The electrode-electrolyte interface is pivotal in the electrochemical kinetics. However, modulating the electrochemical interface at the atomic or molecular level is challenging due to the lack of efficient interfacial regulators. Here, we employ a porous amine cage as an interfacial modifier to Pt cluster in a confining configuration, largely enhancing alkaline HER kinetics by facilitating charge transfer. In situ electrochemical surface-enhanced Raman spectra, in combination with the ab initio molecular dynamics simulation, elucidates that the interaction between water and the -NH- moiety of cage frame softens the H-bonds net of interfacial water, making it more flexible for charge transfer. Moreover, our investigation pinpointed that the -NH- moiety acted as a pump for charge transfer by Grotthuss mechanism, lowering the kinetic barrier for hydrogen adsorption. Our findings highlight the strategy of establishing a soft-confining interfacial modifier by porous cage, offering opportunities to optimize electrochemical interfaces and promote reaction kinetics in a targeted way.

The hydrogenation of glyoxylate oxime is the energy-intensive step in glycine electrosynthesis. To date, there has been a lack of rational guidance for catalyst design specific to this step, and the unique characteristics of the oxime molecule have often been overlooked. In this study, we initiate a theoretical framework to elucidate the fundamental mechanisms of glycine electrosynthesis across typical transition metals. By comprehensively analyzing the competitive reactions, proton-coupled electron transfer processes, and desorption steps, we identify the unique role of the glyoxylate oxime as a “readily activated molecule”. This inherent property positions Ag, featuring weak adsorption characteristics, as the “dream” catalyst for glycine electrosynthesis. Notably, a record-low onset potential of −0.09 V versus RHE and an impressive glycine production rate of 1327 µmol h⁻¹ are achieved when using an ultralight Ag foam electrode. This process enables gram-scale glycine production within 20 h and can be widely adapted for synthesizing diverse amino acids. Our findings underscore the vital significance of considering the inherent characteristics of reaction intermediates in catalyst design.

The Baeyer–Villiger (B–V) oxidation of ketones to the corresponding lactones/esters is a classic and essential reaction in the chemical industry. However, this oxidation process has not yet been achieved in ambient conditions with the aid of oxygen and heterogeneous photocatalysts. In this study, we developed an organic photocatalytic system using covalent triazine/heptazine-based frameworks (CTF-TB/CHF-TB) to enable the B–V oxidation reaction under mild conditions through a cascade reaction pathway. Experimental data and theoretical calculations showed that heptazine/triazine units can “chelate” and decompose the in situ generated H2O2 into hydroxyl radicals (⋅OH). Compared to conventional methods that primarily involve metal-activated benzaldehyde at elevated temperatures (e.g., 60 °C), the ⋅OH generated in our study can readily cleave the C−H bond of benzaldehyde, forming an active intermediate that drives subsequent sequential processes: O2→H2O2→⋅OH→Ph-CO⋅→Ph-COOO⋅. By employing this photocatalytic process, a yield of 91 % and a selectivity of over 99 % were obtained in the oxidation of cyclohexanone to caprolactone at room temperature. This performance is comparable to the state-of-the-art catalysts, and our CHF-TB catalyst demonstrates impressive reusability, maintaining a high yield after 5 consecutive runs. This work presents a straightforward approach for C−H cleavage by organocatalysts to produce ϵ-caprolactone in a mild manner by B–V oxidation.

Efficient and long-lasting electrocatalysts are one of the key factors in determining their large-scale commercial viability. Although the fundamentals of deactivation and regeneration of electrocatalysts are crucial for understanding and sustaining durable activity, little has been conducted on metalloids compared to metal-derived ones. Herein, by virtue of in situ seconds-resolved X-ray absorption spectroscopy, we discovered the chemical evolution during the deactivation-regeneration cycles of tellurium clusters supported by nitrogen-doped carbon (termed Te-ACs@NC) as a high-performance electrocatalyst in the hydrogen evolution reaction (HER). Through in situ electrochemical reduction, Te-ACs@NC, which had been deactivated due to surface phase transitions in a previous HER process, was reactivated and regenerated for the next run, where partially oxidized Te was found, surprisingly, to perform better than its nonoxidized state. After 10 consecutive deactivation-regeneration cycles over 480 h, the Te-ACs@NC retained 85% of its initial catalytic activity. Theoretical studies suggest that local oxidation modulates the electronic distribution within individual Te clusters to optimize the adsorption energy of water molecules and reduce dissociation energy. This study provides fundamental insights into the rarely explored metalloid cluster catalysts during deactivation and regeneration and will assist in the future design and development of supported catalysts with high activity and long durability.

3D printing as an advanced manufacturing technique provides an alternative cost-effective option for design and preparation of porous catalytic electrodes. Herein, carbonaceous catalytic electrodes with ternary dopants of boron (B), phosphorous (P), and nitrogen (N) (termed BPN-3Dp-CCEs) were successfully engineered via combination of the 3D printing technique and the following conformal carbonization of ionic liquid. The as-made electrodes were in turn applied to electrify CO₂ into syngas in a controllable composition of a H₂:CO molar ratio of 0.32–3.46. Notably, the BPN-3Dp-CCEs have tailored 3D macroscopic shapes of self-supporting skeletons, and due to ternary doping, demonstrated promoted catalytic activity in the electrocatalytic CO₂ conversion into syngas. Upon optimization, the electrode remained stable in structure and performance after 10 h of a continuous CO₂ electrolysis operation. This study casts insights and fuels the continuous exploration of multi-heteroatoms doped porous carbon electrodes for metal-free catalytic applications.

Actuators based on electrically conductive and hydrophilic two-dimensional (2D) Ti₃C₂T_X MXene are of interest for fast and specific responses in demanding environments, such as chemical production. Herein, Ti₃C₂T_X-based solvent-responsive bilayer actuators were developed, featuring a gradient polymer-intercalation structure in the active layer. These actuators were assembled using negatively charged pristine Ti₃C₂T_X nanosheets as the passive layer and positively charged polymer-tethered Ti₃C₂T_X as the active layer. 2D wide-angle X-ray scattering and simulations related the gradient polymer intercalated microstructure in the polymer/MXene composite active layer to the counterintuitive actuation behavior. The bending of the bilayer films in solvent vapor is triggered by the gradient polymer-intercalation and the differing diffusion rate of solvent molecules through the MX and MX-polymer layers of the bilayer actuator. With their ease of fabrication, remote light-control capabilities, and excellent actuation performance, the Ti₃C₂T_X-based bilayer actuators reported here may find applications in areas such as sensors for monitoring chemical production, infrared camouflage, smart switches, and excavators in toxic solvent environments.

Gold, often recognized as a luxury jewelry, plays an important role in diverse fields because of its specific physical and chemical properties. However, the limited supply and lack of abundance of gold led to continuous competition for its use. Therefore, industries have developed various techniques for gold mining and recycling, e.g., gold recovery from electronic waste (e-waste, commonly referred to as the gold bonanza). To address this challenge, a novel poly(ionic liquid)@covalent organic framework (PIL@COF) nanotrap for highly efficient gold recovery from e-waste is reported. The orderly arrangement of PIL facilitated by COF nanochannels, coupled with the strong binding affinity of PIL to gold (generated by its polycarbene intermediate) and the highly ordered porous COF architecture results in the rapid and selective capture of gold ions. This polycarbene@COF material achieves a gold adsorption capacity of up to 1.9 g g−1 and exhibits excellent sorption kinetics of 90% gold adsorption within 10 min while simultaneously reducing Au3⁺ to metallic Au0, which enables direct gold recovery and reuse. The high selectivity and efficiency of the gold recovery of this composite material are further confirmed by theoretical calculations. In addition, this polycarbene@COF nanotrap demonstrates high effectiveness across a wide pH range and maintains stability over multiple adsorption‒desorption cycles, highlighting its potential as a sustainable and robust platform for the recovery of precious metals.

Covalent organic framework (COF)-based electrolytes with abundant ordered channels and accessible interaction sites have shown great potential in energy storage and transformation, although their practical applications are strongly impeded by their inherent insolubility and non-melt processability. Developing processable COF gel electrolytes and recycling them remains a formidable challenge. In this study, the processing of COF to gels demonstrated through interlayer interaction manipulation and enable solution-reconstruction of COF gel electrolytes for the first time, inspired by the working principle of wedges. Good solution-processability of the COF powders in strong acid mediums is achieved by inserting oxygen atoms into its framework to promote the interlayer charge repulsion. This modification enabled the COF readily dispersable as colloidal nanosheets in an aqueous solution of trifluoroacetic acid (TFA). Starting from here, this is modulated competitive interactions among TFA, COF, and water molecules, to reconfigure COF materials between their gelified and colloidally dispersed states. The reconfigured COF gel maintains their mechanical properties and long cycle life as an electrolyte in the battery (>800 h). This approach realizes solution processing of COF powders and can recycle COF out of gels for repeated use, offering new insights and strategies for their preparation and sustainable recycling.

α-Alkylidene cyclic carbonates (αCCs) are gaining interest as building blocks in organic and polymer chemistry. To date, their synthesis via the coupling of CO₂ to propargylic alcohols has been restricted to batch processes, with extensive efforts devoted to improving catalytic systems. Herein, utilizing a refined, homogeneous silver–carbene–organobase catalytic system, we optimized batch conditions to achieve, for the first time, complete conversion of tertiary propargylic alcohols within minutes instead of hours. Building on this, we introduce a continuous flow methodology to produce a library of αCCs, achieving the highest space–time yields reported, with quantitative conversions in less than 20 minutes and outputs up to 111 grams per day. This approach reduces CO₂ usage to 1 or 2 equivalents, improves parameter control, and is expected to facilitate scalability. In addition, “plug-and-play” lab-scale continuous flow modules enable seamless integration of subsequent αCC transformations without intermediate purification, as illustrated by the aminolysis of αCCs into oxazolidones with good conversion (91%). Furthermore, supporting the silver–carbene catalyst on a polymer matrix eliminates silver contamination and even suppresses the need for a base co-catalyst. This work advances the scalable synthesis of αCCs via continuous flow, marking a significant step toward greener, CO₂-based cyclic carbonates and derivatives.

Homogeneous catalysts of high activity and selectivity often face challenges in the separation from feedstocks and products after reactions. In contrast, heterogeneous catalysts are easier to separate, usually at the cost of compromised catalytic performance. By designing catalysts capable of switching between homogeneous and heterogeneous states for catalysis and separation, the merits of both could be synergistically combined. In this study, a thermoresponsive 1,2,4-triazolium-based poly(ionic liquid) (PIL) was applied as a temperature-switchable organocatalyst for the controlled synthesis of porous organic cages in methanol. Variation of the reaction temperature induced a phase transition of the PIL, causing the polymer chains to dissolve or collapse in methanol, thereby exposing or shielding the catalytically active sites to proceed or retard the reaction, respectively. To note, at a sufficiently low temperature, the PIL as a catalyst precipitated out of its methanol solution and could be separated by centrifugation or filtration for reuse, similar to common heterogeneous catalysts. Such switchable and recyclable properties of polymeric catalysts will inspire the design of efficient and adaptable organic or hybrid nanoreactors in liquid media.