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Mixed-metal oxides are generally considered to be the highest-performance catalysts for alkaline water oxidation. Despite significant efforts dedicated to understanding and accelerating their efficiency, most works have been limited investigations of Ni, Co, and Fe oxides, thus overlooking beneficial effects of hetero-anion incorporation. To this end, we report on the development of Co0.5Fe0.5O0.5F1.5 oxyfluoride materials featuring a rutile crystal structure and porous morphology via a scalable and green synthetic route. The catalyst surface, enhanced through electron withdrawing effects imparted by the fluoride ions, give rise to highly effective catalytic sites for electrochemical water oxidation. In particular, their performance across metrics of Tafel slope (27 mV/dec), mass activity (846 A/g at 1.53 V vs. RHE), turnover frequency (21/s at 1.53 V vs. RHE), overpotential (220 mV for 10 mA/cm2), and stability (27 days of continuous operation) largely surpasses most known Co-based catalysts. Mechanistic studies suggest that this performance is driven by a bimolecular, oxygen coupling reaction mechanism through proximal active sites on the catalyst surface, thus enabling a new avenue for achieving accelerated oxygenic electrocatalysis.

Summary The renewable-energy-driven conversion of CO2 is an important means of generating carbon-based fuels and chemicals to power a sustainable society. While most CO2 reduction (CO2R) is carried out in alkaline electrolyte, working in such conditions often leads to spontaneous carbonate formation and, consequently, a low energy balance and CO2 utilization rate. Alternatively, operating in acid alleviates these issues, but achieving selective CO2R in the presence of high proton concentrations has proven to be a challenge over the years. Recently, a host of works have emerged that have demonstrated both a proof of concept and initial design principles for CO2R in acid. As such, this perspective will cover the key initial findings that steer catalysis towards CO2R. After an overview of successful systems, we turn to the future in examining what key questions remain and steps can be taken in this emerging area to bring CO2R in acid toward practical feasibility.

Environmental catalysis has drawn a great deal of attention due to its clean ways to produce useful chemicals or carry out some chemical processes. Photocatalysis and electrocatalysis play important roles in these fields. They can decompose and remove organic pollutants from the aqueous environment, and prepare some fine chemicals. Moreover, they also can carry out some important reactions, such as O2 reduction reaction (ORR), O2 evolution reaction (OER), H2 evolution reaction (HER), CO2 reduction reaction (CO2RR), and N2 fixation (NRR). For catalytic reactions, it is the key to develop high-performance catalysts to meet the demand for targeted reactions. In recent years, two-dimensional (2D) materials have attracted great interest in environmental catalysis due to their unique layered structures, which offer us to make use of their electronic and structural characteristics. Great progress has been made so far, including graphene, black phosphorus, oxides, layered double hydroxides (LDHs), chalcogenides, bismuth-based layered compounds, MXenes, metal organic frameworks (MOFs), covalent organic frameworks (COFs), and others. This content drives us to invite many famous groups in these fields to write the roadmap on two-dimensional nanomaterials for environmental catalysis. We hope that this roadmap can give the useful guidance to researchers in future researches, and provide the research directions.

Enzymes use adaptive catalytic pocket to accelerate catalysis. Recently published in Nature Catalysis, Zhong and coworkers have translated this functionality into a MOF with a Cu-Ni active site in which the Cu-Ni distance changes to stabilize intermediates along the CO2 to CH4 pathway and give rise to exceptional catalytic selectivity.

Summary: With an increasing global emphasis on renewable energy, electrosynthetic technologies stand to play a substantial role in generating the fuels and chemicals that power today’s society. While directions such as water electrolysis and CO2 directions have been heavily researched in the last decade, the scope of electrosynthesis can be greatly expanded to cover the full range of chemical targets that serve as building blocks for materials, pharmaceuticals, fertilizers, and more. To this end, the main challenges lie in the discovery of novel reaction routes and innovative catalytic systems that circumvent conventional limitations of electrocatalysis. Against this backdrop, this perspective will focus on the use of emerging methodologies to pioneer new electrosynthetic reaction systems. In this work, strategies of environmental control, phase change materials, reactant-selective membranes, and mediated approaches are discussed, before touching on the innovative spectroscopic approaches used to probe these systems and wrapping up with a forward-thinking outlook.

Electrocatalysts enable many energy conversion and storage technologies. Tuning the electronic structure of electrocatalytic transition metal oxides and complexes by introducing substitute metals—which possess a different electronegativity than the parent metals—presents a rational strategy for enhancing performance. Kuznetsov et al. show a unifying concept regarding how the inductive effects of substitute metals alter the molecular orbital structure of transition metal oxides and complexes. Such tuning leads to increased battery capacity and higher catalytic activity.

Increasing global demands for energy supply have accelerated fossil fuel consumption, triggering a gradual increase in atmospheric CO2, leading to adverse environmental effects of global warming, desertification and ocean acidification. Thus, reducing carbon emissions to mitigate climate change is an urgent imperative. Among several feasible strategies, electrochemical reduction of CO2 into value-added feedstocks is a promising one since such processes can be integrated with renewable electricity and powered by intermittent energy sources: wind, solar and hydro among others. The efficiency of CO2 reduction reaction (CO2RR) and its resulting economic feasibility strongly depends on the intrinsic properties of catalyst used. Several approaches have been proposed to attain high electrocatalytic performance of heterogenous electrocatalysts by controlling their size, morphology, surface defects, grain boundaries and crystal facets and by coupling with other synergistic components to synthesize nanocomposites, e.g., metallic alloys or metal/carbon-based nanomaterials. This review presents the latest achievements with metal-based nanomaterials for efficient electrochemical CO2 reduction reaction, their mechanism of action, and promising applications in selective conversions valuable chemicals/fuels, including carbon monoxide, formic acid, hydrocarbons and alcohols.