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Electrocatalytic oxidation of chlorine-rich wastewater, a byproduct of chemical production, to chlorine gas is an integral method for reintroducing chlorine atoms back into the chlorine cycle. However, the implementation of dimensionally stable anodes in industrial applications faces significant challenges due to their high cost and lackluster selectivity. To address these issues, we designed three heterojunctions with varying dimensions (D = 2, 1, 0) using hexagonal boron nitride (h-BN) and carbon-based materials such as graphene, nanotubes, and C60. To explore the reactivity of these heterojunctions for the chlorine evolution reaction (CER), we conducted a systematic investigation under three surface coverage concentrations of Cl− (cCl = 1, 2, 3) employing density functional theory (DFT) and machine learning (ML). The results indicate that reducing the catalyst's dimensionality while simultaneously increasing the surface coverage concentration of Cl− can effectively facilitate the CER. Meanwhile, our results highlight that the zero-dimensional catalyst (D = 0), when subjected to a Cl− surface coverage concentration of 3 (cCl = 3), can efficiently catalyze the CER, achieving an impressively low overpotential of 0.0026 V via the Cl* intermediate without necessitating the formation of ClO*. Additionally, the overpotential of the oxygen evolution reaction (OER) is 1.18 V, which promotes the selectivity of Cl2 generation. Our research not only advances the usage of low-dimensional carbon composites in CER electrocatalysis, but also provides valuable insights for designing effective electrocatalysts to treat chlorine-laden wastewater across a broad range of Cl− concentrations. [ABSTRACT FROM AUTHOR]

We report a new Si-decorated carbon nitride (C5N2H2) electrode for the sustainable generation of a hydrogen storage medium, ammonia (NH3), which not only possesses sound electrical conductivity, dynamic stability, and electrochemical activity for the nitric oxide/nitrogen reduction reaction (NORR/NRR), but also provides an option for designing metal-free electrodes. Most importantly, it is found that the charged surface is of great significance to the improved catalytic performance compared to the neutral condition, but this has always been overlooked. Herein, by means of DFT computations, the stubborn chemical bonds of NO and N2 can be entirely activated under an electron density of −2.15 × 10−2 e Å−2 on the Si-C5N2H2 material with an inconsiderable kinetic energy barrier (0.28 eV) along the protonation path. In brief, this finding paves a way for understanding false results by theoretical calculations compared to experiments. [ABSTRACT FROM AUTHOR]

Designing the performance of multi-atom embellished catalysts is an indispensable prerequisite for accelerating the electrochemical nitric oxide reduction reaction (NORR). Common electronic restructuring strategies (doping, alloying, and steric hindrance) are known to have significant effects on the tuning of catalytic activity, but the effect of these strategies on manipulating by which mechanism a reaction proceeds remains unexplored. Herein, by combining density functional theory and machine learning methods, we have successfully identified a promising catalyst candidate, Fe@MoS2, which not only has fine thermodynamic stability, but also strong resistance to electrochemical corrosion under local alloying conditions. More importantly, competing complex electroreduction reaction pathways are guided in the expected direction by taking advantage of the innate steric hindrance of the defective MoS2. To the best of our knowledge, this work may be the first to propose an action that does not require chemical contact to improve the Faraday efficiency of the product by means of controlling the fundamental mechanism, rather than just focusing on the selectivity of competitive responses. [ABSTRACT FROM AUTHOR]

To determine the formation possibility of 2,6‐diamino‐3,5‐dinitropyrazine‐1‐oxide (LLM-105) /ammonium perchlorate (AP) mixed crystal, the dimer configuration of LLM-105/AP was screened. Three possible configurations (LLM-105/AP1, LLM-105/AP2, and LLM-105/AP3) were obtained, and the mixed crystal of LLM-105/AP and AP'/AP crystal were examined. The binding energy (Ebind), electrostatic potential (ESP), and electronic density topology (AIM) of the dimers of LLM-105/AP were evaluated. Then the radial distribution function (RDF) between nitrogen atoms and oxygen atoms specified in LLM-105/AP and the length distribution of trigger bonds was calculated. The results revealed the hydrogen bonds in those configurations of LLM-105/AP. The binding energy of the three configurations corresponded to 29.7363, 20.8283, and 19.2166 kcal·mol−1. The sequence of the electron density ρ(r) at the bond critical point (BCP) was LLM-105/AP1 > LLM-105/AP2 > LLM-105/AP3. The noticeable peaks were observed in LLM-105/AP and AP'/AP at 0.11–0.31 nm. The Lmax values in LLM-105/AP and AP'/AP were 0.1080 nm and 0.1086 nm, respectively. Therefore, it is possible for LLM-105 and AP to form a mixed crystal. The sensitivity of AP decreased with the addition of LLM-105. The zero oxygen balance could be reached at LLM-105: AP mass ratios between 50:50 and 40:60. [ABSTRACT FROM AUTHOR]

Si@SbN, a highly promising visible-light photocatalyst for the NO reduction reaction (NORR), was studied by performing first-principles calculations. A novel design concept of the Si electron configuration applied to metal-free active sites has been explored. This Si-altered SbN enhances chemical NORR activity without taking into account complicated reaction mechanisms, facilitating the development of catalysts.