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Highlights By introducing fluorine modulation into MXene, a new MXene-derived material TiOF/Ti3C2 was successfully synthesized with a distinctive three-dimensional structure and a tailored F distribution. In situ characterizations and electrochemical analyses demonstrate that TiOF/Ti3C2 catalysts effectively coupled the multiphase sulfur species conversion processes. The investigations reveal that the theoretical basis of the fluorine catalysis in Li–S batteries originated from Lewis acid–base mechanisms and charge compensation mechanisms.

Abstract Porous carbons with concurrently high specific surface area and electronic conductivity are desirable by virtue of their desirable electron and ion transport ability, but conventional preparing methods suffer from either low yield or inferior quality carbons. Here we developed a lithiothermal approach to bottom–up synthesize highly meso–microporous graphitized carbon (MGC). The preparation can be finished in a few milliseconds by the self-propagating reaction between polytetrafluoroethylene powder and molten lithium (Li) metal, during which instant ultra-high temperature (>3000 K) was produced. This instantaneous carbon vaporization and condensation at ultra-high temperatures and in ultra-short duration enable the MGC to show a highly graphitized and continuously cross-coupled open pore structure. MGC displays superior electrochemical capacitor performance of exceptional power capability and ultralong-term cyclability. The processes used to make this carbon are readily scalable to industrial levels.

Abstract The metal-support interaction (MSI) in heterogeneous catalysts plays a crucial role in reforming reaction to produce renewable hydrogen, but conventional objects are limited to single metal and support. Herein, we report a type of RhNi/TiO2 catalysts with tunable RhNi-TiO2 strong bimetal-support interaction (SBMSI) derived from structure topological transformation of RhNiTi-layered double hydroxides (RhNiTi-LDHs) precursors. The resulting 0.5RhNi/TiO2 catalyst (with 0.5 wt.% Rh) exhibits extraordinary catalytic performance toward ethanol steam reforming (ESR) reaction with a H2 yield of 61.7%, a H2 production rate of 12.2 L h−1 gcat −1 and a high operational stability (300 h), which is preponderant to the state-of-the-art catalysts. By virtue of synergistic catalysis of multifunctional interface structure (Rh-Ni δ−-O v -Ti3+; O v denotes oxygen vacancy), the generation of formate intermediate (the rate-determining step in ESR reaction) from steam reforming of CO and CH x is significantly promoted on 0.5RhNi/TiO2 catalyst, accounting for its ultra-high H2 production.

Traditional approaches for transition-metal catalyzed oxidative cross-coupling reactions rely on sp 2-hybridized starting materials. Here the authors report a heterogeneous Pd-catalyzed radical relay method for the conversion of a heteroarene C(sp 3)–H bond into ethers.

Catalytic hydrogenation of available nitroarenes is an environmentally benign and recyclable approach to synthesize value-added amines. Here, the authors design a RuNi single atom alloy with host-dopant synergistic effect, which exhibits outstanding performance toward nitroarenes hydrogenation.

Chemical electron microscopy (CEM), a toolbox that comprises imaging and spectroscopy techniques, provides dynamic morphological, structural, chemical, and electronic information about an object in chemical environment under conditions of observable performance. CEM has experienced a revolutionary improvement in the past years and is becoming an effective characterization method for revealing the mechanism of chemical reactions, such as catalysis. Here, we mainly address the concept of CEM for heterogeneous catalysis in the gas phase and what CEM could uniquely contribute to catalysis, and illustrate what we can know better with CEM and the challenges and future development of CEM.

Abstract Water splitting has been proposed to be a promising approach to producing clean hydrogen fuel. The two half‐reactions of water splitting, that is, the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), take place kinetically fast in solutions with completely different pH values. Enabling HER and OER to simultaneously occur under kinetically favorable conditions while using exclusively low‐cost, earth‐abundant electrocatalysts is highly desirable but remains a challenge. Herein, we demonstrate that using a bipolar membrane (BPM) we can accomplish HER in a strongly acidic solution and OER in a strongly basic solution, with bifunctional self‐supported cobalt‐nickel phosphide nanowire electrodes to catalyze both reactions. Such asymmetric acid/alkaline water electrolysis can be achieved at 1.567 V to deliver a current density of 10 mA/cm2 with ca. 100% Faradaic efficiency. Moreover, using an “irregular” BPM with unintentional crossover the voltage needed to afford 10 mA/cm2 can be reduced to 0.847 V, due to the assistance of electrochemical neutralization between acid and alkaline. Furthermore, we show that BPM‐based asymmetric water electrolysis can be accomplished in a circulated single‐cell electrolyzer delivering 10 mA/cm2 at 1.550 V and splitting water very stably for at least 25 hours, and that water electrolysis is enabled by a solar panel operating at 0.908 V (@13 mA/cm2), using an “irregular” BPM. BPM‐based asymmetric water electrolysis is a promising alternative to conventional proton and anion exchange membrane water electrolysis.

Gold is among the least active metals toward molecules at a solid-liquid or solid-gas interface. Here the authors demonstrate that the gold nanocatalysts with d electron gain due to C occupying interstitial sites in its lattice boost catalytic hydrogenation.

Phosphorus ligands have been extensively used in metal complexes for homogeneous catalysis. Here, the authors broaden this scope to heterogeneous catalysis by preparing a P-coordinated Fe single atom catalyst with excellent catalytic performance in hydrogenative transformations.

Design and synthesis of non-noble metal catalysts is crucial for highly-efficient hydrogenation. Here, the interstitial sites in nickel are manipulated with zinc and filled by dissociated carbon atoms, which drastically improve the selectivity/stability in acetylene hydrogenation reaction.

The development of sintering resistant supported Au catalysts with high activity still remains a challenge. Here the authors construct a Au-SiO2 interface by depositing SiO2 thin layer onto Au/TiO2 catalyst which shows very high activity in CO oxidation even after calcination at 800 °C.

Long-chain alcohols synthesis from syngas conversion is a promising route for the production of high-value chemicals. Here the authors show that a heterogeneous Fe5C2/Cu catalyst derived from layered double hydroxides precursor exhibits excellent performance with a space time yield of 0.101 g gcat −1 h−1 at a low pressure of 1 MPa.

Sintering-resistant Au nanoparticles are highly desirable due to their low Tammann temperature. Here, the authors report an ultrastable titania-supported Au nanocatalyst through an encapsulation strategy under oxidative atmosphere.

Single-atom catalysts maximize atom usage within supports, but preparations can be complex. Here, authors show a facile impregnation-adsorption method to attach single noble-metal atoms to N-doped porous carbon and demonstrate strong electrocatalytic hydrogen evolution performances for Pt catalysts.

Summary: Development of synergistic heterogeneous catalysts with active sites working cooperatively has been a pursuit of chemists. Herein, we report for the first time the fabrication and manipulation of Pt-WO3 dual-active-sites to boost hydrogen generation from ammonia borane. A combination of DFT calculations, structural characterization, and kinetic (isotopic) analysis reveals that Pt and WO3 act as the active sites for ammonia borane and H2O activation, respectively. A trade-off between the promoting effect of WO3 and the negative effect of decreased Pt binding energy contributes to a volcano-shaped activity, and Pt/CNT-5W delivers a 4-fold increased activity of 710.1 molH2·molPt−1·min−1. Moreover, WO3 is suggested to simultaneously act as the sacrificial site that can divert B-containing by-products away from Pt sites against deactivation, yielding an increase from 24% to 68% of the initial activity after five cycles. The strategy demonstrated here could shed a new light on the design and manipulation of dual-active-site catalysts. : Inorganic Chemistry; Catalysis; Nanomaterials Subject Areas: Inorganic Chemistry, Catalysis, Nanomaterials

Protein lipidation plays critical roles in regulating protein function and localization. However, the chemical diversity and specificity of fatty acyl group utilization have not been investigated using untargeted approaches, and it is unclear to what extent structures and biosynthetic origins of S-acyl moieties differ from N-and O-fatty acylation. Here, we show that fatty acylation patterns in Caenorhabditis elegans differ markedly between different amino acid residues. Hydroxylamine capture revealed predominant cysteine S-acylation with 15-methylhexadecanoic acid (isoC17:0), a monomethyl branched-chain fatty acid (mmBCFA) derived from endogenous leucine catabolism. In contrast, enzymatic protein hydrolysis showed that N-terminal glycine was acylated almost exclusively with straight-chain myristic acid, whereas lysine was acylated preferentially with two different mmBCFAs and serine was acylated promiscuously with a broad range of fatty acids, including eicosapentaenoic acid. Global profiling of fatty acylated proteins using a set of click chemistry-capable alkyne probes for branched-and straight-chain fatty acids uncovered 1,013 S-acylated proteins and 510 hydroxylamine-resistant N-or O-acylated proteins. Subsets of S-acylated proteins were labeled almost exclusively by either a branched-chain or a straight-chain probe, demonstrating acylation specificity at the protein level. Acylation specificity was confirmed for selected examples, including the S-acyltransferase DHHC-10. Last, homology searches for the identified acylated proteins revealed a high degree of conservation of acylation site patterns across metazoa. Our results show that protein fatty acylation patterns integrate distinct branches of lipid metabolism in a residue-and protein-specific manner, providing a basis for mechanistic studies at both the amino acid and protein levels. [ABSTRACT FROM AUTHOR]

Electrocatalysts that possess high densities of surface defects show great promise for efficient water oxidation. Here the authors demonstrate that regulating the p-block metal content in perovskite nanodots imparts these materials with abundant surface defects and excellent electrocatalytic activity.

High-performance electrocatalysts for the oxygen reduction reaction (ORR) typically use platinum (Pt), however its high cost is a hindrance to commercial scale up. Here, the authors report a cost-effective, efficient and durable Pt single-atom electrocatalyst for ORR with a Pt utilization of 0.13 gPt kW−1in a fuel cell.