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The demand for electronic devices that utilize lithium is steadily increasing in this rapidly advancing technological world. Obtaining high‐purity lithium in an environmentally friendly way is challenging by using commercialized methods. Herein, we propose the first fuel cell system for continuous lithium‐ion extraction using a lithium superionic conductor membrane and advanced electrode. The fuel cell system for extracting lithium‐ion has demonstrated a twofold increase in the selectivity of Li+/Na+ while producing electricity. Our data show that the fuel cell with a titania‐coated electrode achieves 95% lithium‐ion purity while generating 10.23 Wh of energy per gram of lithium. Our investigation revealed that using atomic layer deposition improved the electrode's uniformity, stability, and electrocatalytic activity. After 2000 cycles determined by cyclic voltammetry, the electrode preserved its stability. [ABSTRACT FROM AUTHOR]

This study aims to optimize the Pr 2 NiO 4+δ electrode material for increased phase stability at IT-SOFC operating temperatures while maintaining high electrochemical activity. This is achieved by double doping at both Pr and Ni sites. The series of new Pr 1.6 Ca 0.4 Ni 1–y Cu y O 4+δ complex oxides are synthesized by the pyrolysis of the glycerol-nitrate compositions. The resulting materials are extensively studied by room and high-temperature XRD, XPS, TGA, SEM, dilatometry, DC-four probe method, and impedance spectroscopy. The study has registered the formation of the homogeneous complex oxide phases with an orthorhombic structure (Bmab sp. gr.) throughout the dopant concentration range of y = 0.0–0.4. For the Cu-rich samples, an increased Pr4+ content and the presence of Ni2+ and Cu+1 are observed, resulting in a gradual decrease of both the electroconductivity and the absolute oxygen content (δ ∼ 0 at y ≥ 0.2). Nevertheless, the Pr 1.6 Ca 0.4 Ni 1–y Cu y O 4+δ series materials exhibit excellent phase stability and chemical and thermomechanical compatibility with CeO 2 - and BaCe(Zr)O 3 -based electrolytes. Moreover, Cu-doping enhances the electrochemical activity of the electrodes. The polarization resistance of the Pr 1.6 Ca 0.4 Ni 0.8 Cu 0.2 O 4+δ electrode, is in the range of 0.19–0.27 Ω cm2 (at 700 °C) depending on the electrolyte substrate and shows a low dependence on the water content, demonstrating the applicability of the electrode in fuel cells and electrolysis cells based on both oxygen-ion and proton-conducting electrolytes. [Display omitted] • New Pr 1.6 Ca 0.4 Ni 1–y Cu y O 4+δ (y ≤ 0.4) oxides are obtained by glycerol-nitrate pyrolysis. • These oxides exhibit increased phase stability and compatibility with electrolytes. • Double doping maintains satisfactory conductivity level. • Moderate Cu doping enhances electrochemical activity of the electrodes. • Pr 1.6 Ca 0.4 Ni 0.8 Cu 0.2 O 4+δ is a promising candidate for use in IT SOCs. [ABSTRACT FROM AUTHOR]

Microtubular (MT) geometry of solid oxide cells have a number of distinctive properties, such as high volumetric power density, thermocycling stability and fast start-up capability. In this study, we evaluate the performance of the MT cell with LNO-SDC as air electrode under both fuel cell and electrolysis cell mode operation. While working in the fuel cell mode, the maximum power densities of MT cell reached 533, 740 and 792 mW cm−2 at 750, 800 and 850 °C, respectively. Moreover, the MT cell exhibit excellent long-term stability with no critical performance degradation operating at 750 °C. In the electrolysis mode, current density at 800 °C reached value of 780 mA cm−2 under applied voltage of 1.3 V with fuel gas containing 30 % H 2 O. The results on CO 2 electrolysis indicate remarkable efficiency of studied MT cell with current density of 854 mA cm−2 at an applied voltage of 1.5 V. • Microtubular solid oxide cells with LNO-SDC air electrode were fabricated. • Maximum power density reached 792 mW cm−2 in H 2 (3% H 2 O). • Under steam electrolysis condition, current density of 780 mA cm−2 was obtained at 1.3 V with 30 % H 2 O in fuel gas at 800 °C. • MT cell demonstrated great performance under CO 2 electrolysis condition. • Long-term stability is investigated. [ABSTRACT FROM AUTHOR]

Biochar, produced from the thermochemical conversion of biomass waste, has various applications owing to its broad utility and advantageous properties. This study employs a scientometric approach to comprehensively assess the advancements in biochar application from 2022 to 2023. Utilizing 13,357 bibliographic records sourced from the Web of Science Core Collection with the search term "biochar", the analysis focuses on authorship, national contributions, and keyword trends. Findings demonstrate a continual rise in annual publications since 2009, albeit with a moderated growth rate in 2023. China leads in publication outputs, followed by USA and India, with Hailong Wang emerging as a prominent figure in biochar research. Keyword co-occurrence analyses identify key research themes such as biochar's role in climate change mitigation, easing salinity and drought stress, immobilizing toxic metals, degrading organic pollutants, serving as additives in anaerobic digestion, and functioning as electrodes in microbial fuel cells. Among these, biochar's application for global climate change mitigation gains significant attention, while its utilization as electrodes in microbial fuel cells emerges as a promising research frontier, indicating the growing need for sustainable energy sources. The study also outlines critical research gaps and future priorities for enhancing biochar application. Overall, it highlights the diverse applicability of biochar and offers valuable insight into research progression and forthcoming directions in biochar studies. Highlights: Utilization of bibliometric review for keyword analysis. Examination of recent developments in biochar application. The emerging focus on biochar's effectiveness as electrodes in microbial fuel cells (MFCs). Suggested future research directions and priorities for sustainable biochar application. [ABSTRACT FROM AUTHOR]

Carbon‐based materials are extensively used in fuel cell applications due to their crucial role in maintaining high performance. Particularly, carbon black (CB) stands out as a preferred electrode material for fuel cells, owing to its high electrical conductivity and large surface area. This review focuses on the functionalization of CB and its use as a support for Pt‐based catalysts in proton exchange membrane fuel cells. Functionalization strategies include oxidation, covalent functionalization, as well as polymer grafting or impregnation. Various approaches to functionalize the CB surface are discussed that effectively tailor the surface properties of electrodes, leading to improved fuel cell performance. The improvements are seen in enhanced dispersibility of catalyst particles, better ionomer distribution, increased catalyst stability, and reduced carbon corrosion. This review provides an overview of various modifications applied to CB to enhance their structural and electrochemical properties, thereby boosting fuel cell performance. [ABSTRACT FROM AUTHOR]

This work developed new electrocatalysts for direct alcohol oxidation fuel cells (DAFCs) by using graphene and reduced graphene oxides (GO and rGO) as supporting nanomaterials for copper–nickel (CuNi) nanocomposites. The manufacture of CuNi, CuNi-GO, and CuNi-rGO nanocomposites was realized through the adaptation of Hummer's method and hydrothermal techniques, with subsequent analysis using a range of analytical tools. The electrocatalytic behavior of these materials in DAFCs, with methanol and ethanol as the fuels, was scrutinized through various methods, including cyclic voltammetry, linear sweep, chronoamperometry, and electrochemical impedance spectroscopy. This investigation also assessed the stability and charge transfer dynamics. The rGO-based CuNi nanocomposite demonstrated a remarkable performance boost, showing increases of approximately 319.6% for methanol and 252.6% for ethanol oxidation compared to bare CuNi. The integration of silver nanoparticles into the Ag-CuNi-rGO electrode led to a current density surge to 679.3 mA/g, which signifies enhancements of 254.2% and 812.6% relative to the CuNi-rGO and CuNi electrodes, respectively. These enhancements are ascribed to the augmented densities of hot sites and the synergistic interactions within the nanocatalysts. The findings underscore the potential of Ag and rGO as effective supports for CuNi nanocomposites, amplifying their catalytic efficiency in DAFC applications. [ABSTRACT FROM AUTHOR]

This article discusses the practical applications of nanoparticles (NPs) in various fields, such as medicine, cosmetics, catalysis, and environmental protection. The properties of NPs are influenced by their size, shape, and composition, and their use in catalysis can greatly enhance their activity and efficiency. This special issue focuses specifically on the application of NPs in catalysis for environmental protection, including processes such as the oxidation of volatile organic compounds, hydrogen production, CO2 reduction, wastewater treatment, and soot oxidation. The article expresses gratitude towards the reviewers and authors who contributed to the special issue, acknowledging their time and effort in reviewing the papers and appreciating the high-quality research and review papers submitted. [Extracted from the article]

Silicon, silicon‐based and Si‐containing materials are widely used and play different roles in fuel cells. These materials have been used overall in polymer electrolyte membrane fuel cells, but also in solid oxide fuel cells and phosphoric acid fuel cells. The most used Si compounds in fuel cells are SiO2 and SiC. In this work an overview of the use of Si‐based and Si‐containing materials in the membrane electrode assembly of fuel cells is presented. [ABSTRACT FROM AUTHOR]

Ensuring the stable operation of proton exchange membrane fuel cells is conducive to their real-world application. A promising direction for stabilizing electrodes is the stabilization of the ionomer via the formation of surface compounds with graphene. A comprehensive study of the (electrochemical, chemical, and thermal) stability of composites for fuel cell electrodes containing a modifying additive of few-layer graphene was carried out. Electrochemical stability was studied by cycling the potential on a disk electrode for 5000 cycles. Chemical stability was assessed via the resistance of the composites to H2O2 treatment using ion-selective potentiometry. Thermal stability was studied using differential thermal analysis. Composites were characterized by UV-Vis spectroscopy, Raman spectroscopy, EDX, and SEM. It was shown that graphene inhibits Nafion degradation when exposed to heat. Contrariwise, Nafion is corrosive to graphene. During electrochemical and chemical exposure, the determining change for carbon-rich composites is the carbon loss (oxidation) of the carbon material. In the case of carbon-poor composites, the removal of fluorine and sulfur from the Nafion polymer with their partial replacement by oxygen prevails. In all cases, the F/S ratio is stable. The dispersity of Nafion in a sample affects its chemical stability more than the G/Nafion ratio does. [ABSTRACT FROM AUTHOR]

This study confirmed the efficacy of modified electrode microbial fuel cells (MFCs) in removing chemical oxygen demand (COD) and generating electricity using wastewater from industrial meat processing. The findings of linear sweep voltammetry (LSV) and cyclic voltammetry (CV) demonstrated that applying CuO particles to carbon cloth (CC) significantly reduced the charge transfer resistance, resulting in improved electrochemical performance. In the batch experiment, the MFCs were conducted by applying different electrodes and Nafion‐117 as a proton exchange membrane (PEM). X‐ray powder diffraction (XRD), energy‐dispersive X‐ray analysis (EDAX) and scanning electron microscope (SEM) analyses were performed to study the development of metal oxide on the electrode surface. The MFC operating with the CC/CuO electrode achieved a maximum COD removal (74.6%), which was attained at the peak power output of 82.56 mW/m2 and the greatest current density of 213.33 mA/m2, as indicated by the polarization curve data. In light of these findings, coating CuO on the CC anode promotes electron transfer, enhances the electrode's conductivity and increases its electrochemical surface area. In summary, the findings of this study hold significant implications for sustainable electricity production and remarkable effects on environmental quality, highlighting the strategic importance of the research approach and outputs in addressing global energy and environmental challenges. Highlights: The application of TiO2 and CuO on carbon cloth (CC) as an anode for MFC was reported.The composites as anode materials were studied for the first time.Excellent electrochemical properties were measured to gain maximum COD removal.The CC/CuO composite electrode had a high power density (82.56 mW/m2). [ABSTRACT FROM AUTHOR]

With the increasing consumption of fossil fuels, there is an urgent need to develop a new green and clean energy source. Fuel cells have been extensively studied as a clean alternative to fossil fuels. As a green energy source, direct methanol fuel cells (DMFCs) have high energy density; however, their commercialization is restricted by the poor stability and slow kinetics of methanol oxidation reactions (MORs). One of the key strategies to overcome these problems is to develop efficient, economic and green catalysts for energy storage and conversion devices. Thus far, Pt-based electrocatalysts have been extensively used to enhance the oxidation process of CH3OH. However, since Pt-based electrocatalysts are limited by high cost and susceptibility to CO poisoning, researchers have been motivated to search for a cost-effective, highly active and durable catalytic material. In recent years, Co-based spinel oxides have been found to exhibit good potential as fuel cell electrode materials, they can be modified by defect engineering, alloying and heteroatom doping, or more active sites can be exposed by morphology regulation or carrier regulation, so as to improve their electrocatalytic performance. This review provides a comprehensive introduction to the recent development of Co-based spinel electrocatalysts for emerging MORs involved in DMFCs, and the future development of low-cost and high-performance Co-based spinel oxide catalytic materials is prospected. [ABSTRACT FROM AUTHOR]

Designing an electrocatalyst with low Pt content is an immediate need for essential reactions in low temperature fuel cell systems. In the present work, La0.9925Ba0.0075Al0.995Pt0.005O3 is aimed at using with low (only 0.5%) Pt doping as an electrocatalyst for oxygen reduction reaction (ORR). The low doping level renders exsolution of 1–2 nm nanoparticles with uniform dispersion upon reduction in H2/N2 at low temperatures. Pt exsolved perovskite oxides deliver significantly enhanced catalytic activity for ORR and improved stability in alkaline media. This study demonstrates that LaAlO3 with low noble metal content holds immense potential as an electrocatalyst in real fuel cell systems. [ABSTRACT FROM AUTHOR]

Water pollutants harm ecosystems and degrade water quality. At the same time, many pollutants carry potentially valuable chemical energy, measured by chemical oxygen demand (COD). This study highlights the potential for energy harvesting during remediation using photocatalytic fuel cells (PCFCs), stressing the importance of economically viable and sustainable materials. To achieve this, this research explores alternatives to platinum cathodes in photocathodes and aims to develop durable, cost-effective photoanode materials. Here, zinc oxide nanorods of high density are fabricated on carbon fiber surfaces using a low-temperature aqueous chemical growth method that is simple, cost-efficient, and readily scalable. Alternatives to the Pt cathodes frequently used in PCFC research are explored in comparison with screen-printed PEDOT:PSS cathodes. The fabricated ZnO/carbon anode (1.5 × 2 cm2) is used to remove the model pollutant used here and salicylic acid from water (30 mL, 70 μM) is placed under simulated sunlight (0.225 Sun). It was observed that salicylic acid was degraded by 23 ±0.46% at open voltage (OV) and 43.2 ± 0.86% at 1 V with Pt as the counter electrode, degradation was 18.5 ± 0.37% at open voltage (OV) and 44.1 ± 0.88% at 1 V, while PEDOT:PSS was used as the counter electrode over 120 min. This shows that the PEDOT:PSS exhibits an excellent performance with the full potential to provide low-environmental-impact electrodes for PCFCs. [ABSTRACT FROM AUTHOR]

Reversible solid oxide cells (RSOCs) hold enormous potential for efficient direct CO2 reduction or CO oxidation in terms of exceptional faradic efficiency and high reaction kinetics. The identification of an active fuel electrode is highly desirable for enhancing the performance of RSOCs. This study explores the use of a alkaline metal dopant (Na) to modify the perovskite oxide of Na2x(La0.6−xSr0.4−x)FeO3−δ (2x = 0, 0.10, 0.20) materials with powerful CO2 chemical adsorption capacity, high oxygen ion conductivity, and low average valence of Fe sites for CO2/CO redox reactions. The experimental results indicate that the cells with the NaLSF0.10 fuel electrode achieve a current density of 1.707 A cm−2 at 1.5 V/800 °C and excellent stability over 120 hours at 750 °C for pure CO2 electrolysis, approximately 33.4% improvement over the pristine sample. When operated under a mixed CO–CO2 atmosphere under RSOC mode, the cell outputs the performance of 1.589 A cm−2 at 1.5 V and 329 mW cm−2 at 800 °C, and demonstrates relatively durable operation over 25 cycles. The addition of low valence sodium ions with high basicity and low electronegativity reduces the oxygen vacancy formation energy, increases the concentration of oxygen vacancies and modifies the electronic structure of LSF, thus enhancing CO2 adsorption, dissociation processes and charge transfer steps as corroborated by the detailed experimental analysis. Combined with the acceptable anti-carbon deposition capability, we prove here a feasible strategy and provide new insights into designing novel electrodes for SOEC/RSOCs to effectively convert CO2 with potential for renewable energy storage. [ABSTRACT FROM AUTHOR]

Fe‐N‐C catalysts are a promising alternative to replace cost‐intensive Pt‐based catalysts in high temperature polymer electrolyte membrane fuel cell (HT‐PEMFC) electrodes. However, the electrode fabrication needs to be adapted for this new class of catalysts. In this study, gas diffusion electrodes (GDEs) are fabricated using a commercial Fe‐N‐C catalyst and different polytetrafluorethylene (PTFE) binder ratios, varying from 10 to 50 wt % in the catalyst layer (CL). The oxygen reduction reaction performance is investigated under HT‐PEMFC conditions (160 °C, conc. H3PO4 electrolyte) in a half‐cell setup. The acidophilic character of the Fe‐N‐C catalyst leads to intrusion of phosphoric acid electrolyte into the CL. The strength of the acid penetration depends on the PTFE content, which is visible via the contact angles. The 10 wt % PTFE GDE is less capable to withdraw product water and electrolyte and results into the lowest half‐cell performance. Higher PTFE contents counterbalance the acid drag into the CL and impede flooding. The power density at around 130 mA mgCatalyst−2 increases by 34 % from 10 to 50 wt % PTFE. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) are considered promising energy sources whereby chemical energy is converted into electricity via bioelectrochemical reactions utilizing microorganisms. Several factors affect MFC performance, including cathodic reduction of oxygen, electrode materials, cell internal and external resistances, and cell design. This work describes the effect of the catalyst coating in the air-cathode membrane electrode assembly (MEA) for a microbial fuel cell (MFC) prepared via electrodeposition of manganese oxide. The characterization of the synthesized air-cathode MFC, operating in a continuous mode, was made via electrochemical impedance spectroscopy (EIS) analyses for the determination of the intrinsic properties of the electrode that are crucial for scalability purposes. EIS analysis of the MFCs and of the MEA reveals that the anode and cathode contribute to polarization resistance by about 85% and 15%, respectively, confirming the high catalytic activity of the Mn-based air cathode. The maximum power density of the Mn-based cathode is about 20% higher than that recorded using a Pt/C electrode. [ABSTRACT FROM AUTHOR]

Sr 2 Fe 2-x Mo x O 6-δ -Ce 0.8 Sm 0.2 O 1.9 (SFM-SDC) is a promising composite oxygen electrode for reversible solid oxide cells. In this study, well-dispersed Pt nanoparticles are prepared by one-cycle infiltration method using H 2 PtCl 6 aqueous solution in SFM-SDC scaffold, to form high electrocatalytic activity Pt-SFM-SDC electrode for fuel cell, steam electrolysis and CH 4 -assisted steam electrolysis processes. Systematic studies in concentration variation of H 2 PtCl 6 solution demonstrate that the discharge current of the 3.14 cm2 cell infiltrated by 0.040 M solution is significantly increased from 0.4 to 1.32 A (>3 times) at 0.5 V at 800 °C while the electrolysis current is effectively enhanced from 0.8 to 3.28 A (>4 times) at 1.5 V. Moreover, cells with Pt-SFM-SDC electrode applied in CH 4 -assisted electrolysis process realized a remarkable reduction of power consumption. Impedance analysis and morphological observation results suggest that appropriate H 2 PtCl 6 concentration has a positive effect on surface exchange and gas diffusion process at oxygen electrode side. [Display omitted] • One cycle Pt infiltration method with H 2 PtCl 6 solution is proposed. • The effect of H 2 PtCl 6 solution concentration is investigated. • Pt nanoparticles enhance the electroactivities of SFM-SDC electrode simultaneously toward ORR, OER and POM reactions. [ABSTRACT FROM AUTHOR]

A novel conductive composite based on PEDOT:PSS, BSA, and Nafion for effective immobilization of acetic acid bacteria on graphite electrodes as part of biosensors and microbial fuel cells has been proposed. It is shown that individual components in the composite do not have a significant negative effect on the catalytic activity of microorganisms during prolonged contact. The values of heterogeneous electron transport constants in the presence of two types of water-soluble mediators were calculated. The use of the composite as part of a microbial biosensor resulted in an electrode operating for more than 140 days. Additional modification of carbon electrodes with nanomaterial allowed to increase the sensitivity to glucose from 1.48 to 2.81 μA × mM−1 × cm−2 without affecting the affinity of bacterial enzyme complexes to the substrate. Cells in the presented composite, as part of a microbial fuel cell based on electrodes from thermally expanded graphite, retained the ability to generate electricity for more than 120 days using glucose solution as well as vegetable extract solutions as carbon sources. The obtained data expand the understanding of the composition of possible matrices for the immobilization of Gluconobacter bacteria and may be useful in the development of biosensors and biofuel cells. [ABSTRACT FROM AUTHOR]

This review paper delves into the diverse ways in which carbonaceous resources, sourced from renewable and sustainable origins, can be used in catalytic processes. Renewable carbonaceous materials that come from biomass-derived and waste feedstocks are key to developing more sustainable processes by replacing traditional carbon-based materials. By examining the potential of these renewable carbonaceous materials, this review aims to shed light on their significance in fostering environmentally conscious and sustainable practices within the realm of catalysis. The more important applications identified are biofuel production, tar removal, chemical production, photocatalytic systems, microbial fuel cell electrodes, and oxidation applications. Regarding biofuel production, biochar-supported catalysts have proved to be able to achieve biodiesel production with yields exceeding 70%. Furthermore, hydrochars and activated carbons derived from diverse biomass sources have demonstrated significant tar removal efficiency. For instance, rice husk char exhibited an increased BET surface area from 2.2 m2/g to 141 m2/g after pyrolysis at 600 °C, showcasing its effectiveness in adsorbing phenol and light aromatic hydrocarbons. Concerning chemical production and the oxidation of alcohols, the influence of biochar quantity and pre-calcination temperature on catalytic performance has been proven, achieving selectivity toward benzaldehyde exceeding 70%. [ABSTRACT FROM AUTHOR]

Developing fuel electrodes with excellent structural stability and high catalytic activity under various fuel conditions is highly desirable for large-scale applications of solid oxide cells (SOCs). In this study, double perovskite Sr 2- x FeTaO 6-δ (x = 0, 0.1, 0.2, 0.3) materials were designed as fuel electrodes for SOCs. Sr 1.8 FeTaO 6-δ (S18FT) was synthesized in air, and its structural stability could be maintained in both 5 % H 2 /Ar and pure CO 2 after calcination at 850 ℃ for 10 h. The thermal expansion coefficient of S18FT was 11.8 × 10−6 K−1 at 50–850 ℃. To further improve the electrochemical performance of the S18FT electrode, it was impregnated with Pd(NO 3) 2 to form a composite electrode (Pd-SFT–SDC). When hydrogen, propane, ethyl ethanol, and biochar were used as fuels, the maximum power densities of the fuel cells at 850 ℃ were 1114, 370, 474, and 291 mW cm−2, respectively. The fuel cell operated stably for 300 h when using propane. When the solid oxide electrolysis cell mode was used for the co-electrolysis of CO 2 /H 2 O, the current density was −0.835 A cm−2 at 1.3 V and 800 ℃. These results indicated the potential for the use of the Pd-SFT–SDC composite material as a fuel electrode for SOCs. • Sr 1.8 FeTaO 6-δ (S18FT) has good structural stability in air, H 2 and pure CO 2. • The stability test demonstrates the satisfied structure stability and electrochemical ability of S18FT. • The fuel cell with S18FT fuel electrode shows good electrochemical performance and stability in hydrogen, propane, ethyl ethanol, and biochar. [ABSTRACT FROM AUTHOR]

A 3D structural model for fuel cell catalysis systems is constructed, which consist primarily of Pt and CeO2 nanoparticles, to fit observed small angle X‐ray scattering (SAXS) patterns by using the reverse Monte–Carlo (RMC) method. The observed SAXS patterns are well reproduced by those of the simulations. Pore size distributions using the obtained structure models are compared with the Barrett–Joyner–Halenda (BJH) analysis for the nitrogen gas adsorption data, and the lower quartiles and medians of the pore diameters are reasonably consistent. In addition, analysis of the SAXS patterns indicates that the number of nanometer‐size Pt particles is much smaller than that of the introduced amount. This suggests that most Pt particles are not uniformly distributed in the catalysis system. [ABSTRACT FROM AUTHOR]

Using the method of the joint crystallization of solutions of nitrate salts with ultrasonic treatment, xerogels and highly dispersed mesoporous powders of the following composition are synthesized: (CeO2)1 – x(Nd2O3)x (x = 0.02; 0.05; 0.10), Gd1 – xSrxCo0.5O3 – δ (x = 0.1, 0.15, 0.2, 0, 25), Gd0.4Sr0.1Ni0.5O3 – δ, and Gd0.125La0.125Sr0.25Co0.5O3 – δ; and based on them, nanoceramic materials with a crystalline cubic structure of the fluorite type, as well as an orthorhombic and tetragonal structure of the perovskite type with CSR ~ 55–90 nm (1300°С), respectively, are obtained. The physicochemical properties of the resulting ceramics are studied; it is revealed that it has an open porosity of 7–11% for the composition (CeO2)1 – x(Nd2O3)x and 17–42% for materials with the Gd1 – xSrxCo0.5O3 – δ, Gd0.4Sr0.1Ni0.5O3 – δ, and Gd0.125La0.125Sr0.25Co0.5O3 – δ composition. Materials based on cerium oxide predominantly have the ionic (ion transport numbers ti = 0.71–0.89 in the range 300–700°С) type of electrical conductivity due to the formation of mobile oxygen vacancies in the heterovalent substitution of Ce4+ by Nd3+; and σ700°С = 0.31 × 10–2 S/cm Solid solutions based on nickelate and lanthanum cobaltite have mixed electron-ionic conductivity, σ700°С = 0.59 × 10–1 S/cm with transfer numbers te = 0.92–0.99 and ti = 0.08–0.01. The prospects for using the obtained ceramic materials as solid oxide electrolytes and electrodes for medium-temperature fuel cells (FCs) are shown. [ABSTRACT FROM AUTHOR]

To meet the required useful life targets of proton exchange membrane fuel cells (PEMFC) for long haul and heavy-duty applications, the degradation mechanisms and influences from production need to be analyzed and reduced. Therefore, new and aged PEMFCs should be examined on a macro- and microscopic scale. The purpose of this work is to analyze fuel cells from series production and compare the findings with literature. Since most of the results from literature base on laboratory cells, this research closes the gap between lab-scale experiments and large-scale production. Thereto, the bipolar plates and membrane electrode assemblies of the fuel cells of the Toyota Mirai II and the Hyundai Nexo fuel cell vehicles were examined using optical and scanning electron microscopes. Additionally, energy-dispersive X-ray spectroscopy was performed. Differences in flow fields (channel dimensions, water management), layer and membrane thicknesses, surface porosities, contact angels and layer surface conditions were investigated. Comparisons with current literature provide an opportunity to estimate the influences of the observed structures. In addition, a methodology is developed to map temperatures that result in the discoloration of the titanium bipolar plates during abusive operation. [Display omitted] • Ex-Situ preparation of MEA and BPP of fuel cells from Toyota Mirai II and Hyundai Nexo. • Measurement of layer thickness and contact angles by optical microscopy. • Cracks found by surface analyses facilitate estimations of operating conditions. • SEM-EDX analyses show materials and distribution across a cell of Toyota Mirai II. • Post-mortem analyses of bipolar plate with thermal discoloration after abuse testing. [ABSTRACT FROM AUTHOR]

[Display omitted] Nitrogen-doped carbon-based electrodes are among the most promising alternatives to platinum-based electrodes in the cathode of fuel cells and metal-air batteries, where the oxygen reduction reaction (ORR) takes place. Among the approaches for improving ORR activity, nitrogen functionalities and well-developed textural properties have proved very effective. Nonetheless, the question of which between nitrogen active sites or textural properties are more crucial in N -doped carbon materials remains unanswered. This work proposes a comparative and critical approach through the selective functionalization of four commercial activated carbons with different textural properties. This study highlights the greater importance of N -doping in relation to the textural properties of carbon materials, and provides fundamental insights for conclusively addressing the ongoing debate within the carbon community about the significance of these two factors in the context of ORR. [ABSTRACT FROM AUTHOR]

A citrate–nitrate synthesis of individual materials La0.9Sr0.1Sc1 –xCoxO3 – δ and La0.9Sr0.1CoO3 – δ and their based composites is performed. Composite materials are obtained by solid-phase mixing in different percentages of individual phases, followed by pressing and sintering. The obtained individual and composite materials are explored by X-ray phase analysis and dilatometry. The electrical conductivity of the obtained samples is studied by a direct-current four-probe method depending on the temperature and the gas phase composition. Unique studies of the ability of composites to the ammonia direct decomposition directly at the electrode layer of the fuel cell are carried out. [ABSTRACT FROM AUTHOR]

Ionomeric binders in catalyst layers, abbreviated as ionomers, play an essential role in the performance of polymer–electrolyte membrane fuel cells and electrolyzers. Due to environmental issues associated with perfluoroalkyl substances, alternative hydrocarbon ionomers have drawn substantial attention over the past few years. This review surveys literature to discuss ionomer requirements for the electrodes of fuel cells and electrolyzers, highlighting design principles of hydrocarbon ionomers to guide the development of advanced hydrocarbon ionomers. [ABSTRACT FROM AUTHOR]

Environmental destruction, water crisis, and clean energy are among the very important challenges worldwide based on sustainable development goals. Photocatalytic fuel cell, a potential candidate for converting chemical energy into electrical energy through a pollution-free method, holds promise in addressing these challenges. In this regard, we investigated the response of a photoanode covered with UiO66-NH2-TiO2/NiF on a porous nickel foam as an attractive electrochemical response to remove antibiotics from aqueous solution and simultaneously produce electricity using a one-step hydrothermal synthesis. Nickel foam with its fine structure provides a suitable space for the interaction of light, catalyst, and efficient mass transfer of reactive molecules. It appears that it can be used as a competitive electrode in fuel cells. In order to investigate the properties of the photocatalyst, structural analyses including XRD, FESEM, FTIR, and UV–vis DRS were utilized. Additionally, polarization and electrochemical tests such as chronoamperometry and EIS were measured to further examine the electrochemical features of the PFC photoanode system. The obtained results under optimal conditions (SMZ concentration = 20 ppm, pH = 6, irradiation time = 120 min) were as follows: removal efficiency of 91.7%, Pmax = 16.98 μW/cm2, Jsc = 96.75 μA/cm2, Voc = 644 mV. The light-induced current flow in UiO66-NH2-TiO2/NiF exhibited prominent and reproducible photocurrent responses, indicating efficient and stable charge separation in TiO2/NiF composite materials, which is a promising strategy for pollutant removal and simultaneous electricity generation. [ABSTRACT FROM AUTHOR]

Energy and environmental issues are of great importance in the present era. The transition to renewable energy sources necessitates technological, political, and behavioral transformations. Hydrogen is a promising solution, and many countries are investing in the hydrogen economy. Global demand for hydrogen is expected to reach 120 million tonnes by 2024. The incorporation of hydrogen for efficient energy transport and storage and its integration into the transport sector are crucial measures. However, to fully develop a hydrogen-based economy, the sustainability and safety of hydrogen in all its applications must be ensured. This work describes and compares different technologies for hydrogen production, storage, and utilization (especially in fuel cell applications), with focus on the research activities under study at SaRAH group of the University of Naples Federico II. More precisely, the focus is on the production of hydrogen from bio-alcohols and its storage in formate solutions produced from renewable sources such as biomass or carbon dioxide. In addition, the use of materials inspired by nature, including biowaste, as feedstock to produce porous electrodes for fuel cell applications is presented. We hope that this review can be useful to stimulate more focused and fruitful research in this area and that it can open new avenues for the development of sustainable hydrogen technologies. [ABSTRACT FROM AUTHOR]

Methanogens are used as catalysts for cathodes in microbial fuel cells, to reduce CO2 to CH4. However, the attachment of microbes to the electrodes via culturing is time‐consuming, and inadequate biofilm formation can lead to lesser surface area coverage, resulting in reduced methane formation. This study aims to improve the production efficiency and performance of methanogen cathodes developed using 3D printing of bioink containing live methanogens. A progressive cavity pump is used for the 3D gel‐printing of methanogens and micro‐sized white charcoal particles into the desired structure. Despite the absence of anaerobic conditions during printing, the 3D‐printed cathodes with higher concentrations of microbial inoculum in the bioink produce more methane gas. Even with an unconcentrated inoculum, the methanogens multiply 800‐fold during incubation, resulting in increased methane gas production. The predominant methanogens in the electrodes included the hydrogenotrophic Methanobacterium spp. Therefore, the technique used in this study can be used to successfully develop 3D‐printed biocathodes catalyzed by methanogenic microbes with verifiable practical applicability. This study is the first to report the growth of methanogens and their methanogenic activity in 3D‐printed cathodes. [ABSTRACT FROM AUTHOR]

Strontium segregation (coupled to phase decomposition and impurity poisoning) and electrode delamination are two of the most important degradation mechanisms currently limiting the long‐term stability of solid oxide fuel cell and electrolysis cell (SOFC and SOEC) air electrodes. The present study aims to demonstrate that air electrodes made of entropy‐stabilized multi‐component oxides can mitigate these degradation mechanisms while providing excellent cell performance. A SOEC utilizing La0.2Pr0.2Nd0.2Sm0.2Sr0.2CoO3‐δ (LPNSSC) as an air electrode delivers −1.56 A/cm2 at 1.2 V at 800°C. This performance exceeds that of a commercial cell with La0.6Sr0.4CoO3‐δ (LSC) air electrode, which reaches −1.43 A/cm2. In a long‐term electrolysis test, the LPNSSC cell shows stable performance during 700 h, while the LSC cell degrades continuously. Post‐mortem analyses by scanning electron microscopy‐energy dispersive X‐ray spectroscopy indicate complete delamination of the LSC electrode, while LPNSSC shows excellent adhesion. The amount of secondary phases formed (esp. SrSO4) is also much lower in LPNSSC compared to LSC. In conclusion, the high‐entropy perovskite LPNSSC is a promising option for air electrodes of solid oxide cells. While LPNSSC can compete with ‒ or even outperform ‒ LSC air electrodes in terms of electrochemical performance, it could be particularly advantageous in terms of long‐term stability in SOEC mode. [ABSTRACT FROM AUTHOR]

In this study, a commercial, nonporous carbon black was used as catalyst support for the dispersion of platinum (Pt) nanoparticles (NPs) in a polymer electrolyte membrane (PEM) fuel cell. The microstructure of nonporous carbon black was determined by Brunauer-Emmett-Teller analysis and crystal structure by x-ray diffraction (XRD) analysis. The surface area of carbon black is 72.6 m²/g, and the micropore volume has low fraction in the total volume. The fact that the d(002) value determined according to XRD analysis is 0.377 nm indicates the amorphous structure of nonporous carbon. Inductively coupled plasma mass spectrometry (ICP-MS) analysis determined the Pt loading on nonporous carbon as 15 wt.%. Catalyst support was also investigated electrochemically by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). In CV analysis, as the scan rate increases, capacitive property increases. Furthermore, the low current density of the quinone-hydroquinone (Q-HQ) redox peak suggests nonporous carbon black's corrosion resistance. Nonporous carbon black, whose charge transfer resistance is 454.5 Ω based on EIS analysis, facilitates the mass transfer of species due to its low porosity. Nonporous carbon is preferred to alleviate the water flooding that occurs at the cathode electrode of PEM fuel cells. Platinum NPs supported with nonporous carbon provided 15 and 40 mW/cm² maximum power densities in PEM fuel cell performance tests at 60°C and 70°C, respectively. As the sustainable energy conversion technology of the future, PEM fuel cells can produce enough power to operate everything from mW-scale portable applications to kW-MW-scale transportation and residential uses. In this study, the performance of the nonporous carbon-supported Pt catalyst can be suitable for mW scale applications. [ABSTRACT FROM AUTHOR]

A new type of metal-free oxygen electrode has been proposed. Its distinguishing feature is applying as an active layer nanodispersed graphitic carbon nitride with electrocatalytic properties controlled by synthesis conditions. Optimal conditions of thermochemical synthesis of g-C3N4 by a heat treatment of a solid mixture of melamine precursor and nitrogen-rich urea additive have been defined. The obtained layered g-C3N4 has been characterized by XRD, selected area electron diffraction, TEM and FTIR. An investigation of the electrocatalytic characteristics of oxygen electrodes has been carried out in a fuel half-cell with alkaline electrolyte. The electrochemical characteristics of the obtained g-C3N4 material with melamine-to-urea ratio 1:2 have been shown to be close to those of platinum electrodes. Electrochemical studies have shown that the obtained carbon nitride is a promising material as metal-free catalyst for oxygen electrodes of fuel cells The long-term testing of produced materials confirmed that they were stable over six months. Layered g-C3N4 was synthesized at different ratios of melamine to urea and its location during synthesis. Electrochemical studies have shown that the obtained carbon nitride is a promising material as metal-free catalyst for oxygen electrodes of fuel cells. It is shown that the best electrochemical characteristics of oxygen electrodes are obtained with an excess of nitrogen atoms in the sample. [ABSTRACT FROM AUTHOR]

Hydrogen fuel cell technology is gaining significant attention as a promising alternative for decarbonizing automotive vehicles. At the heart of hydrogen fuel cell technology is the electrode, composed of catalysts, supports, binders, and pores, which facilitates the half‐cell reactions and often governs the efficiency of fuel cells. Over the last decade, scientists have made great strides in discovering catalyst, support, and binder materials featuring unique nanostructures and compositions that significantly enhance the efficiency of those devices. While innovations must continue, we must not overlook how these materials are put together to form an electrode and how it impacts the overall efficiency. This perspective article discusses the urgent need for developing alternative electrodes for designing next generation hydrogen fuel cells. [ABSTRACT FROM AUTHOR]

Magnéli phases TinO2n − 1 are a series of sub-stoichiometric titanium oxides with a unique crystal structure, and Ti4O7 possesses the highest electronic conductivity while being able to maintain excellent chemical inertness in various corrosive environments, which is a required property for electrode materials in electrochemical systems. Therefore, Ti4O7 has become one of the major substitutes for carbon materials such as graphite and shows superior catalytic activity for electrode reactions and electrochemical stability in diverse batteries and electrochemical degradation systems, following the trend of carbon-free electrodes and costing less than the advanced electrodes such as boron-doped diamond. It has been demonstrated that Ti4O7 has great potential in the electrochemistry fields, especially as an electrode carrier. In this paper, we review the research progress of Ti4O7 as an electrode material in fuel cells, lithium-oxygen batteries, lithium-sulfur batteries, lithium-ion batteries, wastewater treatment, etc., including advanced fabrication technology, theoretical research, and application performance. Meanwhile, the current problems and future research directions of Ti4O7 are also pointed out. [ABSTRACT FROM AUTHOR]

Processing D-52425 Jülich, Germany In solid oxide cells (SOCs) exhibiting mixed ionic-electronic conductor air electrode (MIEC AE) (e.g. La0.6Sr0.4Co0.2Fe0.8O3--δ LSC(F)), the formation of insulating zirconate interphases at the air electrode/zirconia electrolyte--interface is commonly prevented by an interlayer of doped cerium oxide. This complex interaction has a tremendous influence on cell performance, as the morphology of the interlayer determines the amount and continuity of the zirconate interphases. The performance of fuel electrode supported cells (FESCs) exhibiting gadolinium-doped ceria (GDC) interlayers fabricated from different commercially available powders are compared. All of these layers were fabricated according to the same procedure. The cell performance is analyzed by means of current-voltage (CV) characteristics, electrochemical impedance spectroscopy (EIS) and subsequent impedance analysis by the distribution of relaxation times (DRT). Next to the cell testing at application-oriented conditions, impedance spectra are measured over a wide temperature ranging down to 250 °C to resolve polarization phenomena related to bulk, grain boundary and interfacial effects within and in-between the gadolinium-doped ceria (GDC) and the 8 mol% yttria-stabilized zirconia (8YSZ) electrolyte. Furthermore, symmetrical air electrode (SymAE) cells are analyzed to eliminate impedance contributions from the anode layer (AL) and the substrate. The electrochemical results are correlated to the microstructural features of the GDC/YSZ interface obtained from post-test focused ion beam (FIB)/scanning electron microscope (SEM) analysis. This comparison revealed significant differences in the cell performance, which could be attributed to the amount and continuity of the residual strontium zirconate (SZO) interphase. © 2023 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited. [ABSTRACT FROM AUTHOR]

Image processing is a powerful tool that allows for rapid and automated data parsing in settings that occupy large variable spaces and require large data sets. Feature detection on difficultly discerned backgrounds is a subset of image processing that facilitates the extraction of quantitative metrics from otherwise subjective data. Crack detection and quantification is an important capability in polymer electrolyte membrane fuel cell quality control, failure analysis, and optimization. This work presents a technique to perform crack detection and quantification which overcomes challenges faced by commonly used image segmentation techniques. We demonstrate the use of a geometrically filtered noise‐level detection technique to select a binary threshold value from which we then quantify how cracked a sample is. We demonstrate the accuracy of our technique using programmatically generated test images of known crack amounts and their performance on real‐world fuel cell catalyst layer samples. [ABSTRACT FROM AUTHOR]

The unique bicontinuous porous structure and superior electrical conductivity of nanoporous gold (NPG) make it a highly promising material for energy storage and conversion. Although the number of articles on the study of NPG-based materials in energy fields has increased significantly in recent years, the collation and review of these articles are still lacking. Herein, we address this gap by reviewing recent research activities on dealloyed NPG for energy storage and conversion applications. Firstly, the typical dealloying process for forming NPG is introduced. Subsequently, NPG-based composite catalysts used to catalyze water splitting and fuel cells electrode reactions are presented. Afterward, the applications of NPG for different types of electrodes of supercapacitors (SCs) and batteries are discussed. Finally, the studies on NPG for catalyzing CO2 reduction reaction (CO2RR) are reviewed. In a word, the recent research progress of NPG-based materials is reviewed and the future research directions are outlined, laying the cornerstone for the preparation of more advanced energy storage and conversion devices in the future. [ABSTRACT FROM AUTHOR]

Polymer Electrolyte Membrane (PEM) fuel cells are a promising source of alternative energy. However, their production is limited by a lack of well-established methods for quality control of their constituent materials like the membrane-electrode assembly during roll-to-roll manufacturing. One potential solution is the implementation of deep learning methods to detect unwanted defects through their detection in scanned images. We explore the detection of defects like scratches, pinholes, and scuffs in a sample dataset of PEM optical images using two deep learning algorithms: Patch Distribution Modeling (PaDiM) for unsupervised anomaly detection and Faster-RCNN for supervised object detection. Both methods achieve scores on performance metrics (ROC-AUC and PRO-AUC for PaDiM and AP for Faster-RCNN) that are comparable to their scores on benchmark datasets. These methods also have the potential to detect a wider range of defects compared to IR thermography and previous optical inspection methods. Overall, deep learning shows promise at detecting relevant defects of interest and has the potential to achieve real-time defect detection. • Deep learning models were used to detect defects in fuel cell electrode images. • Anomaly detection and object detection algorithms were tested. • Deep learning can detect a wider range of defects than previous methods. • Inference times show feasibility of real-time defect detection. [ABSTRACT FROM AUTHOR]

Developing hydrogen production and utilization technologies is a promising way to achieve large-scale applications of renewable energy. For both water electrolysis and fuel cell electrode reactions, electrocatalysts are critical to their energy conversion efficiencies. Among the various strategies for improving the performance of electrocatalysts, dealloying has been developed as a commonly used effective post-processing method. It originated from anti-corrosion science and can form metal materials with porous or "skin" nanostructures by selectively dissolving the active components in alloys. There are generally two types of dealloying methods: electrochemical dealloying and chemical dealloying. Electrochemical dealloying is more controllable, while chemical dealloying is simpler and less expensive. In this review, the fundamentals, histories, and progress of dealloying methods for energy conversion electrocatalysis are systematically summarized. Furthermore, current problems and prospects are proposed. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells are recognized as a promising energy conversion technology. Crucial to the field is the opportunity to reduce the costs of prototyping methodology. Due to the difficulty of conducting direct measurements inside the electrodes and fuel cell's channels, numerical modeling remains the primary tool for improving the understanding and analyzing a fuel cell operation. Here, a computational fluid dynamic simulation of a banded solid oxide fuel cell's stack, applied to enhance the geometrical design, is shown. A mathematical model, which includes momentum, heat, mass, and charge transport phenomena, was developed and used for the numerical simulation. The model was validated against the experimental study and confirmed its accuracy. The gas flow rate influence on the performance was investigated in details. Various arrangements of fuel and air channels were simulated and analyzed, including extending the system into a short stack. The proposed design modifications led to an increase in the volumetric power density of the stack compared to the existing prototype design. The proposed mathematical and numerical models were shown to be useful for testing further design modifications to the stack, including performance analysis, by changing the operating parameters of the system or applying new materials. [ABSTRACT FROM AUTHOR]

Glucose oxidation reaction (GOR) is vital to both the glucose fuel cell and glucose-sensing performance. Designing anodic materials with good conductivity and abundant active sites is critical to increase the efficiency of GOR. Here, we present the in situ generation of NiO/carbon rods (NiO/CRs) firstly from Ni-polyaniline (Ni-PANI) rod precursors, and then deposited Pt on NiO/CRs with a microwave-assisted process. The catalysts were characterized by various techniques, such as x-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, and x-ray photoelectron spectroscopy. Electrochemical measurements demonstrated that Pt/NiO/CRs-2 can act as highly efficient electrocatalysts for GOR. When used as anodic electrodes in non-enzymatic fuel cells, the Pt/NiO/CRs-2 exhibited the highest power density (1617.6 μW cm−2) with an open circuit voltage of 0.758 V. Moreover, Pt/NiO/CRs-2 also displayed a superior sensing performance for glucose detection with a sensitivity of 348.54 µA mM−2 cm−2 in the range of 1–2000 µM and 136.56 µA mM−2 cm−2 (2000–10,000 µM). The lower detection limit is 0.33 µM (S/N = 3). The enhanced electrochemical performance of Pt/NiO/CRs-2 may be due to the synergistic effect of Pt and NiO on the carbon rods, with the deposition of Pt not only facilitating the charge transfer but also inducing more active sites on NiO/CRs for GOR. The results may provide a promising viewpoint to design efficient catalysts for GOR. [ABSTRACT FROM AUTHOR]

Cerium dioxide (CeO2), especially doped cerium, is widely used as an electrolyte, while stannic oxide (SnO2) is known as a gas sensor material, but it is exceptionally new in solid-state ionics. In this work, a new semiconductor composite that consists of CeO2 and SnO2 was synthesized using a co-precipitation method and investigated for applications in solid oxide fuel cells (SOFCs). The as-prepared CeO2-SnO2 composite (n-n type) is employed as an electrolyte sandwiched between two Ni0.8Co0.15Al0.05LiO2-δ (NCAL) electrodes to fabricate fuel cells with a high power density of 1167 mW cm−2, accompanied by high open-circuit voltage (OCV) of 1.11 V at 550°C XRD, SEM, and HR-TEM analyses are employed to investigate the microstructure of the composites, illustrating that the as-prepared composite has particles of the nanometer size, without any other impurity phases. The electrical properties of the device are studied by EIS measurements. The results indicate that the synthesized CeO2-SnO2 composite exhibits higher ionic conductivity than that of the CeO2-SnO2 composite prepared by a dry grinding method. Considerable proton conductivity was also found for the CeO2-SnO2 composite. Interestingly, although two n-type semiconductor materials are composited for the electrolyte membrane, there is no short-circuit issue. Hence, the n-n heterojunction is proposed to explain the electron blocking mechanism. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon materials demonstrate high performance as electrodes in fuel cells and higher oxygen reduction reactivity than traditional Pt-based electrodes. However, the formation process of nitrogen-doped carbon materials has long been a mystery. In this study, the formation mechanism of nitrogen-doped carbon materials from polyaniline (PANI) pyrolysis was studied by the combination of in situ pyrolysis vacuum ultraviolet photoionization time-of-flight mass spectrometry (Py-VUVPI-TOF MS) and substrate-enhanced, laser-induced acoustic desorption source time-of-flight mass spectrometry (SE-LIAD-TOF MS). The initial pyrolysis species, including free radicals and intermediates, were investigated via in situ Py-VUVPI-TOF MS during the temperature-programmed desorption process (within tens of microseconds). The pyrolysis residues were collected and further investigated via SE-LIAD-TOF MS, revealing the product information of the initial pyrolysis products. The results show that the edge doping of carbon materials depends on free radical reactions rather than the direct substitution of carbon atoms by nitrogen atoms. Meanwhile, pyrrole nitrogen and pyridine nitrogen are formed by the free radical cyclization reaction and the amino aromatization reaction at the initial stage of pyrolysis, while the formation of graphitic nitrogen depends on the further polymerization reaction of pyrrole nitrogen and pyridine nitrogen. [ABSTRACT FROM AUTHOR]

The phosphoric acid (PA) distribution in the electrodes is a crucial factor for the performance of high‐temperature polymer electrolyte fuel cells (HT‐PEM FCs). Therefore, understanding and optimizing the electrolyte distribution is vital to maximizing power output and achieving low degradation. Although challenging, tracking the PA in nanometer‐sized pores is essential because most active sites in the commonly used carbon black‐supported catalysts are located in pores below 1 µm. For this study, a cell is operated at 200 mA cm−2 for 5 days. After this break‐in period, the cathode is separated from the membrane electrode assembly and subsequently investigated by cryogenic focused ion beam scanning electron microscopy (cryo FIB‐SEM) coupled with energy‐dispersive X‐ray spectroscopy (EDX) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). PA is located on the surface and in the bulk of the cathode catalyst layer. In addition, the PA distribution can be successfully linked to the gas diffusion electrode morphology and the binder distribution. The PA preferably invades nanometer‐sized pores and is uniformly distributed in the catalyst layer. [ABSTRACT FROM AUTHOR]

Simultaneous pollutant removal and electricity production using microbial fuel cells is a promising environmental sustainable technology that contributes to the circular economy. Numerous studies have been conducted previously using exogenously adding easily degradable sugars for electricity generation in microbial fuel cells (MFCs). However, in real-world applications involving wastewater, the performance of the process varies according on the source, the microorganisms presented and the electrodes employed. The simultaneous treatment of baker's yeast industrial effluents and electricity generation is investigated in various MFCs using titanium and graphite electrodes. Reduced chemical oxygen demand (COD) is reported to be between 73% and 92% depending on the MFC configuration and electrodes employed. The two-chamber MFC with titanium electrodes and inoculum sludge from upflow anaerobic sludge blanket reactors (UASB) perform better, reaching 51.02 mW/m2 and 12.74 μA/cm2 power and current densities, respectively. [Display omitted] • MFC technology removed up to 92% of COD from baker's yeast wastewater. • Dual chamber MFCs were more successful at treating high strength real wastewater. • The power generations were consistent with COD reductions in all MFCs. • UASB and activated sludge reactors in yeast industries could be used to develop MFC. [ABSTRACT FROM AUTHOR]

The property of cathode in the microbial fuel cell (MFC) was one of the key factors limiting its output performance. MnO2 nanorods were prepared by a simple hydrothermal method as cathode catalysts for MFCs. There were a number of typical characteristic crystal planes of MnO2 nanorods like (110), (310), (121), and (501). Additionally, there were great many hydroxyl groups on the surface of nanorod-like MnO2, which provided a rich set of active adsorption sites. The maximum power density (Pmax) of MnO2-MFC was 180 mW/m2, which was 1.51 times that of hydrothermally synthesized MnO2 (119.07 mW/m2), 4.28 times that of naturally synthesized MnO2 (42.05 mW/m2), and 5.61 times that of the bare cathode (32.11 mW/m2). The maximum voltage was 234 mV and the maximum stabilization time was 4 days. The characteristics of MnO2, including rod-like structure, high specific surface area, and high conductivity, were conducive to providing more active sites for oxygen reduction reaction (ORR). Therefore, the air cathode modified by MnO2 nanorods was a kind of fuel cell electrode with great application potential. [ABSTRACT FROM AUTHOR]

Simple Summary: In order to counter the increased deposition of greenhouse gases in the atmosphere, which has resulted in significant climatic changes, the production of alternative fuels to replace conventional fossil fuels has become necessary due to the rapidly diminishing concentration of fossil fuels and the rising global demand for energy. This investigation focused on two different samples that could be used as anolytes to produce energy in single- and double-chamber microbial fuel cells with a graphite electrode. In microbial fuel cells' energy production, the microbes consume organic substrates, use them in their metabolic processes, and produce valuable products that can be used as fuel to produce energy. The highest voltage outputs from the investigated bacterial strains were generated by strains A1 and A2, at 402 mV and 350 mV, respectively. Strain A6 of the ten different bacterial strains produced the least electricity, with a measurement of 35.03 mV. Natural resources are in short supply, and the ecosystem is being damaged as a result of the overuse of fossil fuels. The creation of novel technology is greatly desired for investigating renewable and sustainable energy sources. Microorganisms have received a lot of interest recently for their potential to transform organic waste into sustainable energy and high-value goods. New exoelectrogens that can transmit electrons to electrodes and remove specific wastewater contaminants are expected to be studied. In this study, we examined three distinct samples (as determined by chemical oxygen demand and pH) that can be used as anolytes to generate power in single-chamber and double-chamber microbial fuel cells using graphite electrodes. Wastewater from poultry farms was studied as an exoelectrogenic anolyte for microbial fuel cell power generation. The study examined 10 different bacterial strains, numbered A1 through A10. Due to their highly anticipated capacity to metabolize organic/inorganic chemicals, the diverse range of microorganisms found in poultry wastewater inspired us to investigate the viability of generating electricity using microbial fuel cells. From the investigated bacterial strains, the highest voltage outputs were produced by strains A1 (Lysinibacillus sphaericus) and A2 (Bacillus cereus), respectively, at 402 mV and 350 mV. Among the 10 different bacterial strains, strain A6 generated the least amount of electricity, measuring 35.03 mV. Furthermore, a maximum power density of 16.16 1.02 mW/m2 was achieved by the microbial fuel cell using strain A1, significantly outperforming the microbial fuel cell using a sterile medium. The strain A2 showed significant current and power densities of 35 1.12 mA/m2 and 12.25 1.05 mW/m2, respectively. Moreover, in the two representative strains, chemical oxygen demand removal and Coulombic efficiency were noted. Samples from the effluent anode chamber were taken in order to gauge the effectiveness of chemical oxygen demand removal. Wastewater had an initial chemical oxygen demand content of 350 mg/L on average. Strains A1 and A2 decomposed 94.28% and 91.71%, respectively, of the organic substrate, according to the chemical oxygen demand removal efficiency values after 72 h. Strains A1 and A2 had electron donor oxidation efficiencies for 72 h of 54.1% and 60.67%, respectively. The Coulombic efficiency increased as the chemical oxygen demand decreased, indicating greater microbial electroactivity. With representative strains A1 and A2, Coulombic efficiencies of 10% and 3.5%, respectively, were obtained in the microbial fuel cell. The findings of this study greatly advance the field as a viable source of power technology for alternative energy in the future, which is important given the depletion of natural resources. [ABSTRACT FROM AUTHOR]

[Display omitted] Owing to considerable energy constraints and global warming phenomenon, to find alternative sources of renewable and affordable energy has become a highly prerequisite in this current era. Use of sustainable technologies in this regard for renewable fuel retention applications has become more beneficial in encouraging the broad usage of clean energy. Conjugated microporous polymers (CMPs) are a distinct family of composites, that merge extensive the π-conjugation with microporous structure. The CMPs have been recognized as an essential subclass of porous composites, ever since their development in 2007. The CMPs have been developed with a number of distinct configurations and characteristics, which allows for the versatility of conjugated framework cellular implementations and mesoporous structure. The exploration of CMPs in sustainable fuel devices is crucial for the development of CMP-based composites and their use in sustainability and environmental design. Numerous network developing processes and synthesized building components provide a huge heterogeneity of CMPs with various characteristics and design patterns. As a consequence, CMPs have been employed here for cathode/anode materials for lithium ion batteries (LIBs), sodium/potassium LIBs, supercapacitors, fuel cell electrode for solar cell, hydrogen storage materials, photocatalytic hydrogen and oxygen production reaction (HER, OER), photocatalytic CO 2 reduction and so on. Due to the large surface areas of these composites, the distinctive charge storage mechanisms found in CMPs are explored, and a synopsis of how CMPs might facilitate ultrafast in desirable variety is presented. In addition, an evaluation between CMPs and linear polymers is presented, which provides further assistance for the synthesis of active materials. The most significant shortcomings experienced by CMPs in the domains of energy production have been evaluated, and potential strategies, synthetic process with reactions, physiochemical properties along with morphology have been demonstrated. Thus, this review is intended to be an entertaining and motivating study in the scientific community of the energy storage experts. [ABSTRACT FROM AUTHOR]