dictates hydrogel performance. Here, we demonstrated that the hydroxy-substituted alkane chain length of the hydrogen-bond donor in DESs nonmonotonically regulates the cross-linking density, water confinement, and mechanical properties of gelatin/carboxymethyl chitosan (CMCS) hydrogels. Systematic variation in the hydroxy-substituted alkane chain length from C2(carbon number of two) to C5 revealed that an optimal chain length (C3) maximized favorable noncovalent interactions, leading to a densely cross-linked network in DES-GC-3. The extensive hydrogen bonding between water and hydrogel constituents, coupled with this tightly cross-linked polymer network, collectively endowed DES-GC-3 with better mechanical strength and water retention. Due to the restriction of water mobility, DES-GC-3 also possessed a low freezing temperature of −62.9 °C, while maintaining excellent mechanical performance at −40 °C. Our work establishes the alkane chain length in DES as a fundamental, programmable parameter for the rational design of adaptive hydrogels through the precise modulation of polymer–solvent interactions.

The rapid evolution of antibiotic‐resistant bacteria, particularly methicillin‐resistant Staphylococcus aureus ( MRSA ), poses a critical threat to human healthcare, underscoring the need for antibiotic‐free antibacterial strategies that achieve both effective pathogen eradication and sustained protection against reinfection. Here, inspired by the functions of natural macrophages, we report the de novo design of an Ir/TiN‐based photothermal‐activable artificial macrophage (ITN Art‐M) with enhanced systemic antibacterial activity to combat primary and secondary infections caused by antibiotic‐resistant bacteria. The experimental studies and theoretical calculations reveal that the ITN Art‐M displays spiky topology, robust photothermal properties, and electron‐rich Ir‐Ti catalytic sites for reactive oxygen species (ROS) production, which can efficiently capture and kill antibiotic‐resistant bacteria. Meanwhile, the synthesized ITN Art‐M can induce severe bacterial antigen leakage and exposure through synergistic oxidative and hyperthermic stress, thereby potently stimulating systemic antibacterial responses, assisting in the elimination of primary infections and establishing durable defensive surveillance against secondary infections. Notably, ITN Art‐M demonstrates superior MRSA eradication and recurrence prevention, offering a potent, intelligent alternative that may surpass conventional antibiotics in combating bacteria and many other pathogenic cells.

The catalytic conversion of CO₂ into value-added chemicals via the reverse water-gas shift (RWGS) reaction represents a significant pathway for mitigating climate change and enabling sustainable carbon utilization. However, Pt-based catalysts, despite their superior H₂ activation ability, often suffer from inadequate CO selectivity and durability under high-temperature conditions, primarily due to excessive CO adsorption at low-coordinated Pt edge sites. Herein, we present a sulfur (S)-mediated targeted passivation strategy to engineer Pt-CeO₂ catalysts with atomically tailored active sites, effectively addressing the critical activity-stability-selectivity trade-off. The incorporation of S into CeO₂ support induced optimized electronic modulation, as evidenced by in situ/ex situ characterizations and density functional theory (DFT) calculations, which weakened *CO adsorption strength and suppressed the methanation pathway. The optimized Pt-S-CeO₂ catalyst exhibits remarkable performance at 600 °C: CO selectivity >95%, CO production rate of 8.8×10^-5mol g_cat^-1 s^-1, and 2 hydrogenation systems and beyond.