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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]

In recent years, electrochemical nitrogen reduction reaction (ENRR) has emerged as a promising alternative for ammonia production in a clean and energy-efficient manner. We reported the remarkable performance of a transition metal-based electrocatalyst, Fe(III)(PLY)3 (where PLY-H = 9-hydroxyphenalenone), for electrochemical NRR. In an acidic electrolyte, Fe(PLY)3 catalyst demonstrates remarkable performance, achieving a high faradaic efficiency (FE) of 43.4% and an impressive ammonia (NH3) yield rate of 99.7 μg h−1 mgcat−1 at −0.2 V compared to a reversible hydrogen electrode (RHE). [ABSTRACT FROM AUTHOR]

Electrocatalysis performs a vital role in numerous energy transformation and repository mechanics, including power cells, Electric field‐assisted catalysis, and batteries. It is crucial to investigate new methods to improve electrocatalytic performance if effective and long‐lasting power systems are developed. The modulation of catalytic activity and selectivity by external magnetic fields over electrochemical processes has received a lot of interest lately. How the use of various magnetic fields in electrocatalysis has great promise for building effective and selective catalysts, opening the door for the advancement of sophisticated energy conversion is discussed. Furthermore, the challenges and possibilities of incorporating magnetic fields into electrocatalytic systems and suggestions for future research areas are discussed. [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]

Ammonia (NH3) is regarded as a renewable energy source as well as an important molecule for agricultural applications. The energy‐intensive Haber‐Bosch method produces large amounts of CO2 gas during ammonia production. As an alternative, there has recently been much interest in the electrocatalytic production of NH3 via the electrochemical nitrogen reduction reaction (ENRR) process utilizing renewable energy under ambient condition. Herein, we report a conducting carbon–supported manganese phthalocyanine electrocatalyst as an efficient electrocatalyst for ENRR applications. The MnPc electrocatalyst exhibited the activity with an ammonia production rate of 61.8 μg h−1mg−1cat with Faradaic efficiency (FE) of 31.3% @–0.4 V vs. RHE, respectively, under ambient condition in 0.1 M HCl solution whereas MnPc/C electrocatalyst exhibited an enhanced the productivity with an ammonia yield rate of 127.7 μg h−1mg−1cat with FE of 35.3% @–0.4 V vs. RHE, respectively. The reliability of N origin in ammonia formation is demonstrated by 1H‐NMR experiments and multiple control analysis. These results open the way for the further study of carbon‐supported transition‐metal phthalocyanine compounds for electrochemical nitrogen fixation to NH3. [ABSTRACT FROM AUTHOR]

Recent trends of innovation in high-resolution displays have inspired parallel developments of several types of flat panel technologies that can deliver energy-efficient performance. Among these upcoming technologies, field emission displays (FEDs) have carved a niche owing to their high brightness, low power consumption, large color range, wide viewing angle and short response time. However, poor efficiencies of the Alq3 phosphor create a serious bottleneck in the commercialization of such devices. Herein we have reported an aluminium-quinoline-graphene (Alq3-graphene) composite nanophosphor which exhibits visible emission under low-voltage electron beam excitation. The addition of graphene to the Alq3 matrix facilitates efficient triggering at luminescence centres enabled by local electric field amplification at Alq3-graphene contact points. The idea introduced here opens up a route for improving the cathodoluminescence (CL) intensity of the current nanophosphors and also gives an insight to the splendid possibilities of the Alq3-graphene composite nanophosphor in this quickly developing field. [ABSTRACT FROM AUTHOR]

Rare earth-doped phosphor materials have always remained in focus for excellent luminescence properties. Herein we have synthesized Yb3+ and Er3+-doped BaWO4 nanophosphor via facile hydrothermal method with red and green region emissions by 980 nm excitation. Red and green region emissions were observed due to 4F9/2 → 4I15/2 and 2H11/2/4S3/2 → 4I15/2 transitions, respectively, of Er3+, where Yb3+ acts as a sensitizer. The sample characterization was done using X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Transmission Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS) techniques. The consequences of different concentrations of activator ion (Er3+) in BaWO4: Yb3+, Er3+ were studied from luminescence perspective in detail. The intensity of overall emission varied with altering the power of excitation that influences the photon transfer pathways. It was found that two-photon processes control both red and green emissions in the upconversion process. Decay behavior for both the emission was investigated. Thus, the tunable photoluminescence property suggests its potential in optoelectronic applications. [ABSTRACT FROM AUTHOR]