Single atom catalysts (SACs) possess unique catalytic properties due to low-coordination and unsaturated active sites. However, the demonstrated performance of SACs is limited by low SAC loading, poor metal–support interactions, and nonstable performance. Herein, we report a macromolecule-assisted SAC synthesis approach that enabled us to demonstrate high-density Co single atoms (10.6 wt % Co SAC) in a pyridinic N-rich graphenic network. The highly porous carbon network (surface area of ∼186 m2 g–1) with increased conjugation and vicinal Co site decoration in Co SACs significantly enhanced the electrocatalytic oxygen evolution reaction (OER) in 1 M KOH (η10 at 351 mV; mass activity of 2209 mA mgCo –1 at 1.65 V) with more than 300 h stability. Operando X-ray absorption near-edge structure demonstrates the formation of electron-deficient Co-O coordination intermediates, accelerating OER kinetics. Density functional theory (DFT) calculations reveal the facile electron transfer from cobalt to oxygen species-accelerated OER.

Density functional theory (DFT) computations apply to physics, chemistry, material science, and engineering. In chemical engineering, DFT identifies material structure and properties, and mechanisms for phenomena such as chemical reaction and phase transformation that are otherwise impossible to measure experimentally. Even though its practical application dates back only a decade or two, it is already a standard tool for materials modelling. Many textbooks and articles describe the theoretical basis of DFT, but it remains difficult for researchers to autonomously learn the steps to accurately calculate system properties. Here, we first explain the foundations of DFT in a way accessible to chemical engineers with little background in quantum mechanics or solid‐state physics. Then, we introduce the basics of the computations and, for most of the rest of the article, we show how to derive physical characteristics of interest to chemical engineers: elastic, thermodynamic, and surface properties, electronic structure, and surface and chemical reaction energy. Finally, we highlight some limitations of DFT; since these calculations are approximations to the Schrödinger equation, their accuracy relies on choosing adequate exchange‐correlation functions and basis sets. Since 1991, the number of articles WoS has indexed related to DFT has increased quadratically with respect to time and now numbers 15 000. A bibliometric analysis of the top 10 000 cited articles in 2018 and 2019 classifies them into four clusters: adsorption, graphene, and nanoparticles; ab initio molecular dynamics and crystal structure; electronic structure and optical properties; and total energy calculations and wave basis sets.

Co-electrolysis of CO2 with simple N-species is an appealing route to sustainable fabrication of C-N bond containing products. A prominent challenge in, the area is to promote the C-N coupling step in place of the established CO2 reduction pathways. This can be particularly difficult when relying on solution-based species (e.g., NH3) to intercept intermediates that are continually being reduced on heterogeneous catalyst surfaces. In light of this, we introduce pulsed electrocatalysis as a tool for C-N bond formation. The reaction routes opened through this method involve both partial reduction and partial oxidation of separate reactants on the same catalyst surface in parallel to co-adsorb their activated intermediates proximal to one another. Using the CO2 and NH3 as model reactants, the end result is an enhancement of selectivity and formation rates for C-N bond containing products (urea, formamide, acetamide, methylamine) by factors of 3-20 as compared to static electrolysis in otherwise identical conditions. An array of operando measurements and computational modelling was carried out to pinpoint the key factors behind this performance enhancement. Finally, the oxy-reductive coupling strategy was extended to additional carbon and nitrogen reactants as well as applied to boost electrochemical C-S coupling.

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