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There is a growing interest in anionic redox chemistry to improve the energy densities of rechargeable batteries, and the reversible chlorine/chloride reactions are a promising option for low-temperature applications. As such, understanding Cl adsorption on the cathode surfaces is important in revealing the intimate connection between catalysis and charge storage via the reversible surface Cl2/Cl− redox chemistry. In this work, we investigate the adsorption of Cl on various SrBO3 perovskites, with B being 3d transition metals, by using density functional theory calculations and interpretable machine learning. We identify the electronic structure descriptors crucial for Cl adsorption. Our findings reveal that SrCoO3 exhibits optimal Cl adsorption at the top of the volcano curve for Cl2 evolution, suggesting its potential as a catalyst to enable a low-temperature, liquid Cl2 electrode. 

ABSTRACT: It was found, using in situ infrared (IR) and X-ray (XAS) absorption spectroscopies together with density functional theory (DFT) calculations, that the binding energy of CO to Cu atoms in CuPtx/SBA-15 bimetallic catalysts does not vary linearly with Pt content but rather goes through a minimum at the diluted end, for x = 0.005, before increasing monotonically with further Pt addition. This behavior was observed both under vacuum and in equilibrium with gas-phase CO, and correlates with the trend observed for the C−O stretching frequency of the adsorbed CO. It is argued that the effect is due to changes in the extent of electron back-donation from the Cu d orbitals to the CO 2π* antibonding orbital induced remotely by Pt atoms at the nanoparticle/support interface. The observed trends also match that seen for the selectivity in the catalytic hydrogenation of unsaturated aldehydes to unsaturated alcohols. 

Two-dimensional transition metal carbides and nitrides (MXenes) are a class of materials that have drawn substantial attention for their diverse application, particularly in the field of energy storage. These materials are commonly derived from layered ternary solids, MAX phases, through etching processes. Efforts have been made to expand the scope of MXene synthesis beyond these top-down approaches to include bottom-up synthesis. Here we demonstrate a general direct synthetic route for scalable and atom-economic synthesis of various MXenes using different organohalide compounds as precursors for both carbon and surface termination groups. By reacting organochlorides (such as C2Cl4, C2Cl6 and CH2Cl2) or organobromides (CBr4 and CH2Br2) with transition metals, we synthesized a variety of MXenes (Ti2CCl2, Ti2CBr2, Zr2CCl2, Zr2CBr2 and Nb2CCl2), including a Nb2CBr2 MXene phase not accessed by other routes. The use of molecular precursors enables precise control of their reactivity, which allows the direct synthesis of MXene nanostructures. We demonstrate that nanometre-scale MXenes show higher surface reactivity compared with MXenes with micrometre-size flakes. 

Precision deuteration at metabolically vulnerable sites of pharmaceuticals can enhance drug stability and therapeutic efficacy, yet existing methods often suffer from poor selectivity and inefficiency. Here, we report an electricity-driven bromine-mediated deuteration strategy that enables late-stage site-selective deuteration of pharmaceuticals using D2O as the deuterium source. This approach involves a two-step process: (i) bromination of labile C–H bonds using Br2, followed by (ii) electricity-driven deuterodebromination using a palladium membrane reactor. This design leverages in situ Br2 generation at the anode and selective deuterium permeation through the palladium membrane cathode, thereby significantly improving atom economy and energy efficiency. Our method achieves nearly complete conversion and >90% deuterium incorporation for a range of aryl, heteroaryl, benzylic, and unactivated alkyl bromides, including ten marketed drug molecules. Furthermore, gram-scale synthesis of D-clonidine demonstrates the scalability of this approach. By integrating high selectivity, broad substrate scope, and operational efficiency, this method offers a practical solution for deuterated drug synthesis, with potential applications in pharmaceutical development and metabolic stabilization. 

Abstract Achieving both high redox activity and rapid ion transport is a critical and pervasive challenge in electrochemical energy storage applications. This challenge is significantly magnified when using large‐sized charge carriers, such as the sustainable ammonium ion (NH₄⁺). A self‐assembled MXene/n‐type conjugated polyelectrolyte (CPE) superlattice‐like heterostructure that enables redox‐active, fast, and reversible ammonium storage is reported. The superlattice‐like structure persists as the CPE:MXene ratio increases, accompanied by a linear increase in the interlayer spacing of MXene flakes and a greater overlap of CPEs. Concurrently, the redox activity per unit of CPE unexpectedly intensifies, a phenomenon that can be explained by the enhanced de‐solvation of ammonium due to the increased volume of 3 Å‐sized pores, as indicated by molecular dynamic simulations. At the maximum CPE mass loading (MXene:CPE ratio = 2:1), the heterostructure demonstrates the strongest polymeric redox activity with a high ammonium storage capacity of 126.1 C g⁻¹and a superior rate capability at 10 A g⁻¹. This work unveils an effective strategy for designing tunable superlattice‐like heterostructures to enhance redox activity and achieve rapid charge transfer for ions beyond lithium.