Operating Temperature Research Articles

Defect-Enabled Superior Negative Thermal Quenching in Palmierite Ba9La(VO4)7:Eu3+ for WLED In Situ Temperature Measuring.

Negative thermal quenching (NTQ) of the phosphors is critically important for both scientific research and practical applications, but the design of efficient NTQ phosphors is still a challenging task. Herein, we report a new strategy for developing NTQ materials by cation-vacancy engineering. Specifically, a new color-tunable Ba9La1-x(VO4):xEu3+ (BLVO:xEu3+) phosphor with abundant intrinsic cation vacancy was developed, exhibiting superior NTQ behavior under 365 nm excitation. The NTQ performance can be modulated via adjusting Eu3+ doping levels, and the emission intensity of Eu3+ ions in the BLVO:0.20Eu3+ phosphor increased by 275% at 473 K compared to room temperature. Furthermore, the reported material emitting bright white light under 365 nm excitation was well-suited for use in white light-emitting diode (WLED) phosphor and fluorescent temperature sensors, exhibiting outstanding color-rendering index (90.1) in lighting and high sensitivity (Sa = 11.83% K-1, Sr = 2.33% K-1) in temperature detecting. Lastly, the operating temperature of WLED at different currents can be monitored and displayed in real time through emission spectroscopy. All of the results demonstrated that the designed NTQ BLVO:xEu3+ can be used as a single-phase white phosphor and optical thermometry. This work provides a fresh perspective for designing high-efficient NTQ phosphors and expands the application of phosphors in WLED in situ temperature detection.

Proton exchange membrane‐based electrocatalytic systems for hydrogen production

AbstractHydrogen energy from electrocatalysis driven by sustainable energy has emerged as a solution against the background of carbon neutrality. Proton exchange membrane (PEM)‐based electrocatalytic systems represent a promising technology for hydrogen production, which is equipped to combine efficiently with intermittent electricity from renewable energy sources. In this review, PEM‐based electrocatalytic systems for H2 production are summarized systematically from low to high operating temperature systems. When the operating temperature is below 130°C, the representative device is a PEM water electrolyzer; its core components and respective functions, research status, and design strategies of key materials especially in electrocatalysts are presented and discussed. However, strong acidity, highly oxidative operating conditions, and the sluggish kinetics of the anode reaction of PEM water electrolyzers have limited their further development and shifted our attention to higher operating temperature PEM systems. Increasing the temperature of PEM‐based electrocatalytic systems can cause an increase in current density, accelerate reaction kinetics and gas transport and reduce the ohmic value, activation losses, ΔGH*, and power consumption. Moreover, further increasing the operating temperature (120–300°C) of PEM‐based devices endows various hydrogen carriers (e.g., methanol, ethanol, and ammonia) with electrolysis, offering a new opportunity to produce hydrogen using PEM‐based electrocatalytic systems. Finally, several future directions and prospects for developing PEM‐based electrocatalytic systems for H2 production are proposed through devoting more efforts to the key components of devices and reduction of costs.

Highly Diffusive Nonluminescent Carriers in Hybrid Phase Lead Triiodide Perovskite Nanowires

AbstractCrystal structural rearrangements unavoidably introduce defects into materials, where even these small changes in local lattice structure could arouse a prominent impact on the overall nature of crystals. Contrary to the traditional notion that defects obstruct carrier transport, herein, we report a promoted transport mechanism of nonluminescent carriers in single‐crystalline CH3NH3PbI3 nanowires (1345.2 cm2 V−1 s−1, about a 14‐fold improvement), enabled by the phase transition induced defects (PTIDs). Carriers captured by PTIDs evade both the radiative and non‐radiative recombinations during the incomplete tetragonal‐to‐orthorhombic phase transition at low temperatures, forming a specific nonluminescent state that exhibits an efficient long‐distance transport and thereby realize a prominent enhancement of photocurrent responsivity for photodetector applications. The findings provide broader insights into the carrier transport mechanism in perovskite semiconductors and have significant implications for their rational design for photoelectronic applications at varied operating temperatures.

Highly Diffusive Nonluminescent Carriers in Hybrid Phase Lead Triiodide Perovskite Nanowires.

Crystal structural rearrangements unavoidably introduce defects into materials, where even these small changes in local lattice structure could arouse a prominent impact on the overall nature of crystals. Contrary to the traditional notion that defects obstruct carrier transport, herein, we report a promoted transport mechanism of nonluminescent carriers in single-crystalline CH3NH3PbI3 nanowires (1345.2 cm2 V-1 s-1, about a 14-fold improvement), enabled by the phase transition induced defects (PTIDs). Carriers captured by PTIDs evade both the radiative and non-radiative recombinations during the incomplete tetragonal-to-orthorhombic phase transition at low temperatures, forming a specific nonluminescent state that exhibits an efficient long-distance transport and thereby realize a prominent enhancement of photocurrent responsivity for photodetector applications. The findings provide broader insights into the carrier transport mechanism in perovskite semiconductors and have significant implications for their rational design for photoelectronic applications at varied operating temperatures.

Medium and high temperature H2S removal via phosphazene polyoxometalate ionic liquids: Performance evaluation and mechanism exploration

The development of non-aqueous solvent desulfurizer is crucial to addressing the challenges associated with traditional liquid-phase wet desulfurization technologies. Based on this, we prepared a series of phosphazene polyoxometalate ionic liquids (PPILs) based of 1-butyl-3-methylimidazolium chloride using different kinds of phosphazenes (PNs) combined with polyoxometalate (POM), and used for hydrogen sulfide (H2S) dynamic absorption experiments. The effects of PN type and ratio, temperature and desulfurizer concentration on the desulfurization performance of different PPILs were explored. Among them, PPILs@IBuPN-9 as the optimal desulfurizer could keep almost 100 % desulfurization efficiency in the medium and high temperature range (100–200 °C). The results showed that the combination of PNs with POM significantly improved and widened the H2S removal performance and the operational temperature window of the desulfurizer. Besides, PPILs@IBuPN-9 required only air regeneration to maintain relatively stable cycle performance for at least four times and the sulfur capacity could be efficiently increased during multiple regenerations. It was found that the hydrogen bonding sites on IBuPN network formed significantly enhanced the H2S capture ability of PPILs and the sulfur capacity was substantially improved by S2− substitution of oxygen atoms in the POM according to the characterization results and density functional theory calculations. This study promotes the deep integration of polyoxometalate chemistry with ionic liquids in the field of gas purification and promotes the development of non-aqueous phase desulfurization process.

Application of chaotic teaching-learning-based optimization technique for estimating unknown parameters of proton exchange membrane fuel cell model.

Proton exchange membrane fuel cells (PEMFC) possess features like high specific power density, low operating temperature, and low operating pressure and thus are most widely used. The performance of PEMFC highly depends on its output voltage which further affects its efficiency. This research paper aims to improve this output voltage by minimizing the losses through parameter estimation technique for three well-known commercial PEMFC stacks, namely, 250W, BCS 500W, and Ballard Mark V. The multiobjective function framed for optimization serves two goals. One is to extract the unknown parameters of FC, and second is to achieve the minimum sum of squared errors (SSE) that occur due to the difference between experimental voltage and estimated voltage. Chaotic teaching-learning-based optimization (CTLBO) algorithm is used for optimization process. SSE values obtained for three commercial PEMFC stacks 250W, BCS 500W, and Ballard Mark V are 7.02267, 4.00150, and 0.8100, respectively. The applicability of this technique is further checked for different operating conditions of each model. The I-P (current-power) curve and I-V (current-voltage) curve obtained using estimated data closely matched the experimental data that showed the practical relevance and efficacy of the algorithm. A comparison is done among the SSE results obtained using CTLBO to other competitive algorithms mentioned in the literature. CTLBO showed its superiority over other algorithms in estimating the unknown parameters of PEMFC stack parameters.

Single walled carbon nanotubes/ZnO nanowires heterostructure array for NO2 gas sensing at low ppm levels

A layer-by-layer ZnO nanowire (NW)-Single Walled Carbon Nanotube (CNT) hybrid gas sensor has been proposed for effective detection of NO2 gas under a low exposure limit of 5 ppm. The fabricated hybrid sensor displayed good sensor response (S %), good selectivity and fast response time towards the target gas. S % value of 36.4 % under 5 ppm NO2 level at 250 °C and good selectivity response towards different interfering gases like SO2, CO and H2 have been observed. Meanwhile, fast response time values of 44.08 s (response) and 62.11 s (recovery) were observed at 300 °C under 5 ppm NO2 level. The sensor baseline resistance of the hybrid heterostructure (HS) was also found to be lower when compared to that of a bare ZnO NW sensor. In addition, the presence of Single Walled CNT in the HS was also shown to reduce the operational temperature of the sensor. Temperature played a significant role by controlling the adsorption and desorption kinetics of gas molecules on the surface. Moreover, the formation of p-n interface between Single Walled CNT (p-type) and ZnO NW (n-type) might have modulated the potential charge barrier on interacting with the adsorbed gases which inturn might have impacted the response of the hybrid sensor. In addition, the large surface areas offered by both NWs and nanotubes might have improved the gas adsorption capability thereby enhancing the overall hybrid sensor’s response.

Exploring the Potential of Cold Sintering for Proton-Conducting Ceramics: A Review.

Proton-conducting ceramic materials have emerged as effective candidates for improving the performance of solid oxide cells (SOCs) and electrolyzers (SOEs) at intermediate temperatures. BaCeO3 and BaZrO3 perovskites doped with rare-earth elements such as Y2O3 (BCZY) are well known for their high proton conductivity, low operating temperature, and chemical stability, which lead to SOCs' improved performance. However, the high sintering temperature and extended processing time needed to obtain dense BCZY-type electrolytes (typically > 1350 °C) to be used as SOC electrolytes can cause severe barium evaporation, altering the stoichiometry of the system and consequently reducing the performance of the final device. The cold sintering process (CSP) is a novel sintering technique that allows a drastic reduction in the sintering temperature needed to obtain dense ceramics. Using the CSP, materials can be sintered in a short time using an appropriate amount of a liquid phase at temperatures < 300 °C under a few hundred MPa of uniaxial pressure. For these reasons, cold sintering is considered one of the most promising ways to obtain ceramic proton conductors in mild conditions. This review aims to collect novel insights into the application of the CSP with a focus on BCZY-type materials, highlighting the opportunities and challenges and giving a vision of future trends and perspectives.

Enhanced sensitivity and selectivity of ZnSe/PANI nanocomposite for Low-ppm NO2 detection at room temperature gas sensor application

The utilization of n-p composite-based gas sensors has garnered substantial interest within the field of gas sensing. This heightened attention can be attributed to the remarkable band alignment of the constituent materials which results in superior charge transfer rate, increased gas interaction sites and reduced optimum operating temperature. In this work, n-ZnSe/p-PANI composites were prepared by simple hydrothermal technique. The obtained X-ray diffraction pattern confirms the phase formation ZnSe, PANI and ZnSe/PANI composites. The pure ZnSe exhibits a sensing performance at a higher operating temperature of 100 °C, whereas ZnSe/PANI composite sample demonstrates an improved sensing response at 30 °C. Notably, the 20 wt.% composite sample (ZnSe–P2) achieved a maximum sensing response of 77 % towards 20 ppm of NO2 gas molecule. Additionally, the sensor exhibits the response time (Tres) of 112 s and recovery time (Trec) of 648 s, at an operating temperature of 30 °C. It also shows better stability, reproducibility and specific selectivity towards NO2 gas molecule. The superior sensing behavior of the ZnSe-P2 sensor can be ascribed to the development of a depletion region in the interface of ZnSe/PANI composites, which improved the charge transfer rate and increased the number of reactive sites. Therefore, the formation of n-p inorganic-organic composite strategy offers an effective approach for detecting NO2 gas molecules at lower temperature of 30 °C.

Influence of Mg2+ doping on the oxide ion conductivity of layered ferroelectric SrBi2Ta2O9

Layered perovskites structures are an interesting candidate to explore as a potential electrolyte materials for Solid oxide fuel cell (SOFC) applications. However, achieving a high ionic conductivity (∼0.01 S cm⁻1 below 650 °C) remains a significant challenge to lowering the SOFC operating temperatures. SrBi2Ta2O9 (SBT), an Aurivillius-based layered perovskite, is a well-known ferroelectric material with TC of 320 °C. Site exchange and Bi volatility related defects lead to ionic conductivity in SBT above 700 °C. Here, we aim to control the defect chemistry by doping to promote the oxygen vacancies. We show that Mg doping at the Ta-site in the perovskite block results in 4-fold increase in the bulk conductivity of SBT 3.65 × 10−4 S cm−1 and improvement in the ionic transport number from 0.26 to 0.71. The study provides an opportunity to design new oxide ion conductors in layered ferroelectric oxides.

Antioxidant Sulfide‐Linked Polymer Membrane with Inherent Microporosity Enables Fuel Cells to Achieve Outstanding Power Density and Durability Over a Wide Temperature Range

AbstractConventional phosphoric acid (PA) doped polybenzimidazole are regarded as the most promising materials for high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs). Yet, their practical application has been hindered by their high production cost, poor oxidation stability, and loss of PA at low temperatures. Here, a polymer of intrinsic microporosity containing “sulfide‐linkage” radical‐sacrificial‐agent is designed with good solubility and high PA retention, which enables it to operate for long periods at 80–180 °C. Specifically, the “sulfide‐linkage” radical‐sacrificial‐agent enabled PSBI‐IM to be durable for 100 h with mass retention still higher than 90%, and the capillary effect of the micropores enabled PSBI‐IM/PA to retain more than 60% of PA under high humidity. After rational optimization, the cell assembled with PSBI‐IM/PA achieved a power density of 1.62 W cm−2 with a specific power of 2.7 W mg−1 and an operating time of more than 500 h (0.2/0.4 A cm−2@160 °C). In addition, the voltage drop is only 5% even after 40 h of accelerated stress testing at 0.4 A cm−2@ 80 °C. Therefore, the PSBI‐IM/PA can be stabilized over a wide temperature range from 80 to 160 °C, providing a new material for the HT‐PEMFCs with flexible operational temperature.

Role of Sintering Aids in Electrical and Material Properties of Yttrium- and Cerium-Doped Barium Zirconate Electrolytes

Ceramic proton conductors have the potential to lower the operating temperature of solid oxide cells (SOCs) to the intermediate temperature range of 400–600 °C. This is attributed to their superior ionic conductivity compared to oxide ion conductors under these conditions. However, prominent proton-conducting materials, such as yttrium-doped barium cerates and zirconates with specified compositions like BaCe1−xYxO3−δ (BCY), BaZr1−xYxO3−δ (BZY), and Ba(Ce,Zr)1−yYyO3−δ (BCZY), face significant challenges in achieving dense electrolyte membranes. It is suggested that the incorporation of transition and alkali metal oxides as sintering additives can induce liquid phase sintering (LPS), offering an efficient method to facilitate the densification of these proton-conducting ceramics. However, current research underscores that incorporating these sintering additives may lead to adverse secondary effects on the ionic transport properties of these materials since the concentration and mobility of protonic defects in a perovskite are highly sensitive to symmetry change. Such a drop in ionic conductivity, specifically proton transference, can adversely affect the overall performance of cells. The extent of variation in the proton conductivity of the perovskite BCZY depends on the type and concentration of the sintering aid, the nature of the sintering aid precursors used, the incorporation technique, and the sintering profile. This review provides a synopsis of various potential sintering techniques, explores the influence of diverse sintering additives, and evaluates their effects on the densification, ionic transport, and electrochemical properties of BCZY. We also report the performance of most of these combinations in an actual test environment (fuel cell or electrolysis mode) and comparison with BCZY.

The degradation mechanism of high power S-band AlGaN/GaN HEMTs under high temperature

Abstract The radio frequency (RF) degradation mechanism under high temperature is proposed in this paper. The saturated output power (P sat), power added efficiency (PAE) and gain of the HEMTs deteriorate significantly under high power dissipation operation conditions, which contribute to an elevation of the junction temperature (T j). The high T j causes a negative shift of the threshold voltage and a reduction of electron mobility, as well as enhancing the trapping effects of the devices. As a result, the P sat and PAE of the high-power HEMTs (P sat = 152 W) decreased by 0.76 dB and 8.3%, respectively, which is more severe compared to low-power HEMTs (P sat = 20 W), where P sat and PAE reduced by 0.16 dB and 3.1% when the operation temperature was increased from 25 °C to 150 °C. By increasing the gate-to-drain distance from 1.625 to 2.175 μm, drain current stability and high temperature reverse bias reliability are improved. The results demonstrate that the trapping effect can be suppressed by decreasing the electric field under the gate; therefore, the RF output characteristics are boosted by 1.2 W, 1 dB and 2.6% for a device with gate width of 11.52 mm.

Dynamically Confined Active Silver Nanoclusters with Ultrawide Operating Temperature Window in CO oxidation.

Supported metal nanoclusters are often highly active in many catalytic reactions but less stable particularly under harsh reaction conditions. Here, we demonstrate that this activity-stability trade-off can be efficiently broken through rational design of surrounding microenvironment of the supported nanocatalyst including gas adsorbate overlayer and underneath support surface chemistry. Our studies reveal that chemisorbed oxygen species on Ag surface and surface hydroxyl groups on oxide support, which are dynamically consumed during reaction but sustained by reaction environment (O2 and H2O vapor), drive spontaneous redispersion of Ag particles and stabilization of highly active Ag nanoclusters. Such a dynamic confinement effect from gas-catalyst-support interaction enables the Ag nanoclusters to exhibit complete catalytic oxidation of CO over a wide temperature window of 25 - 500 °C under dry conditions and 200 - 800 °C under wet conditions as well as remarkable stability at 300 °C over 1000 h.

Dynamically Confined Active Silver Nanoclusters with Ultrawide Operating Temperature Window in CO oxidation

Supported metal nanoclusters are often highly active in many catalytic reactions but less stable particularly under harsh reaction conditions. Here, we demonstrate that this activity‐stability trade‐off can be efficiently broken through rational design of surrounding microenvironment of the supported nanocatalyst including gas adsorbate overlayer and underneath support surface chemistry. Our studies reveal that chemisorbed oxygen species on Ag surface and surface hydroxyl groups on oxide support, which are dynamically consumed during reaction but sustained by reaction environment (O2 and H2O vapor), drive spontaneous redispersion of Ag particles and stabilization of highly active Ag nanoclusters. Such a dynamic confinement effect from gas‐catalyst‐support interaction enables the Ag nanoclusters to exhibit complete catalytic oxidation of CO over a wide temperature window of 25 ‐ 500 °C under dry conditions and 200 ‐ 800 °C under wet conditions as well as remarkable stability at 300 °C over 1000 h.

Optimization of Sr3NCl3-based perovskite solar cell performance through the comparison of different electron and hole transport layers

Strontium Nitride Trichloride (Sr3NCl3) is a promising absorber material for solar cells due to its unique structural, electrical, and optical properties. We conducted a thorough investigation to scrutinize the structural, optical, and electronic characteristics and the photovoltaic efficiency of double-heterojunction solar cells utilizing Sr3NCl3 absorbers. Various metals were evaluated for the front and rear contacts to determine the optimal metal-semiconductor interface, with the study determining that silver (Ag) is the most suitable option for the front contact and nickel (Ni) for the back contact. The PV performance of innovative Sr3NCl3 absorber-based cell structures was evaluated with two different Hole Transport Layers (HTLs), MASnBe3 and CBTS, alongside ZnO and WS2 serving as the transition metal dichalcogenide (TMD) Electron Transport Layers (ETLs). This investigation examined a range of factors, such as layer thickness, operational temperature, doping density, defect densities at both the interfaces and within the bulk, carrier generation and recombination rates, quantum efficiency (QE), series versus shunt resistance, absorption coefficient, and current density-voltage (J-V) characteristics, utilizing the SCAPS-1D simulator software. Fine-tuning of both two HTL and ETL revealed that the highest power conversion efficiency (PCE) of 27.34 % with JSC of 19.78 mA/cm2, fill factor (FF) of 88.84 %, and VOC of 1.56 V was achieved with MASnBe3 HTL and ZnO ETL, while the lowest PCE of 25.55 %, with JSC of 19.77 mA/cm2, FF of 89.07 %, and VOC of 1.45 V was obtained for CBTS HTL and WS2 ETL, respectively. These findings highlight the promising potential of Sr3NCl3 absorbers with ZnO as ETL and MASnBe3 as HTL for developing advanced perovskites heterostructure solar cells for enhanced performance in the future.

Full-spectrum solar water decomposition for hydrogen production via a concentrating photovoltaic-thermal power generator-solid oxide electrolysis cell system

This study introduces a novel solar-powered concentrating photovoltaic-thermal power generator-solid oxide electrolysis cell system designed to enhance hydrogen production efficiency by optimizing both electrical and thermal energy utilization. The system incorporates a thermal power generator to convert excess high-temperature thermal energy into electrical energy, addressing energy losses associated with high-temperature water electrolysis. Thermodynamic analysis shows that the integration of the thermal power generator improves energy and exergy efficiencies to 0.60 and 0.52, while lowering the optimal operating temperature to 1173 K. The system’s efficiency is sensitive to the proportion of electrical energy supplied by the thermal power generator, with an optimal range identified between 0.1 and 0.2. Higher temperatures improve hydrogen production and efficiency, but increased voltage negatively impacts thermodynamic efficiency. These findings demonstrate that the proposed system offers substantial improvements over conventional solar hydrogen production methods, making it a promising candidate for sustainable hydrogen production. Further research will focus on system integration, material costs, and scalability for commercial use.

Discovery of a novel binary azeotrope with positive synergistic insulation strength as eco-friendly SF6-alternative

Abstract Sulfur hexafluoride (SF6), as the arc extinguishing and insulating medium, is broadly applied in power equipment. While it is very essential to find an environmentally friendly substitute gas for SF6 due to its strong greenhouse effect. Although there are many potential alternatives, most have relatively high boiling points that cannot meet the minimum operating temperature of the power equipment. In the past, the liquefaction temperature of the mixture was reduced by mixing with buffer gases, such as CO2, N2, or dry air. But this method cannot take the insulation performance requirements of eco-friendly insulating gas into account. Therefore, given the current problems and challenges, a novel approach is presented to exploring new eco-friendly gases by incorporating the azeotropic theory. The liquefaction temperature of the gas mixture can be reduced simultaneously while the insulation strength is increased. In this approach, a theoretical prediction model E-PPR78 was introduced to predict the vapor-liquid equilibrium data and RC318 was found to exhibit azeotrope behavior with HFO-1336mzz(E) at 17%. Furthermore, the predicted vapor-liquid equilibrium data obtained were validated against cyclic-analytical experimental results, affirming the efficacy of the proposed model. Subsequently, to assess its insulation performance, breakdown tests were conducted under both AC and lightning impulse voltages, revealing significant positive synergistic effects in the gas mixture. The possible mechanisms of this positive synergistic effect were also discussed. This study offers an innovative way of tackling high boiling point issues plaguing eco-friendly gases. The findings may also enlighten the design of eco-friendly switchgear that utilizes HFO-1336mzz(E) mixtures to replace traditional SF6 gases.

Facile synthesis of green graphite-based (Ni/Cu/N) MOF composite for a methanol oxidation reaction

Recently, direct methanol fuel cells (DMFCs) have been regarded as the greatest energy-producing owing to their low operating temperature, high production rate of methanol, and low greenhouse gas emission. However, the energy conversion efficiency of the DMFCs is still unsatisfactory due to the slow kinetics of the fuel oxidation reaction. So, an economic electrocatalyst with high efficiency and good stability is still needed. Herein, low-cost nanocomposites of (Ni/Cu/N) MOF and palm pollen-derived G-graphite were prepared with different ratios namely, (1:1), (1:2), and (2:1) through a solvothermal reaction. The nanocomposites were characterized via X-ray diffraction (XRD), Scanning electron Microscopy (SEM), Fourier transform infrared (FTIR), Thermal gravimetric analysis (TGA), and, (Brunauer–Emmett–Teller) technique (BET). Electrodes have been tested as electro-catalysts for methanol-oxidation reaction (MOR) in a basic medium. As revealed from the cyclic voltammetry measurements, all electrodes exhibit a good response to MOR, being the nanocomposite with the ratio between (Ni/Cu/N) MOF and G-graphite (2:1) is the best with an oxidation peak current density of 55 mA/cm2 at a scan rate of 50 mV/s, with an onset potential of 0.35 V, and stability reaches 96 %. The electrochemical impedance spectroscopy (EIS) test showed that the ratio (2:1) has the lowest charge transfer resistance, RCT, of 5.21 Ω which confirms its higher electrochemical activity. This superior performance of the (Ni/Cu/N) MOF and G-graphite (2:1) over other reported MOF-based electrocatalysts is attributed to the synergistic effect of the (Ni/Cu/N) MOF electrocatalyst, wherein Ni and Cu provide redox electrocatalytic active sites for MOR while the G-graphite contributes towards the chemical stability and electrical conductivity of the electrode, respectively. The good activity and stability of the prepared electrodes suggest the potential use of these electrodes as electrocatalysts for MOR in direct methanol fuel cells (DMFCs).This study opens the venue for valorizing the natural wastes derived graphitic material as stable supporting material in Mof based composites electrodes for MOR.

Summary, Future, and Challenges of Fluoride‐Ion Batteries

Due to the limitations of lithium‐ion batteries (LIBs), there is an urgent need to explore alternative energy storage technologies. However, the high‐energy density of fluoride‐ion batteries (FIBs) has attracted widespread attention as a potential successor to LIBs. FIBs are emerging as a low‐cost, safe, and versatile energy storage solution, with a broad operating temperature range. With continuous efforts from researchers, significant progress has been made in the field of FIBs. Nevertheless, compared to traditional batteries, research on FIBs remains limited, and many challenges and unexplored avenues persist. This article elucidates the principles of FIBs, summarizes the materials for both cathodes and anodes, discusses electrolytes, and addresses existing issues. It also outlines future directions and potential applications of FIBs. As it is continued to innovate and explore, FIBs hold promise for revolutionizing energy storage technology, offering enhanced performance, safety, and sustainability.