With the continuous development of sustainable and renewable energy, the electrocatalytic water cycle and rechargeable metal-air batteries are attracting increasing attention. As two main reactions, oxygen evolution/reduction reaction (OER/ORR) are...

Herein, utilizing density functional theory (DFT) calculations, we have assessed the feasibility of single-atom-embedded C 3 N with various coordination environments of TM-C 3 , TM-C 2 N 1 , TM-C 4 , and TM-C 2 N 2 for oxygen electrocatalysis. It has been proved that most TM-C x N y candidates are stable and all of them possess metallic features to ensure fast electron transfer. Importantly, Co-C 2 N 2 is a bifunctional noble-free single-atom catalyst with low OER/ORR overpotentials (0.33/0.39 V). Furthermore, the impact of the coordination environment on the adsorption trend is revealed by the electronic properties of TM-C x N y . Considering that TM-d electron counts are multiplied by the sum of TM and C/N electronegativity, we propose a universal descriptor and offer more understanding of the coordination−activity correlation. Our findings not only show promising single-atom-embedded C 3 N candidates for oxygen electrocatalysis but also deeply unveil the impact of the coordination environment on catalytic activity.

Understanding the reaction and deactivation mechanism of CO 2 photoreduction is critical to the carbon-neutral economy. Here, we report a self-poisoning effect in CO 2 photoreduction accompanied by C 2 production. With phosphorus-doping and nitrogen-vacancy engineering, the CO 2 photoreduction reactivity on carbon nitride can be significantly enhanced with a considerable yield of C 2 . Nevertheless, the stability of this catalyst decreases with the enhanced C 2 production. The deactivation originates from the rigid bonding between the catalysts and C 2 products, slowing down the desorption process and poisoning the catalysts. This work demonstrates the opposite role of defect engineering in the activity and stability of CO 2 photoreduction, which may provide insights into a highly reactive and durable C 2 catalyst design.

Nowadays, trifluoromethyl sulfonyl fluoride (CF 3 SO 2 F) has shown great potential to replace SF 6 as an eco-friendly insulation medium in the power industry. In this work, an effective and low-cost design strategy toward ideal gas sensors for the decomposed gas products of CF 3 SO 2 F was proposed. The strategy achieved high-throughput screening from a large candidate space based on first-principle calculation and machine learning (ML). The candidate space is made up of different transition metalembedded graphic carbon nitrides (TM/g-C 3 N 4 ) owing to their high surface area and subtle electronic structure. Four main noteworthy decomposition gases of CF 3 SO 2 F, namely, CF 4 , SO 2 , SO 2 F 2 , and HF, as well as their initial stable structure on TM/g-C 3 N 4 were determined. The best-performing ML model was established and implemented to predict the interaction strength between gas products and TM/g-C 3 N 4 , thus determining the promising gas-sensing materials for target gases with the requirements of interaction strength, recovery time, sensitivity, and selectivity. Further analysis guarantees their stability and reveals the origin of excellent properties as a gas sensor. The high-throughput strategy opens a new avenue of rational and low-cost design principles of desirable gas-sensing materials in an interdisciplinary view.

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