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Nafion, as a key component in the catalyst layer, plays a crucial role in the mass transport and electrochemical reactions within the catalyst layer. In this study, a numerical method is employed to reconstruct the three-dimensional nanoscale microstructure of the catalyst layer, including pores, Nafion, carbon particles, and Pt phases. A pore-scale model in which the Knudsen effect is taken into account is used to simulate the impact of Nafion contents on the interparticle transport and electrochemical reactions within the catalyst layer. The results show that the pore-scale simulation based on the reconstructed model can clearly reveal the mass transport process and highly uneven distribution of each physical quantity in the nanoscale particles and pores; When the Nafion content is relatively higher, the proton current distribution at the Pt/Nafion interface is relatively more uniform and the proton supply is sufficient. However, there is an inverse correlation between the oxygen mole concentration on the Pt surface and the Nafion content, which is the dominant factor affecting the electrochemical reactions on the Pt particle surface. When the Nafion content is lower, the proton supply becomes the dominant factor in the electrochemical reaction on the surface of Pt particles due to the weak connectivity of Nafion between the agglomerates. The combined effect of oxygen and proton transport result in the optimal Nafion volume fractions of 0.296 and 0.262 at voltages of 0.8 V and 0.7 V, respectively. The optimal Nafion volume fraction ranges between 0.224 and 0.262 at 0.6 V. As the voltage decreases, the effect of oxygen transport becomes more significant, and the optimal Nafion content decreases accordingly. [Display omitted] • A microstructure CL model consisted of nanoscale particles is reconstructed by stochastic numerical technology. • Nafion's effects on the transport among nanoscale particles are numerically observed directly. • The mass transport and multi-physics distribution characteristics among nanoscale Pt, C and Nafion particles are revealed. • The corresponding relationship between the working voltage and optimal Nafion content is obtained. [ABSTRACT FROM AUTHOR]

The results of diagnostic tests under steady-state speed conditions of an unloaded engine do not fully reflect the emissivity of vehicles adapted to run on natural gas. Therefore, it is reasonable to pay attention to the emissions performance of these vehicles under dynamic conditions. In this regard, the tests were carried out on a chassis dynamometer with the engine fueled by gasoline and natural gas. Due to the area of operation of natural gas vehicles being usually limited to urban areas, the urban phases of the NEDC (New European Driving Cycle) and WLTC (Worldwide harmonized Light-duty vehicles Test Cycle) were adapted. While CO2 emissions are lower when fueled by natural gas, CH4 emissions can be high, which is related to momentary changes in the composition of the combustible mixture. Although CH4 emissions are higher when the engine runs on natural gas, the CO2eq value is, depending on the driving cycle, about 15–25% lower than when running on petrol. Additionally, studies have shown that in engines adapted to run on CNG (compressed natural gas), it is advisable to consider the use of catalytic converters optimized to run on natural gas, as is the case with vehicles which are factory–adapted to run on CNG. [ABSTRACT FROM AUTHOR]

Solid‐state lithium metal batteries (LMBs), constructed through the in situ fabrication of polymer electrolytes, are considered a critical strategy for the next‐generation battery systems with high energy density and enhanced safety. However, the constrained oxidation stability of polymers, such as the extensively utilized polyethers, limits their applications in high‐voltage batteries and further energy density improvements. Herein, an in situ fabricated fluorinated and crosslinked polyether‐based gel polymer electrolyte, FGPE, is presented, exhibiting a high oxidation potential (5.1 V). The fluorinated polyether significantly improves compatibility with both lithium metal and high‐voltage cathode, attributed to the electron‐withdrawing −CF3 group and the generated LiF‐rich electrolyte/electrode interphase. Consequently, the solid‐state Li||LiNi0.6Co0.2Mn0.2O2 batteries employing FGPE demonstrate exceptional cycling performances of 1000 cycles with 78 % retention, representing one of the best results ever reported for polymer electrolytes. Moreover, FGPE enables batteries to operate at 4.7 V, realizing the highest operating voltage of polyether‐based batteries to date. Notably, our designed in situ FGPE provides the solid‐state batteries with exceptional cycling stability even at practical conditions, including high cathode loading (21 mg cm−2) and industry‐level 18650‐type cylindrical cells (1.3 Ah, 500 cycles). This work provides critical insights into the development of oxidation‐stable polymer electrolytes and the advancement of practical high‐voltage LMBs. [ABSTRACT FROM AUTHOR]

Solid‐state lithium metal batteries (LMBs), constructed through the in situ fabrication of polymer electrolytes, are considered a critical strategy for the next‐generation battery systems with high energy density and enhanced safety. However, the constrained oxidation stability of polymers, such as the extensively utilized polyethers, limits their applications in high‐voltage batteries and further energy density improvements. Herein, an in situ fabricated fluorinated and crosslinked polyether‐based gel polymer electrolyte, FGPE, is presented, exhibiting a high oxidation potential (5.1 V). The fluorinated polyether significantly improves compatibility with both lithium metal and high‐voltage cathode, attributed to the electron‐withdrawing −CF3 group and the generated LiF‐rich electrolyte/electrode interphase. Consequently, the solid‐state Li||LiNi0.6Co0.2Mn0.2O2 batteries employing FGPE demonstrate exceptional cycling performances of 1000 cycles with 78 % retention, representing one of the best results ever reported for polymer electrolytes. Moreover, FGPE enables batteries to operate at 4.7 V, realizing the highest operating voltage of polyether‐based batteries to date. Notably, our designed in situ FGPE provides the solid‐state batteries with exceptional cycling stability even at practical conditions, including high cathode loading (21 mg cm−2) and industry‐level 18650‐type cylindrical cells (1.3 Ah, 500 cycles). This work provides critical insights into the development of oxidation‐stable polymer electrolytes and the advancement of practical high‐voltage LMBs. [ABSTRACT FROM AUTHOR]

Introducing continuous mesochannels into covalent organic frameworks (COFs) to increase the accessibility of their inner active sites has remained a major challenge. Here, we report the synthesis of COFs with an ordered bicontinuous mesostructure, via a block copolymer self‐assembly‐guided nanocasting strategy. Three different mesostructured COFs are synthesized, including two covalent triazine frameworks and one vinylene‐linked COF. The new materials are endowed with a hierarchical meso/microporous architecture, in which the mesochannels exhibit an ordered shifted double diamond (SDD) topology. The hierarchically porous structure can enable efficient hole‐electron separation and smooth mass transport to the deep internal of the COFs and consequently high accessibility of their active catalytic sites. Benefiting from this hierarchical structure, these COFs exhibit excellent performance in visible‐light‐driven catalytic NO removal with a high conversion percentage of up to 51.4 %, placing them one of the top reported NO‐elimination photocatalysts. This study represents the first case of introducing a bicontinuous structure into COFs, which opens a new avenue for the synthesis of hierarchically porous COFs and for increasing the utilization degree of their internal active sites. [ABSTRACT FROM AUTHOR]

Introducing continuous mesochannels into covalent organic frameworks (COFs) to increase the accessibility of their inner active sites has remained a major challenge. Here, we report the synthesis of COFs with an ordered bicontinuous mesostructure, via a block copolymer self‐assembly‐guided nanocasting strategy. Three different mesostructured COFs are synthesized, including two covalent triazine frameworks and one vinylene‐linked COF. The new materials are endowed with a hierarchical meso/microporous architecture, in which the mesochannels exhibit an ordered shifted double diamond (SDD) topology. The hierarchically porous structure can enable efficient hole‐electron separation and smooth mass transport to the deep internal of the COFs and consequently high accessibility of their active catalytic sites. Benefiting from this hierarchical structure, these COFs exhibit excellent performance in visible‐light‐driven catalytic NO removal with a high conversion percentage of up to 51.4 %, placing them one of the top reported NO‐elimination photocatalysts. This study represents the first case of introducing a bicontinuous structure into COFs, which opens a new avenue for the synthesis of hierarchically porous COFs and for increasing the utilization degree of their internal active sites. [ABSTRACT FROM AUTHOR]

This study focuses on the detailed analysis of exhaust emissions from multi-point fuel injection (MPFI) engines by manipulating the injection parameters through a programmable electronic control unit. In addition, tests are carried out using different generations of catalytic converters and checking that their working temperature is correct using a thermographic camera, verifying operation, to evaluate their effect on emission reduction. Detailed comparisons of the results between these configurations will allow the identification of the combination that reduces emissions the most without compromising engine efficiency and performance. This research aims to promote a more sustainable approach in the automotive sector by properly configuring systems, but also by demonstrating the technical robustness of their application in vehicles. It has also helped to verify that varying injection and ignition parameters help to fine-tune fuel injection, resulting in efficient combustion. Combining this variation with catalytic converters has further reduced exhaust pollutants. [ABSTRACT FROM AUTHOR]

A novel and selective method has been developed for high-accuracy determination of Pd, Pt and Rh in complex autocatalyst matrices using isotope dilution (ID) analysis (for Pt and Pd) and internal standard (IS) matching (for Rh) with ICP-time-of-flight mass spectrometry (ICP-TOFMS). By using a desolvating inlet interface and He collision gas, spectral interferences on selected isotopes (e.g., 105Pd, 195Pt, 196Pt) were successfully removed. Calibration is performed by exact-matching ID analysis for Pd (104Pd/105Pd) and Pt (196Pt/195Pt) and IS matching with 101Ru for monoisotopic 103Rh. Due to the quasi-simultaneous determination of all the isotopes of interest by ICP-TOFMS, isotope ratio precision was improved in comparison with that of sequential instrumentation, thus leading to reduced measurement uncertainties of <1% (k = 2), as required by autocatalyst manufacturers. This represents an approximately 2–3-fold improvement for Rh and Pd and 6-fold improvement for Pt in comparison to the uncertainties achieved using the same measurement strategy for sequential ICP-MS instrumentation. The method has been applied to the characterisation of a candidate CRM LGC3101 (unused automobile catalyst) containing high levels of Zr and Hf and validated by the analysis of similar matrix CRMs and by participation in an interlaboratory exercise. [ABSTRACT FROM AUTHOR]

Rhenium is utilized as an additive to improve the high-temperature strength and stability of materials, such as nickel-based superalloys, which are employed in jet engine turbine blades, alloys for ultrahigh-temperature thermocouples, and platinum catalysts, which are used in oil refining. Currently, around 80% of rhenium demand is for superalloy production, and this demand has been increasing with the increase in demand for aircrafts. The abundance of rhenium in the earth's crust is only 1 ppb (10−9), which is less than those of platinum and gold. Owing to the rare and unevenly distributed nature of rhenium, there is the risk of supply disruption and rapid increases in its price. In this article, the recent situation of rhenium and its compounds are reviewed, especially with respect to their demand, distribution characteristics, smelting, and recycling. Some of the technologies recently developed for smelting and recycling rhenium are also introduced. [ABSTRACT FROM AUTHOR]

[Display omitted] • Automotive brake pad debris (BPD) can serve as effective Fenton catalysts. • BPD achieves 90% degradation of organic pollutants in 10 mins. • Oxidative treatment induces in-situ growth of Fe in BPD into Fe 2 O 3 nanocrystals. • Electronic interaction between Fe and Cu on BPD facilitates Fe(II)/Fe(III) cycling. • Triple Fe-C-Cu site of Cu/C-Fe 2 O 3 collaboratively activated H 2 O 2 to produce ·OH. The arbitrary disposal of used brake pads from motor vehicles has resulted in severe heavy metal pollution and resource wastage, highlighting the urgent need to explore the significant untapped potential of these discarded materials. In this study, The in-situ growth of highly dispersed Fe 2 O 3 nanocrystals was achieved by simple oxidation annealing of brake pad debris(BPD). Interestingly, Cu remained unoxidized and acted as a "valence state transformation bridge of Fe 2 O 3 " to construct the "triple Fe-C-Cu sites". The Fenton degradation experiment of pollutants was conducted under constant temperature conditions at 40 °C, a stirring rate of 1300 rpm, a pH value of 3, a catalyst dosage of 0.5 g/L, pollutant dosage ranging from 50 to 400 mg/L, and H 2 O 2 dosage of 0.25 g/L. Experimental results showed that BPD treated at 300 °C for 2 h exhibited optimal Fenton-like oxidation activity, achieving rapid degradation of over 90 % of refractory antibiotics, such as tetracycline and ciprofloxacin, in organic wastewater within 10 min. This remarkable performance was mainly attributed to the synergistic effect of "Fe-C-Cu triple sites", where the electron-donating role of C in the Fe-C and Cu-C interfaces facilitated the conversion of the Fe(III) to Fe(II) and Cu(II) to Cu(I). In addition, the ability of Cu2+ to accept electrons at the Fe-Cu interface promoted the transition from Fe (II) to Fe (III). This "balance of electron gain and loss" accelerated the interfacial electron transfer and the recycle of dual Fenton sites, Fe(II)/Fe(III) and Cu(I)/Cu(II), to generate more ·OH from H 2 O 2. Therefore, this strategy of functionalizing BPD as Fenton-like catalysts without the addition of external Fe provides intriguing prospects for understanding the construction of Fe-based Fenton catalysts and resource utilization of Fe-containing solid waste materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow structure favors active site exposure and mass transport of S-NiCo 2 O 4 -6. • S2− doping reduces the oxidation potential of Ni cations during the OER process. • The reduced oxidation potential promotes the formation of γ-NiOOH active sites. • S2− doping enhances the conductivity of NiCo 2 O 4. Inducing the surface reconstruction of spinels is critical for improving the electrocatalytic oxygen evolution reaction (OER) activity. Herein, S-doped NiCo 2 O 4 hollow cubic nanocage was synthesized by anion etching Metal-Organic Frameworks (MOFs) template and air annealing strategies. The hollow structure possesses a large specific surface area and pore size, facilitating active site exposure and mass transport. S2− doping regulates the electronic structure, reducing the oxidation potential of Ni sites during the OER process, thus promoting the surface reconstruction into γ-NiOOH active species. Meanwhile, S2− doping enhances conductivity, accelerating interfacial charge transfer. As a result, S-NiCo 2 O 4 -6 exhibits superior OER activity (262 mV overpotential @ 10 mA cm−2) and stability in 1.0 M KOH solution. Furthermore, 20 % Pt/C‖S-NiCo 2 O 4 -6 only needs 1.832 V to achieve 50 mA (the electrochemical active area is 4 cm2) in a homemade anion exchange membrane (AEM) electrolyzer. This work proposes a novel approach for preparing efficient anion-doped spinel-based OER electrocatalysts. [ABSTRACT FROM AUTHOR]

The efficiency of incorporating deuterium into 4-aminobutanoic acid (GABA) has been studied. The use of D2O at 200°C makes it possible to introduce into GABA an average of about 0.5 deuterium atoms, D2O with trifluoroacetic acid (1 : 1) at 250°C, an average 1.49 deuterium atoms with a yield of 15%. The solid-phase method permits introducing about 3 deuterium atoms per GABA molecule. During isotopic exchange with D2O, the use of a palladium–rhodium mixture pretreated with deuterium gas made it possible to produce [D]GABA with the deuterium content of 4.5–4.6 atoms. But in both cases, the yields of [D]GABA were low. Preparative amounts of [D]GABA were produced engaging additional supports. The best result was obtained when applying GABA to zeolite. Using D2O with 5% Pd/BaSO4–GABA–zeolite pretreated with deuterium gas, allows producing [D]GABA with an average content of 1.5–2.0 deuterium atoms and a yield of about 30%. [ABSTRACT FROM AUTHOR]

The storage and transfer of energy require a safe technology to mitigate the global environmental issues resulting from the massive application of fossil fuels. Fuel cells have used hydrogen as a clean and efficient energy source. Nevertheless, the storage and transport of hydrogen have presented longstanding problems. Recently, liquid organic hydrogen carriers (LOHCs) have emerged as a solution to these issues. The hydrogen storage technique in LOHCs is more attractive than those of conventional energy storage systems like liquefaction, compression at high pressure, and methods of adsorption and absorption. The release and acceptance of hydrogen should be reversible by LOHC molecules following favourable reaction kinetics. LOHCs comprise liquid and semi-liquid organic compounds that are hydrogenated to store hydrogen. These hydrogenated molecules are stored and transported and finally dehydrogenated to release the required hydrogen for supplying energy. Hydrogenation and dehydrogenation are conducted catalytically for multiple cycles. This review elaborates on the characteristics of different LOHC molecules, based on their efficacy as energy generators. Additionally, different catalysts used for both hydrogenation and dehydrogenation are discussed. [ABSTRACT FROM AUTHOR]

Efficient delafossite CuCoO 2 photo(electro)catalysts necessitate effective separation and transport of photogenerated carriers to enable the production of solar fuel. Addressing this requirement, the current study employed facet engineering to induce the surface polarization effect. Hydrothermal conditions were utilized to prepare CuCoO 2 photo(electro)catalysts with diverse morphologies and sizes. Specifically, CuCoO 2 hexagonal nanosheets, predominantly exposing the (001) facet and possessing a thickness of 120 nm, exhibited optimal performance, as evidenced by a photocurrent density of 40 μA/cm2 under zero-bias conditions and 90 % degradation of tetracycline hydrochloride within 150 min. To overcome the limitations associated with hydrothermal preparation, Ca substitutional doping was employed. This doping strategy caused disruption of the O–Cu–O dumbbell-like structural motif, transforming CuCoO 2 into an open-layered structure while simultaneously reducing the thickness of CuCoO 2 hexagonal nanosheets to 30 nm. Consequently, an enhancement in the photo(electro)catalytic performance was achieved. By striking a balance between the surface polarization effect and the doping effect, CuCoO 2 hexagonal nanosheets with 0.5 % Ca doping content and a thickness of 80 nm exhibited the most significant photo(electro)catalytic performance. This study presents a feasible strategy and concept for optimizing the morphology and hydrothermal preparation conditions of CuCoO 2 nanomaterials, leading to improved photo(electro)catalytic performance. [Display omitted] • Surface polarization enhances carrier separation and transport in CuCoO 2 photoelectrodes. • CuCoO 2 hexagonal nanosheets exhibit superior photo(electro)catalytic activity. • Ca doping overcomes limitations in hydrothermal synthesis for preparation thinner CuCoO 2 nanosheets. [ABSTRACT FROM AUTHOR]

Wireless power transfer (WPT) technology based on magnetic resonance (a basic physical phenomenon) can directly transfer energy from the source to the load without wires and other physical contacts, and has been successfully applied to implantable medical devices, electric vehicles, robotic arms and other fields. However, due to the frequency splitting of near-field coupling, the resonant WPT system has some unique limitations, such as poor transmission stability and low efficiency. Here, we propose anti-resonance with level pinning for high-performance WPT. By introducing the anti-resonance mode into the basic WPT platform, we uncover the competition between dissipative coupling and coherent coupling to achieve novel level pinning, and construct an effective anti-parity-time (anti- PT)-symmetric non-Hermitian system that is superior to previous PT -symmetric WPT schemes. On the one hand, the eigenvalue of the anti- PT -symmetric system at resonance frequency is always pure real in both strong and weak coupling regions, and can be used to overcome the transmission efficiency decrease caused by weak coupling, as brought about by, for example, a large size ratio of the transmitter to receiver, or a long transmission distance. On the other hand, due to the level pinning effect of the two kinds of coupling mechanisms, the working frequency of the system is guaranteed to be locked, so frequency tracking is not required when the position and size of the receiver change. Even if the system deviates from the matching condition, an efficient WPT can be realized, thereby demonstrating the robustness of the level pinning. The experimental results show that when the size ratio of the transmitter coil to the receiver coil is 4.29 (which is in the weak coupling region), the transfer efficiency of the anti- PT -symmetric system is nearly 4.3 (3.2) times higher than that of the PT -symmetric system when the matching conditions are satisfied (deviated). With the miniaturization and integration of devices in mind, a synthetic anti- PT -symmetric system is used to realize a robust WPT. Anti- PT -symmetric WPT technology based on the synthetic dimension not only provides a good research platform for the study of abundant non-Hermitian physics, but also provides a means of going beyond traditional near-field applications with resonance mechanisms, such as resonance imaging, wireless sensing and photonic routing. [ABSTRACT FROM AUTHOR]

Platinum group metals (PGMs), including palladium, play a pivotal role in various industries due to their unique properties. Palladium is frequently employed in technologies aimed at environmental preservation, such as catalytic converters that reduce harmful emissions from vehicles, and in the production of clean energy, notably in the hydrogen evolution process. Regrettably, the production of this vital metal for our environment is predominantly centered in two countries—Russia and South Africa. This centralization has led to palladium being classified as a critical raw material, emphasizing the importance of establishing a secure and sustainable supply chain, as well as employing the most efficient methods for processing materials containing palladium. This review explores techniques for palladium production from primary sources and innovative recycling methods, providing insights into current technologies and emerging approaches. Furthermore, it investigates the economic aspects of palladium production, including price fluctuations influenced by emission regulations and electric vehicle sales, and establishes connections between palladium prices, imports from major producers, as well as copper and nickel prices, considering their often co-occurrence in ores. [ABSTRACT FROM AUTHOR]

Since 2011, the volume of passenger air transport grew nearly 7.5%/year, while freight air transport grew 3.6%/year regarding to the performed kilometers. The expansion of the aviation sector resulted increasing fuel consumption, too. The growing usage of fossil-based jet fuel results significant particle and carbon dioxide emissions, which causes remarkable environment pollution. This emission can only be reduced with using alternative jet fuels, especially those are originated from natural/waste fatty acid/-ester triglyceride sources. The aim of the experimental work was to compare industrially applied sulfide-state catalysts containing different transition metals from the aspect of catalytic conversion of mixtures of waste coconut oil and unrefined kerosene to produce jet fuel at various process parameters (temperature = 280–360 °C, liquid hourly space velocity = 1.0–3.0 h−1, pressure = 30 bar, hydrogen/hydrocarbon volume ratio = 600 Nm3/m3) in a continuous down-flow tubular reactor system. The obtained products contributes to decrease in particle and carbon dioxide emission of aircrafts due to their lower aromatic content. The smoke point of the products obtained at favorable process parameters was higher than 30 mm, while the requirement in ASTM D 1655 standard is minimum 25 mm. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have driven great interest due to a large specific surface area to volume ratio and adjustable surface behaviors, which show huge potentials for enhancing the activity of energy conversion and property optimization. In order to regulate the physicochemical properties of photocatalyst for water splitting reaction, defect engineering on 2D materials have drawn great attention. Meanwhile, a widely used strategy to improve the H 2 evolution rate kinetics has been achieved. In this paper, we prepared AgBr/g-C 3 N 4 catalyst by chemical precipitation. The obtained photocatalyst shows a unique charge transfer pathway. In addition, a deep understanding of the proton shuttle during H 2 evolution reactions can offer profound opinion into heterostructure construction and property optimization. It is found that the enhanced performance is correlated to the superiority of the S-scheme heterojunction and defect engineering on graphitic carbon nitride 2D materials. This work offers a novel method for improving efficiency in terms of energy conversion and property optimization. [Display omitted] • Surface nitrogen vacancy is instrumental in the chemisorption and activation of H 2 O. • S-scheme band of AgBr/g-C 3 N 4 is conjectured by the experiments and DFT calculations. • The prolonged photocarrier lifetime has increased H 2 production. • The results of XPS are consistent with the mechanism of S-scheme heterojunction. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes an advanced power converter setup to charge an electric vehicle battery from a renewable energy source, such as solar photovoltaic. An improved Z‐source DC–DC boost converter (IZSBC) is utilized in the first stage. A synchronous rectifier (SR) of a phase‐shifted full‐bridge converter (PSFBC) with continuous conduction mode (CCM) is employed in the second stage using the zero voltage switching (ZVS) technique to provide isolation between the source and the load. To address the disadvantage of undesirable dynamic characteristics of the PSFBC‐SR, an advanced voltage control using the advanced model predictive controller (AMPC) is suggested to improve the dynamic characteristic of the PSFBC‐SR converter and prevent output voltage overshoot. An AMPC‐based new control method is preferred to eliminate body‐diode conduction for improved efficiency at any load conditions. Simulation and experimental designs of 0.5 kW with a 25 V DC input from the SPV, a boosted output of 100 V for a 60 V, 16 Ah battery bank and switching frequencies of 100 and 250 kHz for IZSBC and PSFBC‐SR, respectively, are produced and evaluated. Results show an efficiency of 93.7% with 31.44 W loss in simulations and 93.94% with 30.25 W loss in hardware tests. The preferred system has fast dynamics and is robust to sudden load impedance changes, thereby improving current tracking and reducing converter losses. The AMPC strategy proposed in this paper can increase conversion efficiency and control the output voltage without additional gain tuning. [ABSTRACT FROM AUTHOR]

Constantly tightening vehicle emission standards leads to the creation of new technologies for reducing the content of toxic substances in exhaust gases while maintaining the highest possible engine performance. At the moment, however, it is clear that with regard to future emission standards, despite the technologically highly refined system of catalytic converters, the reduction of emissions with the help of catalytic converters alone will be insufficient. That is why a variable exhaust manifold/system was developed and patented, which has a significant impact on the reduction of vehicle emissions. This innovation enables three working modes of the engine, depending on the demand and output power requirements. The presented article presents the complex architecture of the proposed system, including the description and simulation of individual operating modes. The first working mode is the most ecological and economical mode, but it has a relatively lower performance. The second working mode is characterized by the production of higher power, and the third mode can be used at high engine loads. [ABSTRACT FROM AUTHOR]

A porous and hollow nanobox catalyst consisting of a nitrogen-doped carbon framework embedded with FeCo alloy and MnO components was successfully prepared, taking into consideration the effects of the intrinsic electric field and hollow/porous support carriers for electrocatalyst design. [Display omitted] • A porous carbon nanobox embedded with FeCo alloy and MnO nanoparticle was prepared. • A built-in electric field expedites charge transfer and enhances ORR-OER activity. • The porous carbon nanobox contributes to rapid mass/charge transport. The advancement of bifunctional oxygen catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is imperative yet challenging for the optimization of Zn-air batteries. In this study, we reported the successful incorporation of a novel Mott-Schottky catalytic site within a MnO-FeCo heterojunction into an N -doping carbon nanobox, taking into consideration the effects of the intrinsic electric field and hollow/porous support carriers for electrocatalyst design. As expected, the resulting heterogeneous catalyst exhibited an encouraging half-wave potential of 0.88 V and an impressive limiting-current density of 5.62 mA/cm2 for the ORR, as well as a minimal overpotential of 271 mV at 10 mA/cm2 for the OER, both in alkaline conditions. Furthermore, the Zn-air battery constructed with the heterojunction nanobox product displayed a decent potential gap of 0.621 V, an outstanding power density of 253 mW/cm2, a considerable specific capacity of 761 mAh/g Zn , and exceptional stability, with up to 336 h of cycling charging and discharging operation. Consequently, this method of modulating the catalyst's surface charge distribution through an internal electric field at the interface and facilitating mass transport offers a novel avenue for the development of robust bifunctional oxygen catalysts. [ABSTRACT FROM AUTHOR]

The CO 2 electrochemical reduction reaction (CO 2 ERR) offers an effective way to solve the problems of energy storage fluctuation and CO 2 over-emission at the same time. However, the mass transfer limitation during CO 2 ERR owing to the gaseous property of CO 2 greatly restricts the efficiency and selectivity of CO 2 reduction. Here, we report, for the first time, the design of a copper-zinc (CuZn) bimetal decorated superstructure catalyst (CuZn@KCA) via capitalizing on porous N-doped konjac glucomannan (KGM) aerogel and CuZn metal organic frameworks (CuZn-MOF), based on multiphysics infinite elemental simulations. The CuZn@KCA catalysts show high performance for CO 2 ERR (faradaic efficiency for HCOOH reaches 75% at −1.0 V vs. RHE). As demonstrated by infinite elemental simulations and detailed characterizations, the improved CO 2 ERR is attributed to the mass transfer enhancement effect of the superstructure catalyst on the reaction process (The mass transfer with CuZn@KCA is 16 times higher than that with CuZn-MOF). As such, the strategy for crafting a hierarchical superstructure might open up an avenue to improve the reaction activity of CO 2 ERR. • CuZn@KCA superstructure catalyst is designed and fabricated through finite element simulations and ice-templated method. • CuZn@KCA exhibits prominent CO 2 ERR performance and excellent stability for long time operation. • Fast charge and mass transfer rates attributed to hierarchical superstructure lead to higher CO 2 conversion FE. [ABSTRACT FROM AUTHOR]

In this paper, a new Buck-Boost converter with coupled inductor that can eliminate right-half-plane (RHP) zeros is proposed. The steady-state model and small-signal model of the proposed Buck-Boost converter in continuous conduction mode (CCM) are established and analysed, and its control-to-output voltage transfer function is obtained. The condition for this proposed converter to eliminate RHP zeros is derived based on the Mason formula. The comparisons among the other extant four Buck-Boost converters and the proposed Buck-Boost converter are carried out, and it shows that the proposed Buck-Boost converter has the advantage of eliminating RHP zeros. Finally, some simulations and circuit experiments are presented for confirmation. [ABSTRACT FROM AUTHOR]

In this article we shed light on newly emerging perspectives to characterize and understand the interplay of diffusive mass transport and surface catalytic processes in pores of gas phase metal catalysts. As a case study, nanoporous gold, as an interesting example exhibiting a well-defined pore structure and a high activity for total and partial oxidation reactions is considered. PFG NMR (pulsed field gradient nuclear magnetic resonance) measurements allowed here for a quantitative evaluation of gas diffusivities within the material. STEM (scanning transmission electron microscopy) tomography furthermore provided additional insight into the structural details of the pore system, helping to judge which of its features are most decisive for slowing down mass transport. Based on the quantitative knowledge about the diffusion coefficients inside a porous catalyst, it becomes possible to disentangle mass transport contributions form the measured reaction kinetics and to determine the kinetic rate constant of the underlying catalytic surface reaction. In addition, predictions can be made for an improved effectiveness of the catalyst, i.e., optimized conversion rates. This approach will be discussed at the example of low-temperature CO oxidation, efficiently catalysed by npAu at 30 °C. The case study shall reveal that novel porous materials exhibiting well-defined micro- and mesoscopic features and sufficient catalytic activity, in combination with modern techniques to evaluate diffusive transport, offer interesting new opportunities for an integral understanding of catalytic processes. [ABSTRACT FROM AUTHOR]

Given the recent trends in the MPPT converters in PV systems, which have been researched extensively to improve design, modified closed-loop converter technology based on SoC is presented here. This paper aims to provide detailed information on the modern-day solar Maximum Power Point Tracking (MPPT) controller and Battery Management System (BMS). Most MPPT controller examination researched in the past is suitable only for fixed-rated battery capacity, which limits the converter capability and applications. The proposed paper uses the distributed energy management control technique to dispatch multi-battery charging based on the State of Charge (SoC). The converter construction is modified here as per the prerequisite of the model. The system hardware is developed and tested using Atmega2560 low power RISC based high-performance microcontroller. The batteries' SoC level and State of Health (SoH) are calculated using embedded sensors and communication platforms through the IoT platform and Global System Monitoring (GSM) technology. The GSM and IoT technology ensure that the different batteries are monitored periodically, and any irregularities are immediately addressed through the distributed energy management control technique. This ensures a safe, reliable, and effective charging of multiple batteries with increased accuracy, thereby maximizing battery life and reducing operational costs. [ABSTRACT FROM AUTHOR]

The effects of Electromagnetic Interference (EMI) in Inductive Power Transfer (IPT) for electric vehicle charging circuits are elaborated with Common Mode (CM) emission. Electromagnetic Compatibility (EMC) has to be sustained in the circuits such that it is prone to the effects of interferences, noises and disturbances. These issues can be addressed at the initial product development stage, with accurate identification of the parameters that influence the CM emission in the circuit. The analysis of EMI focuses on three features, namely Source of EMI, Coupling path and Receptor. In the IPT model, the primary source of the EMI is the power converter used for high-frequency supply to the inductive coils. The power converter switches and the heat sink with its Printed Circuit Board (PCB) design are predominant in power electronic circuits. This paper facilitates the reduction of EMI without including complex filters. The system is tested for the violated standard SAEJ2954. In addition, the article corroborates precognitive modeling by implementing compensation networks used in IPT applications and their effectiveness in reducing the leakage current caused by the converters and the coils. The paper insights the air gap variation of the coil with the power transfer efficiency and its influence on electromagnetic interferences. The Fast Fourier Transform (FFT) analysis used in PSIM shows leakage current and harmonic reduction with the compensation network and Pulse Width Modulation (PWM) technique. The fabrication model for the front end power supply to the IPT is tested. The electrical noise emission is estimated using predictive modeling. [ABSTRACT FROM AUTHOR]

In recent years, environmental aspects of transport have been at the center of attention for research concerning sustainable development. The most discussed topics comprise vehicle emission production and fuel consumption. These are influenced by many variables and factors. In addition to individual vehicle characteristics and attributes, engine performances, exhaust systems, and their overall construction designs, the terrain and road profile itself have a non-negligible effect on emission production. Road profile parameters can increase or decrease the total vehicle consumption if its potential is utilized correctly. This manuscript discusses the options to reduce road vehicle consumption while accelerating where its velocity is decreased and yet again increased when using the longitudinal terrain profile principle. The physical relations for this subject are presented in the manuscript as well. Based on the data and knowledge achieved, the manuscript then addresses several scenarios in which the fuel consumption of the examined vehicle and an occurrence of certain emission types are examined. Lastly, multiple development trends that can positively affect the specified road vehicle's negative effects on the environment are described. The novel approach of the conducted research consists primarily of the interdisciplinary connection between road transport planning and vehicle traffic study (i.e., negative environmental aspects resulting from road transport can be mitigated not only by assistant devices installed in vehicles, such as catalytic converters, solid particle filters but also by constructing judiciously designed roads). [ABSTRACT FROM AUTHOR]

The integration of machine learning (ML) methods into chemical catalysis is evolving as a new paradigm for cost and time economic reaction development in recent times. Although there have been several successful applications of ML in catalysis, the prediction of enantioselectivity (ee) remains challenging. Herein, we describe a ML workflow to predict ee of an important class of catalytic asymmetric transformation, namely, the relay Heck (RH) reaction. A random forest ML model, built using quantum chemically derived mechanistically relevant physical organic descriptors as features, is found to predict the ee remarkably well with a low root mean square error of 8.0 ± 1.3. Importantly, the model is effective in predicting the unseen variants of an asymmetric RH reaction. Furthermore, we predicted the ee for thousands of unexplored complementary reactions, including those leading to a good number of bioactive frameworks, by engaging different combinations of catalysts and substrates drawn from the original dataset. Our ML model developed on the available examples would be able to assist in exploiting the fuller potential of asymmetric RH reactions through a priori predictions before the actual experimentation, which would thus help surpass the trial and error loop to a larger degree. [ABSTRACT FROM AUTHOR]

In heterogeneous catalysis, reactivity and selectivity are not only influenced by chemical processes occurring on catalytic surfaces but also by physical transport phenomena in the bulk fluid and fluid near the reactive surfaces. Because these processes take place at a large range of time and length scales, it is a challenge to model catalytic reactors, especially when dealing with complex surface reactions that cannot be reduced to simple mean-field boundary conditions. As a particle-based mesoscale method, Stochastic Rotation Dynamics (SRD) is well suited for studying problems that include both microscale effects on surfaces and transport phenomena in fluids. In this work, we demonstrate how to simulate heterogeneous catalytic reactors by coupling an SRD fluid with a catalytic surface on which complex surface reactions are explicitly modeled. We provide a theoretical background for modeling different stages of heterogeneous surface reactions. After validating the simulation method for surface reactions with mean-field assumptions, we apply the method to non-mean-field reactions in which surface species interact with each other through a Monte Carlo scheme, leading to island formation on the catalytic surface. We show the potential of the method by simulating a more complex three-step reaction mechanism with reactant dissociation. [ABSTRACT FROM AUTHOR]

Despite the current boost in the use of electric vehicles to reduce the automotive sector's footprint, combustion vehicles are and will be present in our cities in both the immediate and long term. In this sense, catalytic converters, which are exhaust gas post-treatment systems for vehicle emission control, are critical for complying with increasingly stringent environmental regulations. This work proposes a systematic review to identify the most relevant knowledge regarding the parameters (materials, geometries, and engine conditions), conditions (cold start, oxygen storage, and deactivation), and mathematical models to consider in the design of catalytic converters. The Scopus database contains 283 records related to this review's objective. After applying the inclusion and exclusion criteria, 65 reports were retrieved for evaluation. A table was created to present the results and prepare this manuscript. The evaluation revealed that the following topics were active: the study of non-noble catalyst materials, as well as new substrate materials and geometries, for designing more compact and cost-effective catalytic converters; the development of strategies to improve conversion during cold starts; and the development of accurate and fast estimation models. [ABSTRACT FROM AUTHOR]

Rhodium is one of the scarcest, most valuable, and useful platinum group metals, a strategically important material relied on heavily by automotive and electronics industries. The limited finite natural sources of Rh and exponentially increasing demands on these supplies mean that new sources are being sought to stabilise supplies and prices. Spent nuclear fuel (SNF) contains a significant quantity of Rh, though methods to recover this are purely conceptual at this point, due to the differing chemistry between SNF reprocessing and the methods used to recycle natural Rh. During SNF reprocessing, Rh partitions between aqueous nitric acid streams, where its speciation is complex, and insoluble fission product waste streams. Various techniques have been investigated for Rh recovery during SNF reprocessing for over 50 years, including solvent extraction, ion exchange, precipitation, and electrochemical methods, with tuneable approaches such as impregnated composites and ionic liquids receiving the most attention recently, assisted by more the comprehensive understanding of Rh speciation in nitric acid developed recently. The quantitative recovery of Rh within the SNF reprocessing ecosystem has remained elusive thus far, and as such, this review discusses the recent developments within the field, and strategies that could be applied to maximise the recovery of Rh from SNF. [ABSTRACT FROM AUTHOR]

In general, the structures of Multi-Active Bridge (MAB) converters that can be found in the literature are usually based on voltage converters. However, in some cases, it could be interesting to have a current-fed input due to load characteristics or operation constraints. This leads to a hybrid MAB structure mixing both current-fed and voltage-fed bridges. In this paper, a new hybrid-fed, fully coupled Triple-Active Bridge (TAB) converter topology with two voltage-fed ports and one current-fed port is studied, modelled and controlled. In the first place, a generalized average model (GAM) is developed for this system. After that, a reduced-order model is elaborated in order to simplify the behavioral study and control of this coupled system. A control strategy was also proposed in this paper, based on the developed mathematical model. Simulation results using Matlab/Simulink are presented to validate this study. [ABSTRACT FROM AUTHOR]

In reaction engineering, reactor performance can be improved in many cases by overcoming transport limitations. This requires detailed analyses of transport phenomena in the catalytic beds. Nuclear magnetic resonance (NMR) velocimetry measurements have been utilized for analyzing mass transport of gas flows within opaque monoliths. Comparisons to full-field computational fluid dynamics (CFD) simulations, however, show significant deviations. In this study, polyethylene glycol (PEG) and 3D-printed monoliths including one open-cell foam (OCF) and one honeycomb were used to demonstrate that both operating fluid and monolith morphology influence the achievable signal-to-noise ratio and resolution of NMR data. The velocity profiles measured by NMR in OCF agreed well with full-field CFD simulations with ± 5% deviation. In addition, the similarity between the simulated and experimental velocity fields was quantified by the similarity index, which is 1 for identical images. A mean value of 0.83 was determined for a 10 PPI OCF. Thus, using PEG as the operating fluid and a 10 PPI OCF allows to improve both spatial resolution by 34% and the quality of agreement by 13 percentage points compared to the published results of gas velocimetry within 20 PPI OCF. We further identified and quantified possible sources of deviation between CFD and MRV velocity fields. By limiting our analysis to velocities higher than 45% of the maximum velocity, we could achieve similarity indices of 0.95–0.99. [ABSTRACT FROM AUTHOR]

Dual-active bridge (DAB) converters are receiving increasing attention from researchers as a critical part of the power transmission of energy routers. However, the DAB converter generates a large backflow power in conventional control mode, and when the load is mutated, its output voltage takes longer to return to the reference value accompanied by large fluctuations. To solve the above problems, a hybrid strategy is proposed in this paper to optimize the converter. The mathematical models of the transmitted power and the backflow power were firstly derived through in-depth analysis of the DAB converter under extended-phase-shift (EPS) modulation, and the suppression of the backflow power was performed according to the improved Lagrange method utilized in the obtained results. Moreover, considering the poor dynamic characteristics of DAB converters under PI control, according to the state space average model of output voltage in the paper, a model prediction control equation is established to improve the dynamic response of the converter by predicting the output voltage value at the next moment. The simulation results verify the effectiveness of the optimization strategy presented in the text. [ABSTRACT FROM AUTHOR]

A stable solid electrolyte interphase (SEI) layer is crucial for lithium metal anode (LMA) to survive in long‐term cycling. However, chaotic structures and chemical inhomogeneity of natural SEI make LMA suffering from exasperating dendrite growth and severe electrode pulverization, which hinder the practical application of LMAs. Here, we design a catalyst‐derived artificial SEI layer with an ordered polyamide‐lithium hydroxide (PA‐LiOH) bi‐phase structure to modulate ion transport and enable dendrite‐free Li deposition. The PA‐LiOH layer can substantially suppress the volume changes of LMA during Li plating/stripping cycles, as well as alleviate the parasitic reactions between LMA and electrolyte. The optimized LMAs demonstrate excellent stability in Li plating/stripping cycles for over 1000 hours at an ultra‐high current density of 20 mA cm−2 in Li||Li symmetric cells. A high coulombic efficiency up to 99.2 % in Li half cells in additive‐free electrolytes is achieved even after 500 cycles at a current density of 1 mA cm−2 with a capacity of 1 mAh cm−2. [ABSTRACT FROM AUTHOR]

A stable solid electrolyte interphase (SEI) layer is crucial for lithium metal anode (LMA) to survive in long‐term cycling. However, chaotic structures and chemical inhomogeneity of natural SEI make LMA suffering from exasperating dendrite growth and severe electrode pulverization, which hinder the practical application of LMAs. Here, we design a catalyst‐derived artificial SEI layer with an ordered polyamide‐lithium hydroxide (PA‐LiOH) bi‐phase structure to modulate ion transport and enable dendrite‐free Li deposition. The PA‐LiOH layer can substantially suppress the volume changes of LMA during Li plating/stripping cycles, as well as alleviate the parasitic reactions between LMA and electrolyte. The optimized LMAs demonstrate excellent stability in Li plating/stripping cycles for over 1000 hours at an ultra‐high current density of 20 mA cm−2 in Li||Li symmetric cells. A high coulombic efficiency up to 99.2 % in Li half cells in additive‐free electrolytes is achieved even after 500 cycles at a current density of 1 mA cm−2 with a capacity of 1 mAh cm−2. [ABSTRACT FROM AUTHOR]

Inductive power transfer (IPT) technology is a promising solution for charging the electric vehicles (EVs) by enabling an EV to charge its energy storage system (battery) without any connecting wires through magnetic coupling. This paper proposes a new receiver design named Hollow Solenoid receiver that is compatible with the standard double-D transmitter defined by the SAE J2954 standard. A deep design analysis for the proposed Hollow Solenoid receiver is presented to define the optimum design parameters for coil (inductances, number of turns, dimensions, wires, etc.) and ferrite core (dimensions, number, arrangement, etc.). Several WPT3 (11.1kVA) solenoid receiver (SR) designs were presented and analyzed based on efficiency, weight, size, volume, and cost. The performance of the proposed SR was compared with the global Double-D receiver (DDR) presented by the SAE J2954 standard under different lateral and rotational alignment and loading conditions considering coupling factor, transmission power and efficiency, and stray electromagnetic fields (EMFs). The entire IPT system including coils, compensation network, power converters, controls, and battery load was modeled and analyzed for both SR and DDR coils. The results reveal that the proposed SR is compatible with the global DD transmitter at different alignment and loading conditions and is able to transmit the desired power (11 kW) at an efficiency > 85%. Hollow SR design shows the highest efficiency and lowest size, weight, and cost compared to DDR and other designs. [ABSTRACT FROM AUTHOR]