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Using low and optimized magnetic field along with electric field is a novel strategy to facilitate electrochemical nitrite reduction reaction (NO2RR). Herein, the magnetic field assisted electrocatalytic ammonia synthesis employing spin‐thrusted β‐MnPc at 95 mT magnetic field is explored. The calculated rate of ammonia generation is 16603.4 µg h−1 mgcat−1, which is almost twice that of the nonpolarized manganese phthalocyanine (MnPc) catalyst. Additionally, the Faradaic efficiency (FE) at –0.9 V versus RHE is found to be 92.9%, significantly higher compared to the nonpolarized MnPc catalyst. In presence of external magnetic field, MnPc catalysts provide a better electron transfer channel which results in a lower charge transfer resistance and hence better electrochemical performances. Density functional theory (DFT) result further verifies that magnetic field induced β‐MnPc has a lower potential barrier (0.51 eV) for the protonation of NO* than nonpolarized β‐MnPc (1.08 eV), which confirms the enhanced electrochemical nitrite reduction to ammonia. [ABSTRACT FROM AUTHOR]

The Ostwald process, which is producing HNO3 for commercial use, involves the catalytic oxidation of NH3 and a series of chemical reactions conducted under severe operating conditions. Due to their energy‐intensive nature, these activities play a major role in greenhouse gas emissions and global energy consumption. In response to the urgent requirements of the global energy and environmental sectors, there is an increasingly critical need to develop novel, highly efficient, and environmentally sustainable methods. Herein, CoPc/C3N4 electrocatalyst, integrating CoPc nanotubes with C3N4 nanosheets, is shown. The CoPc/C3N4 electrocatalyst demonstrates yield rate of 871.8 µmol h−1 gcat−1 at 2.2 V, with corresponding Faradaic efficiency (FE) of 46.4% at 2.1 V, which notably surpasses that of CoPc. Through a combination of experimental investigations and density functional theory (DFT) calculations, this study shows that CoPc anchored on C3N4 effectively simplifies the adsorption and activation of chemically inactive nitrogen molecules. The improved catalytic activity for composite system may be the reason of re‐distribution of charges over the CoPc, tuning the valence orbital of Co center due to the presence of 2D layer of C3N4. This mechanism significantly lowers the energy barrier required for critical breaking of inert N2, ultimately leading to a significant improvement in N2 oxidation efficiency. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of nitrate to ammonia (NO3RR) catalyzed by metal organic frameworks (MOFs) is a promising and efficient method for reducing nitrate pollution in water while simultaneously producing a valuable product, ammonia. Herein, we report the 3D nanoarray architecture of the metal organic complex Fe-(tetracyanoquinodimethane)2 Fe(TCNQ)2 as an efficient electrocatalyst that exhibits a high ammonia yield rate of 11 351.6 μg h−1 cm−2 and faradaic efficiency (FE) of 85.2% at −1.1 V vs. RHE and excellent catalytic stability up to 2 days. The excellent catalytic performance is evaluated by ATR-FTIR spectroscopy and a series of control experiments. Density functional-based theoretical calculations are carried out to identify Fe–N4 active sites in metal–organic network structures. This study showcases the advancement of transition metal-based organic frameworks as very effective electrocatalysts for the reduction of nitrate to ammonia (NH3). [ABSTRACT FROM AUTHOR]

Layered two-dimensional (2D) materials demonstrate exceptional performance as supercapacitor electrodes due to their unique intrinsic properties. A hybrid 2D/2D heterostructured electrode material can synergize the individual energy storage features of each of the layered 2D materials. Ti3C2 MXene is an emergent 2D material with enriched energy storage capabilities but suffers from certain vulnerabilities during the charge storage process. Vanadium ditelluride (VTe2) is an interesting yet unexplored layered material within the 2D transition metal dichalcogenide (TMD) family. Owing to the unique structural features, VTe2 showcases certain advantages in energy storage. The formation of the VTe2/Ti3C2 MXene heterostructure for energy storage applications has not been reported until now. Herein, we report a facile and simple hydrothermal synthesis approach to prepare bare VTe2 and the VTe2/MXene heterostructure for supercapacitor applications. The energy storage mechanism in the heterostructure is systematically analyzed. The synergistically induced interplaying effects enhance the specific capacitance of the heterostructure to 250 F g−1 along with excellent durability during long cycle operation. Consequently, an asymmetric system is constructed with VTe2/MXene as the positive electrode and MoS2/MXene as the negative electrode. The 2D/2D heterostructure-based asymmetric supercapacitor delivers excellent performance with an energy density of 46.3 W h kg−1 and a highest power density of 6400 W kg−1. Furthermore, the density functional theory calculations predict that the enhancement of electronic Te 5P states near the Fermi level due to MXene leads to improved performance of the VTe2/Ti3C2 hybrid for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen oxidation reaction (N 2 OR) offers a sustainable alternative to the conventional methods such as the Haber-Bosch and Ostwald oxidation processes for converting nitrogen (N 2 ) into high-value-added nitrate (NO 3 - ) under mild conditions. However, the concurrent oxygen evolution reaction (OER) and inefficient N 2 absorption/activation led to slow N 2 OR kinetics, resulting in low Faradaic efficiencies and NO 3 - yield rates. This study explored oxygen-vacancy induced tin oxide (SnO 2 -O v ) as an efficient N 2 OR electrocatalyst, achieving an impressive Faradaic efficiency (FE) of 54.2% and a notable NO 3 - yield rate (22.05 µg h -1 mg cat -1 ) at 1.7 V versus reversible hydrogen electrode (RHE) in 0.1 m Na 2 SO 4 . Experimental results indicate that SnO 2 -O v possesses substantially more oxygen vacancies than SnO 2 , correlating with enhanced N 2 OR performance. Computational findings suggest that the superior performance of SnO 2 -O v at a relatively low overpotential is due to reduced thermodynamic barrier for the oxidation of *N 2 to *N 2 OH during the rate-determining step, making this step energetically favorable than the oxygen adsorption step for OER. This work demonstrates the feasibility of ambient nitrate synthesis on the soft acidic Sn active site and introduces a new approach for rational catalyst design., (© 2024 Wiley‐VCH GmbH.)

Electrochemical nitrogen reduction reaction (e-NRR) is an eco-friendly alternative approach to generate ammonia under ambient conditions, with very low power supply. But, developing of an efficient catalyst by suppressing parallel hydrogen evolution reaction as well as avoiding the catalysts poisoning either by hydrogen or electrolyte ion is an open question. So, in order to screen the single atom catalysts (SACs) for the e-NRR, we proposed a descriptor-based approach using density functional theory (DFT) based calculations. We investigated total 24 different SACs of types TM-Pc, TM-N 3 C 1 , TM-N 2 C 2 , TM-NC 3 and TM-N 4 , considering transition metal (TM). We have considered mainly BF 3 ion to understand the role of electrolyte and extended the study for four more electrolyte ions, Cl, ClO 4 , SO 4 , OH. Herein, to predict catalytic activity for a given catalyst we have tested 16 different electronic parameters. Out of those, electronic parameter d xz ↓ occupancy, identified as electronic descriptor, is showing an excellent linear correlation with catalytic activity (R 2 =0.86). Furthermore, the selectivity of e-NRR over HER is defined by using an energy parameter ▵G *H -▵G *NNH . Further, the electronic descriptor (d xz ↓ occupancy) can be used to predict promising catalysts for e-NRR, thus reducing the efforts on designing future single atom catalysts (SACs)., (© 2024 Wiley-VCH GmbH.)

The increasing demand for clean hydrogen production over fossil fuels necessitates the development of sustainable piezoelectrochemical methods that can overcome the limitations of conventional electrocatalytic and photocatalytic approaches. In this regard, existing piezocatalysts face challenges related to their low piezoelectricity or active site coverage for hydrogen evolution reaction (HER). Driven by global environmental concerns, there is a compelling push to engineer practical materials for highly efficient HER. Herein, monoelemental 2D tellurium (Te) is presented as a class of layered chalcogenide with a non-centrosymmetric crystal structure (P3 1 21 space group). The refined Te nanosheets demonstrate an unprecedented highly efficient H 2 production rate ≈9000 µmol g -1  h -1 under ultrasonic mechanical vibration due to built-in piezo-potential in the system. The remarkable piezocatalytic performance of Te nanosheets arises from a synergistic interplay between their semi-metallic nature, favorable free energy landscape, enhanced electrical conductivity and outstanding piezoelectricity. As a proof of concept, the theoretical approach based on Density Functional Theory (DFT) validates the findings due to the gradual exposure of active sites on the Te nanosheets leading to a self-optimized catalytic performance for hydrogen generation. Therefore, mechanically driven Te emerges as a promising piezocatalyst with the potential to revolutionize highly efficient and sustainable technology for futuristic applications., (© 2024 Wiley‐VCH GmbH.)