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Abstract The limited durability of metal-nitrogen-carbon electrocatalysts severely restricts their applicability for the oxygen reduction reaction in proton exchange membrane fuel cells. In this study, we employ the chemical vapor modification method to alter the configuration of active sites from FeN4 to the stable monosymmetric FeN2+N’2, along with enhancing the degree of graphitization in the carbon substrate. This improvement effectively addresses the challenges associated with Fe active center leaching caused by N-group protonation and free radicals attack due to the 2-electron oxygen reduction reaction. The electrocatalyst with neoteric active site exhibited excellent durability. During accelerated aging test, the electrocatalyst exhibited negligible decline in its half-wave potential even after undergoing 200,000 potential cycles. Furthermore, when subjected to operational conditions representative of fuel cell systems, the electrocatalyst displayed remarkable durability, sustaining stable performance for a duration exceeding 248 h. The significant improvement in durability provides highly valuable insights for the practical application of metal-nitrogen-carbon electrocatalysts.

Abstract CO2 hydrogenation to chemicals and fuels is a significant approach for achieving carbon neutrality. It is essential to rationally design the chemical structure and catalytic active sites towards the development of efficient catalysts. Here we show a Ce-CuZn catalyst with enriched Cu/Zn-OV-Ce active sites fabricated through the atomic-level substitution of Cu and Zn into Ce-MOF precursor. The Ce-CuZn catalyst exhibits a high methanol selectivity of 71.1% and a space-time yield of methanol up to 400.3 g·kgcat −1·h−1 with excellent stability for 170 h at 260 °C, comparable to that of the state-of-the-art CuZnAl catalysts. Controlled experiments and DFT calculations confirm that the incorporation of Cu and Zn into CeO2 with abundant oxygen vacancies can facilitate H2 dissociation energetically and thus improve CO2 hydrogenation over the Ce-CuZn catalyst via formate intermediates. This work offers an atomic-level design strategy for constructing efficient multi-metal catalysts for methanol synthesis through precise control of active sites.

Abstract Heterogeneous nano-electrocatalysts doped with nonmetal atoms have been studied extensively based on the so-called dopant-based active sites, while little attention has been paid to the stability of these dopants under working conditions. In this work, we reveal significantly, when the redox working potential is too low negatively or too high positively, the active sites based on these dopants actually tend to collapse. It means that some previously observed “remarkable catalytic performance” actually originated from some unknown active sites formed in situ. Take the Bi-F for the CO2RR as an example, results show that the observed remarkable activity and stability were not directly from F-based active sites, but the defective Bi sites formed in situ after the dopant leaching. Such a fact is unveiled from several heteroatom-doped nanocatalysts for four typical reactions (CO2RR, HER, ORR, and OER). This work provides insight into the role of dopants in electrocatalysis.

Abstract Single-site pincer-ligated iridium complexes exhibit the ability for C-H activation in homogeneous catalysis. However, instability and difficulty in catalyst recycling are inherent disadvantages of the homogeneous catalyst, limiting its development. Here, we report an atomically dispersed Ir catalyst as the bridge between homogeneous and heterogeneous catalysis, which displays an outstanding catalytic performance for n-butane dehydrogenation, with a remarkable n-butane reaction rate (8.8 mol·gIr −1·h−1) and high butene selectivity (95.6%) at low temperature (450 °C). Significantly, we correlate the BDH activity with the Ir species from nanoscale to sub-nanoscale, to reveal the nature of structure-dependence of catalyst. Moreover, we compare Ir single atoms with Pt single atoms and Pd single atoms for in-depth understanding the nature of metal-dependence at the atomic level. From experimental and theoretical calculations results, the isolated Ir site is suitable for both reactant adsorption/activation and product desorption. Its remarkable dehydrogenation capacity and moderate adsorption behavior are the key to the outstanding catalytic activity and selectivity.

Scalable synthesis of stable Cu clusters for heterogeneous catalysis is still a major challenge. Here the authors report a low-temperature atomic diffusion approach for synthesis of stable Cu cluster catalysts, which exhibit high yield of intermediate product in consecutive hydrogenation reactions.

The poor stability of ruthenium-based catalysts has greatly hampered their application in polymer electrolyte membrane water electrolysis. Here, the authors uncover the decisive role of reaction route on catalytic performance, which enables the screening of efficient ruthenium-based water oxidation catalysts.

The preferential oxidation of CO (PROX) in hydrogen is a promising solution for hydrogen purification. Here the authors report a novel bimetallic Pt-Fe catalyst with ultralow metal loading which delivers excellent catalytic activity and selectivity in PROX, while maintains good stability for a long period.

Zhong et al report sodium-promoted metallic Ru nanoparticles for the direct production of olefins from syngas with ultrahigh carbon efficiency where the total selectivity of undesired CH4 and CO2 is suppressed to only 5% for over 500 hours on stream.

Quantitatively describing the atomic configuration of the catalytically active sites is challenging. Here the authors demonstrate that tuning crystal-phase of metal single-particle enables to precisely describe the atomic structure of the active sites and accurately identify the activation routes of the reacting molecules.

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.

Developing single atom systems with improved catalytic potential for bio-application has major therapeutic potential. Here, the authors report on the development of a metal single-atom on a carbon dot support confined within mesoporous silica for the development of therapeutic agents.

H2 is regarded as an attractive green fuel and a promising energy carrier for the future. Here, the promotion functions of reverse spillover effects in the H2 generation reactions over bicomponent catalysts are revealed by performing in situ X ray absorption near edge structure characterization.

A molecular-level understanding of the electronic effects remains a grand challenge in heterogeneous catalysis. Here, the authors report an unconventional kinetics strategy for bridging the upscaling gap between the microscopic fingerprints of active sites and the macroscopic catalytic performance.

Synthetic shape-shifting materials typically rely on monotonic evolution between equilibrium states, limiting the shape-shifting behaviours. Here the authors report an unanticipated shape-shifting behaviour for a hydrogel that can be programmed to operate via a far-from-equilibrium mechanism.

Metal/oxide interface is of fundamental significance to heterogeneous catalysis. Here, the authors construct a nanometer Pd/Bi2O3 interface by grafting Pd clusters onto Bi2O3 clusters and demonstrate its essential roles in the low-temperature semi-hydrogenation of acetylene.

Direct dehydrogenation has been a thematic research area resulting from the energy shortage and petroleum gas upgrading scenario. Here, the authors fabricate fully exposed Pt3 clusters and correlate dehydrogenation activity with average coordination number of Pt-Pt bond.

In situ tuning of the electronic structure of active sites is a long-standing challenge. Here, the authors report an approach to tune the electronic structure of cobalt species during the styrene epoxidation reaction by the introduction of controllable hydrogen spillover for enhanced selectivity.

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.

Red phosphorus is a promising anode for Na-ion batteries but suffers from large volume change upon cycling. Here the authors show a red-phosphorus-impregnated carbon nanofiber design in which the sodiated red phosphorus is featured by a “liquid-like” behavior and ultra-stable electrochemical performance is realized.

H2 energy as an alternative to fossil fuels requires cost-effective catalysts with fast kinetics for splitting water. Here, authors design MoS2 materials with di-anionic surfaces to improve the electrocatalytic H2 evolution activities.

Photocatalyst activity depends significantly on the material’s electronic structures. Here, authors manipulate the electron spin polarization of TiO2 by tuning the concentration of Ti vacancies and show improved photocatalytic activities.

Supported noble metal nanoclusters and single-metal-sites catalysts are inclined to aggregate into particles. Here, the authors report a general method with CO and CH3I to disperse the metal nanoparticles of Ru, Rh, Pd, Ag, Ir and Pt completely into single atoms with loading up to 5 wt%.

Monitoring catalyst structural changes under working conditions is crucial for understanding how catalysts operate. Here, authors examine single-atom Ru electrocatalyst by operando synchrotron spectroscopies to identify the catalytic mechanism during the acidic oxygen evolution reaction.

It is highly desired to explore cheap, non-toxic transition metals catalysts for semihydrogenation of acetylene. Here, isolated Cu atoms anchored onto a defective nanodiamond-graphene support exhibit robust catalytic performance in acetylene semihydrogenation in comparison with supported Cu clusters.

CO2 conversion to liquid fuels provides an appealing means to remove the greenhouse gas, although it is challenging to find materials that are both active and selective. Here, authors show sulfur-doped indium to be a highly active and selective electrocatalyst that transforms CO2 into formate.

H2 generated from water electrolysis is a promising, carbon-neutral fuel, but sluggish oxidation kinetics and poor catalyst stability in acid limits the chemistry. Here, authors prepare solid-solution catalysts based on ruthenium-chromium oxides that are stable and active for acidic water oxidation.

Fischer–Tropsch synthesis (FTS) is theoretically limited by Anderson–Schulz–Flory (ASF) law. Here, the authors successfully tune the selectivity of products from diesel-range hydrocarbons to gasoline-range hydrocarbons in FTS by controlling the crystallite sizes of confined cobalt, and modify the ASF law.

While splitting water could provide a renewable way to produce fuel, highly active catalysts are needed to overcome water oxidation’s sluggish kinetics. Here, authors gain atomic-level insight on metal ion synergetic interactions that boost water oxidation performances in co-doped nickel hydroxide.

While water reduction may provide a carbon-neutral means to produce hydrogen gas, there is a scarcity of efficient, earth-abundant electrocatalysts. Here, the authors add palladium into MoS2 materials to activate and stabilize the conductive basal plane to improve the electrocatalytic activity.

Direct transformation of methanol into two- or multi-carbon compounds is extremely attractive but remains a challenge. Here, the authors report an efficient photocatalytic route to the transformation of methanol into ethylene glycol and hydrogen over a molybdenum disulfide nanofoam-modified cadmium sulfide nanorod catalyst.

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.

Nature Communications 8: Article number: 15938 (2017); Published: 24 July 2017; Updated: 27 September 2017. The affiliation details for one of the corresponding authors, Ying Wang, are incorrect in this Article. This author is incorrectly affiliated with ‘University of Chinese Academy of Sciences, Beijing 100049, China.