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Solar-driven semiconductor photocatalysts are highly appealing in applications of environmental remediation and energy conversion. However, photocatalytic reactions, particularly oxygen evolution reaction (OER), are often constrained by the swift recombination of electron–hole pairs, thereby resulting in low reaction efficiency. Although it is effective to separate charge carriers by constructing heterojunctions to form built-in electric field, the lattice mismatch and inefficient interlayer charge transfer of heterojunctions in the photocatalysts limit their further development. Here, we propose a new strategy by constructing an internal electric field for OER through an individual piezoelectric two-dimensional material. The results indicate that the piezoelectric effect regulates the electronic structure, reduces bandgap, improves light absorption efficiency, and that the displacement of positive and negative charge centers is the key factor in the enhanced OER. This research indicates the feasibility of combining piezoelectric properties of two-dimensional materials with OER (1.19 eV), providing new insights and guidance for applying the piezoelectric effect in the OER and opening up a way to promote efficient separation of charge carriers. [ABSTRACT FROM AUTHOR]

Physical processes involving hot electrons, including their generation, transport, injection, and relaxation, have been an extensive area of research. The most widely utilized method for actuating the creation of hot electrons involves the excitation of plasmonic modes followed by their non-radiative decay, channeling the energy into these energetic carriers. Since plasmonics has already evolved into a mature field of scientific exploration, active plasmonic devices serve as an ideal platform to study hot-electron physics. In this Perspective article, we will provide the reader with a comprehensive outline of the physics underlying hot-electron dynamics. Emphasis will be placed on the characteristic timescales involved with the lifecycle of hot electrons, the generation and decay mechanisms of surface plasmon-induced hot electrons, and the material platforms suitable for such a study. Then, we will move on to discuss different temperature models used to explain the evolution of hot electrons and the changes in the optical properties of the materials they are generated in or injected into. Finally, we will focus on some of the interesting optical phenomena occurring at ultrafast timescales mediated by hot-carrier dynamics. Such a discussion is expected to incorporate valuable insights into our understanding of the synergistic relationship between hot-electron dynamics and active plasmonics, thereby paving the way for novel applications involving optoelectronics and energy conversion. [ABSTRACT FROM AUTHOR]

Recent developments in materials manufacturing has allowed researchers to engineer unique wave-matter interactions at the nano-scale. These interactions foster unique and coupled modes of thermal, optical, electrical, and acoustic energy transport and conversion. This study addresses the sensitivity of the static ϵ 0 and complex ϵ ~ (ω) = ϵ 1 (ω) + i ϵ 2 (ω) dielectric constant due to changes in pressure (P), volume (V), and temperature (T). General β -sensistivity relations are derived based on traditional Drude and Lorentz oscillator models. Then, these sensitivity relations are compared to literature d ln ⁡ ϵ i / d T and d ln ⁡ ϵ i / d ln ⁡ V data for various metals, dielectric insulators, and semiconductor materials. For example, the effects of isotropic strain on ϵ (ω) are found to have two common contributions: the frequency dependence of the dielectric dispersion (d ln ⁡ ϵ / d ln ⁡ ω) and key vibrational-mode Grüneisen parameters (γ i = − d ln ⁡ ω i / d ln ⁡ V). Because these sensitivity relations are dictated by the various electronic, optical, and lattice Grüneisen parameters, a comprehensive listing of mode Grüneisen parameters and coupled property data are provided for materials ranging from metals to semiconductors to polymers to dielectric insulators such as BaTiO 3. In most cases, the developed sensitivity relations are consistent with published isotropic strain derivative data. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new approach for constructing broadband rectifiers from resonant-type in-plane spin-torque diodes (STDs). The intrinsic bandwidth of such STDs constrained by the ferromagnetic resonance linewidth of the corresponding magnetic tunnel junction's is relatively narrow, which is a significant limitation. To address this issue, we propose the implementation of an array of these STDs, each with a distinct resonance frequency. By ensuring that the frequency difference between adjacent STDs is smaller than their individual bandwidths, we achieve a device capable of rectifying signals over a much wider frequency range. To verify the effectiveness of our approach, we have performed analytical calculations based on the Landau–Lifshitz–Gilbert equation with the Slonczewski term, complemented by macrospin modeling and full-scale micromagnetic simulations to account for thermal fluctuations and local magnetization inhomogeneities. Our results demonstrate that an STD array can effectively function as a broadband energy harvester, maintaining near-constant rectification efficiency across a broad frequency range. This research establishes the groundwork for the development of broadband energy harvesters based on STD arrays, with potential applications in various fields requiring efficient energy conversion across a wide frequency spectrum. [ABSTRACT FROM AUTHOR]

Thermophotovoltaic (TPV) systems can be used to harvest thermal energy for thermoelectric conversion with much improved efficiency and power density compared with traditional photovoltaic systems. As the key component, selective emitters (SEs) can re-emit tailored thermal radiation for better matching with the absorption band of TPV cells. However, current designs of the SEs heavily rely on empirical design templates, particularly the metal-insulator-metal (MIM) structure, and lack of considering the overall performance of TPV systems and optimization efficiency. Here, we utilized a deep reinforcement learning (DRL) method to perform a comprehensive design of a 2D square-pattern metamaterial SE, with simultaneous optimization of material selections and structural parameters. In the DRL method, only the database of refractory materials with gradient refraction indexes needs to be prepared in advance, and the whole design roadmap will automatically output the SE with optimal Figure-of-Merit (FoM) efficiently. The optimal SE is composed of a novel material combination of TiO2, Si, and W substrate, with its thickness and structure precisely optimized. Its emissivity spectra match well with the external quantum efficiency curve of the GaSb cell. Consequently, the overall performance of TPV is significantly enhanced with an output power density of 5.78 W/cm2, an energy conversion efficiency of 38.26%, and a corresponding FoM of 2.21, surpassing most existing designs. The underlying physics of optimal SE is explained by the coupling effect of multiple resonance modes. This work advances the practical application potential of TPV systems and paves the way for addressing other multi-physics optimization problems and metamaterial designs. [ABSTRACT FROM AUTHOR]

This study explores the enhancement of thermoelectric response in a zigzag chain through irradiation with arbitrarily polarized light. The irradiation induces changes in hopping strengths, creating an asymmetric transmission profile around the Fermi energy, which is a crucial factor for achieving a higher figure of merit (FOM). Specific light configurations result in an FOM exceeding unity. We employ the Floquet–Bloch ansatz and minimal coupling scheme to model the irradiation effect, with transport properties evaluated using Green's function technique within the Landauer–Büttiker formalism. The investigation covers electrical conductance, thermopower, and thermal conductance due to electrons and phonons. Our research deepens understanding and opens avenues for tailoring nanostructures to fine-tune thermoelectric properties, advancing highly efficient energy conversion devices exploiting irradiation effects. [ABSTRACT FROM AUTHOR]

The entropy change causing dipolar depolarization is proposed as an origin of electrical power generation in triboelectric generators using polar materials. Rubbing mechanically forces permanent dipoles in materials to become orientationally ordered, establishing a low entropy state with an initial dipolar polarization P 0. In this state, the electric field within the materials is zero, but a nonzero Helmholtz free energy F = F 0 = P 0 2 2 (C s − C ∞) arises from the entropy contribution (C s , static capacitance; C ∞ , capacitance at high frequency). Consequently, this state is energetically unstable and undergoes a spontaneous transition into a disordered high entropy state with F < F 0 , resulting in the establishment of a non-zero electric field. Through this process, the energy bounded in materials as the entropy component of free energy is converted, and the electrical energy becomes F 0 η with η = 1 − C ∞ C s (0 < η < 1). Electrical circuit analysis shows that this energy conversion process can be well represented by introducing a virtual resistance R p = τ C s − C ∞ (τ , dipolar relaxation time). This suggests that the entropy change in finite time τ serves as the origin of electrical power generators. Under the matching condition τ = C s R , the power spectrum at the load is best aligned with that at the generator, maximizing the power transmission. The results presented here serve as a basis for understanding the principle of electric power transmission in triboelectric generators through dipolar depolarization. [ABSTRACT FROM AUTHOR]

Photocurrent measurements are widely used to study the intrinsic optoelectronic properties of semiconductors, such as photocarrier generation efficiency and carrier mobility, as well as evaluate the performance of optoelectronic devices, such as solar cells and photodetectors. Interferometric spectroscopy precisely measures optical properties and gathers optical spectra information on semiconductors. Consequently, photocurrent-based interferometric measurements, with high signal-to-noise ratios, high resolution, and broad frequency bandwidths, can probe the energy distributions of low-density defects and impurities and investigate charge transport in materials and devices. Here, we demonstrate that photocurrent interference spectroscopy reveals the intrinsic properties of solar-cell materials: bulk crystals of GaAs and halide perovskite, and thin films of halide perovskite and quantum dot. We show that homodyne interference spectroscopy of photocurrent can monitor low-density localized states in semiconductors and that it can be used in combination with other spectroscopy techniques, such as photoluminescence measurements, to provide a deep understanding of photocurrent generation processes. Furthermore, we show that heterodyne interference spectroscopy of photocurrent can be used to investigate the frequency dependence of material parameters, such as the dielectric constant, absorption coefficient, and reflectance. As an application, we used interference spectroscopy of photocurrent to show the impact of multiexcitons on the photoabsorption and photocarrier generation processes in quantum dot solar cells. Finally, we used it to reveal the distinctive spectral characteristics at the band edge of a halide perovskite, which is considered to be an exceptional solar-cell material with high energy conversion efficiency. [ABSTRACT FROM AUTHOR]

The chemical flexibility of metal-organic frameworks (MOFs) offers an ideal platform to tune structure and composition for specific applications, from gas sensing to catalysis and from photoelectric conversion to energy storage. This variability gives rise to a large configurational space that can be efficiently explored using high-throughput computational methods. In this work, we investigate from first principles the structural and electronic properties of MOF-5 variants obtained by replacing Zn with Be, Mg, Cd, Ca, Sr, and Ba and by functionalizing the originally H-passivated linkers with CH3, NO2, Cl, Br, NH2, OH, and COOH groups. To build and analyze the resulting 56 structures, we employ density-functional theory calculations embedded in an in-house developed library for automatized calculations. Our findings reveal that structural properties are mainly defined by metal atoms and large functional groups, which distort the lattice and modify coordination. The formation energy is largely influenced by functionalization and enhanced by COOH and OH groups, which promote the formation of hydrogen bonds. The charge distribution within the linker is especially influenced by functional groups with electron-withdrawing properties, while the metal nodes play a minor role. Likewise, the bandgap size is crucially determined by ligand functionalization. The smallest gaps are found with NH2 and OH groups, which introduce localized orbitals at the top of the valence band. This characteristic makes these functionalizations particularly promising for the design of MOF-5 variants with enhanced gas uptake and sensing properties. [ABSTRACT FROM AUTHOR]

An analytical device physics model is presented for determining the energy conversion efficiency of semiconductor nanowire array-based radial (core–shell) p-i-n junction betavoltaic cells for two- and three-dimensional radioisotope source geometries. Optimum short-circuit current density J sc , open-circuit voltage V oc , fill factor F F , and energy conversion efficiency η are determined for various nanowire properties, including dopant concentration, nanowire length, core diameter, and shell thickness, for Si, GaAs, and GaP material systems. A maximum efficiency of 8.05 % was obtained for GaP nanowires with diameter 200 nm (p-core diameter, i-shell, and n-shell thicknesses of 24, 29.4, and 58.6 nm, respectively), length 10 μ m , acceptor and donor concentrations of 10 19 and 5 × 10 18 cm − 3 , respectively, and a 3D source geometry. [ABSTRACT FROM AUTHOR]

Efficient thermoelectric energy conversion at the nanoscale could power the Internet of Things and cool nanoelectronic circuits and improve the performance of quantum applications. Width-modulated nanowaveguides are suitable for these purposes because their thermoelectric efficiency can be geometrically tuned and integrated into the nanoelectronics industry processes. They are attracting increasing research interest stimulated by theoretical predictions for exceptional performance. To validate their potential, a better understanding of the effect of width modulation on thermoelectric efficiency is needed. So far, it is considered that (a) the thermoelectric efficiency increases monotonically with increasing width-mismatch due to decreasing phonon thermal conduction taking place without significantly affecting electron transport, (b) width-mismatch dominates the effect of width modulation in transport, and (c) phonons play the main role in increasing the thermoelectric efficiency. Here, we demonstrate counterevidence based on an investigation of the effect of width modulation on electrons so far overlooked. We reveal that (a) the thermoelectric efficiency varies non-monotonically with the modulation mismatch due to quantum effects on electron transport, (b) the modulation mismatch is quantified by the size-mismatch of the modulation rather than by the width-mismatch, and (c) it is electrons rather than phonons that play the main role in optimizing width modulation for maximum thermoelectric efficiency when quantum effects dominate. Our findings indicate that research should reorient from large width-mismatch toward optimal modulation-mismatch width-modulated nanostructures to enhance thermoelectric efficiency due to quantum effects. Our work provides new insight for designing nanowaveguides for efficient thermoelectric energy conversion at the nanoscale. [ABSTRACT FROM AUTHOR]

Roughly, 50% of primary energy worldwide is rejected as waste heat over a wide range of temperatures. Waste heat above 573 K has the highest Carnot potential (> --> 50 %) to be converted to electricity due to higher Carnot efficiency. Thermoelectric (TE) materials have gained significant attention as potential candidates for efficient thermal energy conversion devices. Silicon nanowires (SiNWs) are promising materials for TE devices due to their unique electrical and thermal properties. In this study, we report the successful fabrication of high-quality double-sided SiNW arrays using advanced techniques. We engineered the double-sided structure to increase the surface area and the number of TE junctions, enhancing TE energy conversion efficiency. We also employed non-agglomeration wire tip engineering to ensure uniformity of the SiNWs and designed effective Ohmic contacts to improve overall TE efficiency. Additionally, we post-doped the double-sided SiNW arrays to achieve high electrical conductivity. Our results showed a significant improvement in the TE performance of the SiNW array devices, with a maximum figure-of-merit (ZT) value of 0.24 at 700 K, fabricated from the single SiNW with ZT of 0.71 at 700 K in our previous work [Yang et al., Nat. Commun. 12(1), 3926(2021)]. [ABSTRACT FROM AUTHOR]

Direct thrust measurements are performed on a circular waveguide electron cyclotron resonance (ECR) thruster working at 5.8 GHz using a pendulum thrust balance with mechanically amplified displacement. Thrust levels between 1 and 3.5 mN are found for power levels in the range of 60–350 W and xenon flow rate between 2 and 8 SCCM. A maximum thrust efficiency of 3.5% is reached at 2 SCCM and 60 W. Plasma plume diagnostics are used to estimate the thruster partial efficiencies to understand the main losses, and to perform a comparative analysis between directly and indirectly measured thrust. Results suggest that the low energy conversion efficiency and propellant utilization efficiency (< 6.4 % and < 53%, respectively) are the key factors spoiling the ECR thruster performance. Finally, retarding potential analyzer measurements show the presence of energetic electrons with energy tail up to about 300 eV. [ABSTRACT FROM AUTHOR]

The choice of exchange functional is a critical factor in determining the energy bandgap of semiconductors. Ab initio calculations using different exchange functionals, including the conventional generalized-gradient approximation (GGA) functionals, meta-GGA functionals, and hybrid functionals, show significant differences in the calculated energy bandgap for semiconducting half-Heusler compounds. These compounds, which have 18 valence electrons per unit cell, are of great interest due to their thermoelectric properties, making them suitable for energy conversion applications. In addition, accounting for electronic correlations using the G W method also affects the calculated energy bandgaps compared to standard GGA calculations. The variations in calculated energy bandgaps are specific to each material when using different functionals. Hence, a detailed investigation of the electronic properties of each compound is necessary to determine the most appropriate functional for an accurate description of the electronic properties. Our results indicate that no general rules can be established and a comparison with experimental results is required to determine the most appropriate functional. [ABSTRACT FROM AUTHOR]

Pandit[1] provides a review on the application of magic angle spinning nuclear magnetic resonance (NMR) spectroscopy and related techniques, with which it is possible to access the motion of proteins, pigments, and lipids on sub-nanoseconds to millisecond timescales on very different length scales ranging from solubilized complexes to whole cells. Remarkably, the spectral density includes 50 high-frequency vibrational modes per pigment, besides a low-frequency part characterizing the pigment-protein coupling. Using this technique, excitation energy transfer between the bacteriochlorophyll a pigments of the LH2 complex of purple bacteria is studied. Two important points dealt with in the present Special Topic issue on "Photosynthetic Light-Harvesting and Energy Conversion" are the following: (i) Pigment-protein complexes undergo conformational transitions on many different timescales that include transitions between functionally relevant modes of light harvesting and photoprotection. [Extracted from the article]

An innovative electromagnetic energy harvester was developed using a compact four-ring single-resistor unit cell. To achieve efficient conversion of electromagnetic waves into electricity, we integrated the high-performance Bi2Te3 thermoelectric material onto the load resistor. Remarkably, this unit cell exhibits exceptional energy harvesting capabilities at a frequency of 5.8 GHz while maintaining polarization insensitivity. Through comprehensive analysis, we evaluated the energy harvesting efficiencies, power loss distribution, and current density distribution. Additionally, we investigated the impact of incident power on the unit cell's temperature and energy conversion efficiencies. To enhance energy concentration on the load, we ingeniously designed an "L-shaped" metal through-hole structure within the four-ring single-resistor unit cell. Our results demonstrate that the four-ring single-resistor unit cell achieves an impressive harvesting efficiency of 94.5% at 5.8 GHz, with a thermal conversion efficiency of 43.3 °C/W, an electrical conversion efficiency of 0.23 mV/°C, and an electrical response rate of 9.4 mV/W. Notably, when subjected to a power input of 7 W, the unit cell produces an output voltage of 65.9 mV, and its theoretical maximum output power reaches 180 mW. [ABSTRACT FROM AUTHOR]

In this work, we study thermalization between two bodies separated by a vacuum gap by coupling the non-Fourier behavior of the materials with the radiative heat transfer in the near-field. Unlike the diffusion-type temperature profile, in non-Fourier materials, the temperature behaves as a wave, changing the thermalization process. Due to the temperature profile induced by the coupling with conduction, we show that the radiative heat flux exchanged between the two bodies differs from the Fourier case and exhibits transient temperature effects at the onset of the thermalization process. These results have important implications in nanoscale thermal management, near-field solid-state cooling, and nanoscale energy conversion. [ABSTRACT FROM AUTHOR]

Tailoring surface components and nanostructures via integration of dual transition metal heteroatoms is a highly effective technique for the design and synthesis of electrocatalysts with superior performance. In this study, we report WS₂/WO₃ nanostructure enriched with sulphur and oxygen vacancies, embedded within laser-induced graphene (LIG) as carbon support, to improve alkaline and seawater splitting applications for the oxygen evolution reaction (OER). The LIG-WS₂/WO₃ nanohybrid demonstrates high OER activity and improved stability due to the synergistic interaction between LIG, WS₂, WO₃, and optimized proportion of sulphur and oxygen vacancies, which facilitates efficient charge transfer, reduces recombination losses and allows significant tuning of various electrocatalytic parameters as a function of annealing temperature. The optimized sample, LWSO@450, exhibits excellent electrocatalytic activity with a low overpotential of 350 mV at a current density of 50 mA/cm2 and an exceptionally low Tafel slope of 33 mV/decade in an alkaline medium. Moreover, the high electrochemically active surface area of 134 cm2, mass activity of 60 A/g, and turnover frequency of 0.012 s⁻1 indicate a substantial number of active sites. These findings highlight the considerable potential of this catalyst in various electrochemical domains, particularly in energy conversion, and other renewable energy systems, due to its cost-effectiveness, availability, and scalability. [Display omitted] • WS 2 /WO 3 nanohybrids incorporated laser induced graphene for OER. • Annealing controlled phase transformation of WS 2 to WO 3. • Optimized sample LWSO@450 exhibits 350 mV at a current density of 50 mA/cm2. • Tafel slope of 33 mV/decade in alkaline medium. [ABSTRACT FROM AUTHOR]

The combustion process is an indispensable energy conversion step in modern industry and energy production. Especially in high-performance engines and energy conversion systems, understanding and controlling the combustion process is critical to improving efficiency and reducing environmental pollution. As a key component of mechanical systems, the combustion characteristics of lubricants at high temperatures and pressures have a direct impact on system performance and emissions. This study investigated the combustion characteristics of lubricant films in an ammonia-methane premixed environment using Planar Laser-Induced Fluorescence (PLIF) and Planar Laser-Induced Incandescence (PLII). It focused on the effects of varying ammonia concentrations on the emission of soot and polycyclic aromatic hydrocarbons (PAHs) in the constant volume combustion vessel. Experiments varied the ammonia-to-methane molar ratios, initial oil film thickness, and base oil type to study their influence on the lubricant combustion characteristics. Results indicated that ammonia significantly reduced soot formation by altering the dynamics of NH* and OH* and impacting PAH distribution. For the lubricating oil soot formation factors, the increase of the initial mean oil film thickness was more obvious for the promotion of soot formation, the increase of the unsaturated hydrocarbon content in the oil film also promoted the generation of carbon soot to a certain extent, and the initial flame energy ratio had the least influence on the promotion of soot formation. Overall, the study contributed to the understanding of the formation mechanism of soot caused by lubricating oil in zero-carbon and low-carbon blended atmospheres and provided a new insight into the interaction between nitrogen-containing zero-carbon fuels and large-carbon-number hydrocarbons, which is of great significance for controlling soot emissions from engines under zero-carbon fuel blending. • Ammonia alters NH and OH dynamics, reducing PAHs and soot formation. • Film thickness, lubricant type, NH3:CH4 ratio affect pool fire combustion. • New insights for engine soot emission control under zero/low-carbon fuels. [ABSTRACT FROM AUTHOR]

The adhesion of gases to the electrodes is a major reason for reductions in energy efficiency, and hinders the production of hydrogen in alkaline water electrolysis (AWE). The development of an effective solution to this problem will be crucial for the design and optimization of AWE. In this paper, we present a novel structure for an electrolyser in which baffles are inserted into the channel. The flow process of the electrolyte and the electrochemical reactions in the electrolyser with the new structure are simulated, and the effects of the added baffles on the distribution of the gas phase production and the efficiency of energy conversion are analysed. Several important structural parameters are considered, such as the angle, number and length of the baffles, and corresponding numerical calculations are performed. In order to carry out a comprehensive evaluation of the performance of each electrolyser, the energy efficiency of AWE is evaluated and the current effect, ohmic overvoltage effect and bubble overvoltage effect caused by gas adhesion are quantitatively investigated. The results show that the flow of the electrolyte can be divided into three phases when baffles are added to the channel of the electrolyser, and that the baffles play a crucial role in both the transition phase and the full development phase. The maximum reduction in gas coverage at the electrodes reaches 60% and the maximum increase in energy efficiency reaches more than 3.0% with the addition of baffles. The addition of baffles has significant effects on the current and ohmic overpotential, and the balance between the gas coverage and ohmic overpotential can allow the maximum energy efficiency of the AWE to be achieved. [Display omitted] • A novel design for an electrolyser with baffles optimises the electrolyte flow. • The mechanism of transport in an electrolyser with baffles is analysed. • The effects of the angle, number and location of baffles are studied. • The thermodynamics performance of electrolyser is evaluated. [ABSTRACT FROM AUTHOR]

The solar‐driven photorechargeable zinc‐ion batteries have emerged as a promising power solution for smart electronic devices and equipment. However, the subpar cyclic stability of the Zn anode remains a significant impediment to their practical application. Herein, poly(diethynylbenzene‐1,3,5‐triimine‐2,4,6‐trione) (PDPTT) was designed as a functional polymer coating of Zn. Theoretical calculations demonstrate that the PDPTT coating not only significantly homogenizes the electric field distribution on the Zn surface, but also promotes the ion‐accessible surface of Zn. With multiple N and C=O groups exhibiting strong adsorption energies, this polymer coating reduces the nucleation overpotential of Zn, alters the diffusion pathway of Zn2+ at the anode interface, and decreases the corrosion current and hydrogen evolution current. Leveraging these advantages, Zn‐PDPTT//Zn‐PDPTT exhibits an exceptionally long cycling time (≥4300 h, 1 mA cm−2). Zn‐PDPTT//AC zinc‐ion hybrid capacitors can withstand 50,000 cycles at 5 A/g. Zn‐PDPTT//NVO zinc‐ion battery exhibits a faster charge storage rate, higher capacity, and excellent cycling stability. Coupling Zn‐PDPTT//NVO with high‐performance perovskite solar cells results in a 13.12 % overall conversion efficiency for the photorechargeable zinc‐ion battery, showcasing significant value in advancing the efficiency and upgrading conversion of renewable energy utilization. [ABSTRACT FROM AUTHOR]

Anionic chemistry modulation represents a promising avenue to enhance the electrochemical performance and unlock versatile applications in cutting‐edge energy storage devices. Herein, we propose a methodology that involves anionic chemistry of carbonate anions to tailor the electrochemical oxidation‐reduction reactions of bismuth (Bi) electrodes, where the conversion energy barrier for Bi (0) to Bi (III) has been significantly reduced, endowing anionic full batteries with enhanced electrochemical kinetics and chemical self‐charging property. The elaborately designed batteries with an air‐switch demonstrate rapid self‐recharging capabilities, recovering over 80 % of the electrochemical full charging capacity within a remarkably short timeframe of 1 hour and achieving a cumulative self‐charging capacity of 5 Ah g−1. The aqueous self‐charging battery strategy induced by carbonate anion, as proposed in this study, holds the potential for extending to various anionic systems, including seawater‐based Cl− ion batteries. This work offers a universal framework for advancing next‐generation multi‐functional power sources. [ABSTRACT FROM AUTHOR]

Transition-metal hydroxides are a category of earth-abundant and stable electrocatalysts for energy storage and conversion devices involving sluggish oxygen evolution reaction (OER). Understanding dynamic evolution at the solid/liquid interface of transition-metal hydroxides is crucial for the rational design of high-performance OER electrocatalysts. This study implemented in situ electrochemical atomic force microscopy (EC-AFM) to directly image the dynamic structural evolution of α-Co(OH)2 platelets during the electrochemical OER. Reconstruction of α-Co(OH)2, accompanied by ion insertion from the electrolyte, results in a volume expansion, which can be well confirmed from the X-ray diffraction patterns. Our findings are important for the fundamental understanding of transition-metal hydroxide oxygen-evolution catalysts, illustrating the dynamic nature of Co-based nanostructures under electrochemical conditions. [ABSTRACT FROM AUTHOR]

Thermal plasma-driven dry reforming of methane (DRM) has gained increased attention in recent years due to its high conversion and energy conversion efficiency (ECE). Recent experimental work investigated the performance of a pure CO2 plasma with post-plasma CH4 injection. The rationale behind this strategy is that by utilizing a pure CO2 plasma, all plasma energy can be used to dissociate CO2, while CH4 reforming proceeds post-plasma in the reforming reactor with residual heat, potentially improving the energy efficiency compared to injecting both CO2 and CH4 into the plasma. To assess whether post-plasma CH4 injection indeed improves the DRM performance, we developed a chemical kinetics model describing the post-plasma conversion process. We first validated our model by reproducing the experimental results of the pure CO2 plasma with post-plasma CH4 injection. Subsequently, we compared both strategies: injecting only CO2 inside the plasma while injecting CH4 post-plasma, vs. classical plasma-based DRM. Our modeling results indicate that below specific energy inputs (SEI) of 220 kJ mol-1, the total conversion slightly improves (ca. 5%) with the first strategy. However, the ECE is slightly lower due to the low H2 selectivity caused by substantial H2O formation. The highest conversion and ECE are obtained at SEI values of 240-280 kJ mol-1, where both strategies yield nearly identical results, indicating the limited potential of improving the performance of DRM by pure CO2 plasma with post-plasma CH4 injection. Nevertheless, the approach is still very valuable to allow higher CH4/CO2 ratios without problems of coke formation within the plasma, and thus, to improve plasma stability and reach higher syngas ratios, which is more useful for further Fischer-Tropsch or methanol synthesis. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal Chemical Society Reviews. It highlights various articles and reviews on topics such as biomedical SERS, interfacial chemistry in multivalent aqueous batteries, chiral electrocatalysis, nanodrug discovery, small-molecule fluorescent probes, advanced materials for micro/nanorobotics, flexible thermoelectrics, cellulose-based materials, electrochemical CO2 reduction, and metal-organic frameworks for organic transformations. The journal aims to connect the world with the chemical sciences and is published by The Royal Society of Chemistry. [Extracted from the article]

With the increasing demand for energy and the climate challenges caused by the consumption of traditional fuels, there is an urgent need to accelerate the adoption of green and sustainable energy conversion and storage technologies. The integration of flexible thermoelectrics with other various energy conversion technologies plays a crucial role, enabling the conversion of multiple forms of energy such as temperature differentials, solar energy, mechanical force, and humidity into electricity. The development of these technologies lays the foundation for sustainable power solutions and promotes research progress in energy conversion. Given the complexity and rapid development of this field, this review provides a detailed overview of the progress of multifunctional integrated energy conversion and storage technologies based on thermoelectric conversion. The focus is on improving material performance, optimizing the design of integrated device structures, and achieving device flexibility to expand their application scenarios, particularly the integration and multi-functionalization of wearable energy conversion technologies. Additionally, we discuss the current development bottlenecks and future directions to facilitate the continuous advancement of this field. [ABSTRACT FROM AUTHOR]

For the fiberglass industry making E‐Glass fiber products predominantly, reduction in glass batch melting energy can be achieved by using alternative raw materials that improve the kinetics of the batch‐to‐melt (BtM) conversion process. The present study evaluates the effects of the following five types of natural silicate minerals: kaolin (comprising low [<5 wt%] and high [>50 wt%] “free” quartz), pyrophyllite, anorthosite, and wollastonite, on the BtM conversion process using a reference commercial E‐Glass composition. The study used isothermal heat treatment of individual silicate minerals and batch samples containing them, infrared spectroscopy, powder x‐ray diffraction, and differential scanning calorimetry (DSC) to characterize the stages of the BtM conversion process in detail. Based on the results of this study, a simplified reaction scheme or mechanism is proposed to account for the effect of batch chemistry on the BtM kinetics, namely, “free SiO2” + “free CaO” → CaSiO3 controls the kinetics of the batch melting. Relative to the E‐Glass control batch made using kaolin, sand, and limestone, the DSC tests showed the benefits of using pyrophyllite (replacing kaolin and sand), anorthosite (replacing kaolin and some limestone), and wollastonite (replacing limestone) in lowering the BtM conversion energy (from room temperature [RT] to 1200°C) between 20% and 50%. [ABSTRACT FROM AUTHOR]

This study investigates the flow dynamics and energy losses of Tesla turbines using Computational Fluid Dynamics with OpenFOAM. Our goal is to identify the main sources of energy loss. Four main sources of energy loss were identified. The most significant loss occurred during the conversion of pressure energy to kinetic energy, estimated to range from 88% $88 \% $ to 64% $64 \% $ of the total energy. Energy losses due to leaks between the rotor and the casing were also quantified, ranging from 4.97% $4.97 \% $ to 7.95% $7.95 \% $ of the kinetic energy at peak efficiency points. Design modifications, such as incorporating a nozzle at the entrance of the turbine, can improve efficiency. These findings highlight specific areas for efficiency improvement, offering opportunities for improved turbine design and integration into energy‐generation systems. [ABSTRACT FROM AUTHOR]

ABSTRACT This article describes an energy‐efficient, low‐power CMOS temperature sensor suitable for portable applications. The sensor's front‐end circuitry is designed with a reference voltage (VREF$$ {}_{REF} $$), complementary to absolute temperature (CTAT) voltage (VCTAT$$ {}_{CTAT} $$), and ramp voltage generators. The ramp voltage (Vcap$$ {}_{cap} $$) is produced by utilizing a current reference circuit. The ramp voltage is compared with independent and temperature‐dependent voltages to perform the voltage‐to‐frequency conversion. Conversion from frequency to digital output is achieved through an asynchronous counter with an on‐chip oscillator. The proposed design is realized in a 0.18‐μ$$ \upmu $$m CMOS technology and attains a power usage of 604.4 nW at 27°C with an operating voltage of 0.5 V. Furthermore, it obtains an inaccuracy of +0.71/−0.73°C over −40°C to 125°C temperature range with an active area of 0.025 mm2. Moreover, the designed sensor circuit offers a resolution of 0.17°C with an energy conversion of 96.7 pJ. [ABSTRACT FROM AUTHOR]

Free-piston engine linear generator (FPELG) is an innovative energy conversion device, offering multifuel adaptability and a simple structure. With the piston motion characteristics of FPELGs strongly correlated with the combustion process, the diverse combustion processes associated with various fuels lead to distinct piston dynamics and in-cylinder combustion characteristics. Therefore, this paper proposes a coupled simulation and iterative computation approach, integrating a zero-dimensional dynamic model with a multi-dimensional computational fluid dynamic model, then quantitatively analyses the piston dynamics and engine combustion characteristics of FPELGs using four typical hydrogen-rich fuels. The result reveals that hydrogen- and methane-fuelled FPELGs exhibit the highest and lowest operating frequencies, respectively. Furthermore, hydrogen-fuelled FPELGs showcase the highest peak pressure and temperature in-cylinder, the shortest combustion duration of the free-piston engine, the highest peak heat release rate, increased diffusion in the region of elevated temperature in-cylinder, and the lowest concentration of nitrogen oxide emissions. • The piston dynamics and combustion characteristics of FPELG with hydrogen-rich fuel are quantitatively analysed. • The coupled simulation and iterative computation approach that integrates a zero-dimensional dynamic model with a multi-dimensional computational fluid dynamic model is proposed. • The unique benefits of FPELGs operated with hydrogen-rich fuels are elucidated. [ABSTRACT FROM AUTHOR]

Photocatalysis and electrocatalysis have emerged as promising technologies for addressing the energy crisis and environmental issues. However, the widespread application of these technologies is hampered by the challenge of scaling up the production of photo/electrocatalysts that are not only highly active and stable but also cost‐effective and environmentally benign. This review delves into the latest advancements in the large‐scale synthesis of photo/electrocatalysts. The factors to be considered in the large‐scale production of catalysts are discussed first. The synthesis methods for batch preparation of photo/electrocatalysts are then comprehensively introduced, with a thorough discussion of their respective advantages and limitations. Moreover, the data analysis via machine learning techniques, which not only accelerates the identification and refinement of potential new catalysts but also offers insights for enhancing the high‐throughput synthesis of catalysts, is introduced in detail. Then the representative examples are presented to illustrate the applications of large‐scale catalysts in the field of industrial‐level photo/electrocatalysis. Finally, the challenges and prospects in the development of large‐scale production of photo/electrocatalysts are discussed. By bridging the gap between laboratory research and industrial application, this review aims to provide a reference for the future of large‐scale preparation of photo/electrocatalysts in sustainable energy conversion and beyond. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Side‐chain engineering has emerged as a highly effective strategy for tailoring the aggregation behavior and charge transport properties of non‐fullerene small molecule acceptors (SMAs). In this study, we designed and synthesized two SMAs, namely BTPSi‐Bu and BTPSi‐Pr, respectively incorporating tributylsilyloxy and triisopropylsilyloxy groups in their outer positions. Notably, BTPSi‐Bu exhibited better planarity, crystallization, and favorable phase separation when paired with PM6 donor polymer compared to its counterpart, BTPSi‐Pr. The resulting organic solar cells, utilizing the PM6:BTPSi‐Bu blend, demonstrated a remarkable power conversion efficiency of 17.41% and a high open‐circuit voltage of 0.859 V. These findings underscore the significance of integrating trialkylsilyloxy side chains into SMAs as a rational design approach for enhancing the performance of photovoltaic systems. [ABSTRACT FROM AUTHOR]

Theoretical computations have predicted that a reduction in binding energy between CoOOH and carbon structure when FeOOH interface is present. This interface replaces the formation of Co(OH) 2 nanosheets on carbon structures. The formation of high-quality Fe 0.35 Co 0.65 OOH, which exhibits exceptional OER performance, can be attributed to the substantial enhancement of oxygen-containing species adsorption abilities, as calculated using density functional theory (DFT). [Display omitted] Transition metal-based oxyhydroxides (MOOH) have garnered significant attention as promising catalyst for the Oxygen Evolution Reaction (OER). However, the direct synthesis of MOOH poses challenges due to the instability of trivalent cobalt and nickel salts, attrivuted to their high oxidation states. In this study, theoretical computations predicted that Co(OH) 2 nanosheets are exclusively formed on carbon structures, owing to the stronger binding energy between CoOOH and CC compared to Co(OH) 2. Furthermore, the presence of FeOOH interface reduces the binding energy between CoOOH and carbon structure. Experiment evidence confirms that CoOOH can be directly synthesized through controlled epitaxial growth on an FeOOH interface using a hydrothermal method. Moreover, the in-situ doping of iron leads to the formation of high-quality Fe 0.35 Co 0.65 OOH with exceptional OER performance, displaying a low overpotential of 240 mV at 10 mA cm−2 and a small Tafel slope of 43 mV dec-1. Density functional theory (DFT) calculations uncover the substantial enhancement of oxygen-containing species adsorption abilities by Fe 0.35 Co 0.65 OOH, resulting in improved OER activity. This work presents a promising strategy for the efficient preparation of layered cobalt oxyhydroxides, enabling efficient energy conversion and storage. [ABSTRACT FROM AUTHOR]

The current study addresses the chemical coprecipitation approach for synthesizing ZnFe 2 O 4 nanoparticles. Zeta potential analyses were employed to investigate the distribution of particle sizes, polydispersity, and stability within these systems. Rietveld refinement patterns unveiled the effective synthesis of the cubic-structured ZnFe 2 O 4 , devoid of any secondary phases. The outcomes showed the significant impact of the modification approach applied on the colloidal stability of the investigated nanoparticles. UV–Vis spectroscopy confirms that the band gap decreases, and absorption increases with doping. The photoluminescence spectroscopy of the samples revealed empty oxygen spaces and cracks in the structure had formed in the lattice. For electrocatalysis, 10 % Ce doped ZnFe 2 O 4 had an oxygen evolution reaction onset potential of 151 mV vs Ag/AgCl to obtain 10 mA/cm2 current density and the lowest Tafel slope of 35 mV/dec. Therefore, the strategic nanostructuring and design of nanomaterials incorporating earth metal-doped metal oxides are necessary to achieve superior electrochemical performance in their respective energy conversion applications. [ABSTRACT FROM AUTHOR]

In the energy harvesting field, it is critical to efficiently convert ambient vibrations into usable electrical energy, especially under conditions characterized by low amplitude and random excitations. This study introduces a novel hybrid bistable piezoelectric energy harvester (HBPEH) designed to optimize energy conversion in challenging environmental conditions. The HBPEH features a unique piezoelectric cantilever beam integrated with a dynamic amplifier at the fixed end, significantly enhancing both rotational and lateral displacements of the beam. This innovation lowers the threshold for snap-through events, crucial for maximizing energy transfer in bistable systems, and enables superior energy harvesting capabilities. Furthermore, the HBPEH demonstrates significantly higher power outputs when subjected to excitation intensities beyond critical levels, outperforming conventional energy harvesters. Extensive numerical and theoretical analyses confirm that the HBPEH offers a promising solution for applications hindered by suboptimal energy conversion rates. Its ability to operate effectively under diverse and unpredictable excitation conditions underscores the HBPEH's robustness and superiority in advanced energy harvesting scenarios. The design improvements introduced in this study highlight the potential of the HBPEH to transform energy harvesting approaches. By addressing the limitations of traditional harvesters, the HBPEH provides enhanced efficiency and reliability, making it suitable for a broader range of practical applications in variable environmental conditions. [ABSTRACT FROM AUTHOR]

2-dimensional (2D) piezoelectric materials have gained significant attention due to their potential applications in flexible energy harvesting and storage devices. Recently, niobium oxide dihalides NbOI2 stands out as a multifunctional anisotropic semiconductor family with an exceptionally high lateral piezoelectric constant (~21.8 pm/V), making it a promising candidate for energy conversion applications. Here we report the experimental observation of anisotropic in-plane piezoelectricity in multilayer NbOI2. Current-voltage relationships reveal a significant piezotronic effect in two typical crystalline orientations. Additionally, cyclic tensile and release experiments demonstrate an intrinsic current output of up to 140 pA when subjected to a tensile strain of 0.51%. A flexible piezoelectric nanogenerator prototype is demonstrated on the human finger and wrist, which opens up new avenues for the development of wearable electronic devices and provides valuable insights for further exploration in this field. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Side‐chain engineering has emerged as a highly effective strategy for tailoring the aggregation behavior and charge transport properties of non‐fullerene small molecule acceptors (SMAs). In this study, we designed and synthesized two SMAs, namely BTPSi‐Bu and BTPSi‐Pr, respectively incorporating tributylsilyloxy and triisopropylsilyloxy groups in their outer positions. Notably, BTPSi‐Bu exhibited better planarity, crystallization, and favorable phase separation when paired with PM6 donor polymer compared to its counterpart, BTPSi‐Pr. The resulting organic solar cells, utilizing the PM6:BTPSi‐Bu blend, demonstrated a remarkable power conversion efficiency of 17.41% and a high open‐circuit voltage of 0.859 V. These findings underscore the significance of integrating trialkylsilyloxy side chains into SMAs as a rational design approach for enhancing the performance of photovoltaic systems. [ABSTRACT FROM AUTHOR]

Developing highly efficient catalysts for oxygen evolution reactions using abundant earth-rich and non-precious metals poses a critical and indispensable challenge. In this study, Fe: 1, 3, and 5% and Cr: 2% doped ZnO nanoparticles (NPs) were synthesized by employing a simple solution combustion method (SCM) for oxygen evaluation reaction (OER). Using a variety of methods, the synthesized transition metal-doped metal oxides were thoroughly examined. The electrochemical behavior of the Fe and Cr-doped ZnO electrodes in an alkaline solution was investigated through LSV, EIS, CV, and CA. The electrochemical studies showed that ZnO/Cr/Fe:5 (η = 305 mV and Tafel slop = 46 mV/dec) demonstrates significant oxygen evolution reaction (OER) activity under alkaline conditions. All prepared samples exhibit good stabilities for up to 10 h. • Developing electrode materials with cost-effective for energy conversion. • Fe and Cr doped nanoparticles were synthesized by the solution combustion method. • ZnO/Cr/Fe:5 exhibited superior OER performance due to a reduced overpotential of 305 mV@10mAcm−2. • All electrocatalysts exhibited excellent long-term stability over 10 h. [ABSTRACT FROM AUTHOR]

The quest for heightened energy efficiency is inextricably linked to advancements in energy storage and conversion technologies, wherein multifunctional catalysts play a pivotal role by mitigating the slow kinetics endemic to many catalytic reactions. The intricate synthesis and bespoke design of such catalysts, however, present notable challenges. Addressing this, the present study capitalizes on a novel dissolution manufacturing strategy to engineer self‐supporting, nanoporous multifunctional electrocatalysts, circumventing the prevalent issue of customizing catalytic functionalities upon demand. This innovative approach grants the flexibility to finely tune the incorporation of active species and metalloid binders, culminating in the creation of a self‐supporting nanoporous metal glass electrocatalyst doped with RuO2 (NPMG@RuO2) with outstanding performance in alkaline media. The catalyst showcases superior electrocatalytic activity, achieving low overpotentials of 41.50 mV for the Hydrogen Evolution Reaction and 226.0 mV for Oxygen Evolution Reaction alongside sustained stability over 620 hours.These achievements are attributed to the distinct nanoporous architecture that ensures a high density of catalytic sites and mechanical strength, bolstered by the synergistic interplay between RuO2 and Pt‐based metallic glass. The findings provide a versatile template for the development of nanoporous multifunctional catalysts, signifying a leap forward in the realm of energy conversion technologies. [ABSTRACT FROM AUTHOR]

Designing multifunctional materials that mimic the light‐dark decoupling of natural photosynthesis is a key challenge in the field of energy conversion. Herein, we introduce MnBr‐253, a precious metal‐free metal–organic framework (MOF) built on Al nodes, bipyridine linkers and MnBr(CO)3(bipyridine) complexes. Upon irradiation, MnBr‐253 colloids demonstrate an electron photocharging capacity of ~42 C ⋅ g−1MOF, with state‐of‐the‐art photocharging rate (1.28 C ⋅ s−1 ⋅ g−1MOF) and incident photon‐to‐electron conversion efficiency of ~9.4 % at 450 nm. Spectroscopic and computational studies support effective electron accumulation at the Mn complex while high porosity and Mn loading account for the notable electron storage performance. The charged MnBr‐253 powders were successfully applied for hydrogen evolution under dark conditions thus emulating the light‐decoupled reactivity of photosynthesis. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of BiVO4 limits its applications in solar-to-hydrogen energy conversion. In this work, the zeolitic imidazolate framework ZIF-67 as a cocatalyst was immobilized on a BiVO4 nanocone via a solution-based photo-deposition method for photoelectrochemical water oxidation. Under the assistance of the nano-tip effect induced by the BiVO4 tip, nanoflower-like ZIF-67 was selectively grown at the vertex of the BiVO4 nanocone. The constructed BiVO4/ZIF-67 composite photoelectrode yielded a photocurrent of 0.92 mA cm−2 at ∼1.23 VRHE, which is about 3.5-fold that of pure BiVO4. In addition, surface/bulk charge separation efficiencies (ηsurf and ηbulk) were elevated when compared to those of the BiVO4 photoelectrode. Photoelectrochemical impedance spectroscopy (PEIS) and intensity modulated photocurrent spectroscopy (IMPS) measurements were further investigated to reveal the critical role of the modification of ZIF-67 in suppressing charge recombination and improving the photoelectrochemical activity of BiVO4. This research presents a feasible way to design a BiVO4/MOF composite photoanode induced by the nano-tip effect for enhanced photoelectrochemical water splitting performance. [ABSTRACT FROM AUTHOR]

This study investigates the performance of dynamic capacitance regulation technology in electric vehicle piezoelectric shock absorbers for energy recovery under varying road conditions. By simulating a quarter-vehicle suspension system, this paper comprehensively analyzes the energy recovery efficiency of piezoelectric shock absorbers on gravel, speed bumps, and bumpy road conditions, comparing the performance differences between traditional fixed capacitance and dynamic capacitance. The results demonstrate that dynamic capacitance regulation technology can automatically adjust the capacitance value in response to instantaneous voltage changes, thereby enhancing energy recovery efficiency under various road conditions. This technology not only improves the energy conversion efficiency of piezoelectric shock absorbers but also strengthens the system's adaptability to different vibration frequencies and amplitudes. Further simulation evidence confirms that piezoelectric shock absorbers, under dynamic capacitance regulation, achieve better energy recovery performance across diverse road conditions, offering new insights into improving the energy efficiency and sustainability of electric vehicles. The novelty of this research lies in the first application of dynamic capacitance regulation technology to the energy recovery system of electric vehicle piezoelectric shock absorbers, providing a new theoretical foundation and technical reference for optimizing electric vehicle energy recovery systems. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have been extensively studied and applied as promising active materials in the field of energy storage and conversion. Recently, conductive π‐d conjugated coordination polymers (CCPs) have garnered significant attention due to their high conductivity, high porosity, tunable components, and adjustable pore sizes. These CCPs typically consist of transition metal ions and organic ligands, forming an in‐plane π‐d conjugated system. In this review, a concise summary of the design principles are provided, synthesis methods, and reaction mechanisms of CCPs as electrodes for energy storage systems, including metal‐ion batteries and supercapacitors. In addition, several novel energy storage applications are highlighted, such as metal‐air batteries and photo‐enhanced batteries. Finally, the challenges that need to be addressed is discussed urgently and offer perspectives on the further application of CCPs in more advanced energy storage and conversion systems. [ABSTRACT FROM AUTHOR]

Zinc‐based batteries are emerging as the most promising candidates for large‐scale energy storage devices due to their low cost, high safety, and long‐term storage. However, zinc‐based batteries encounter challenges stemming from undesirable side reactions and zinc dendrites on the anode, as well as dissolution on the cathode. Owing to their extremely small size, substantial surface functional groups, and adjustable structure, carbon dots (CDs) present considerable benefits in augmenting coulombic efficiency, expanding cycle life, and enhancing the rate functionality of zinc‐based batteries. Herein, this review delves into the surface modification and morphological regulation of batteries elements by CDs, CDs composites, and CDs derivatives. Moreover, it systematically encapsulates the application of CDs in zinc‐based batteries, underscoring the pivotal role of CDs in the advancement of electrode technology. Finally, the review highlights the impediments and proposes potential avenues for utilizing CDs in zinc‐based batteries. This review aims to facilitate the development of superior solutions and provide scientific insights into energy storage technologies. [ABSTRACT FROM AUTHOR]

Metal-organic framework (MOF) derived metal oxide nanostructures hold immense promise as electrodes for energy storage/conversion applications, notably in supercapacitors and urea oxidation. This study explores into optimizing such nanostructures, specifically focusing on a Zr/Ni ratio of 1:1, which has exhibited favorable electrochemical and catalytic performance. Employing thorough characterization methods, including PXRD analysis, we verified the successful synthesis of a ZrO 2 /NiO binary phase (i.e. Zr/Ni) nanostructure via the MOF-derived approach, showcasing its versatility as a catalyst across diverse energy conversion domains. The Zr/Ni nanostructure electrode displayed noteworthy characteristics, boasting a capacity of 432 C/g alongside exceptional cycling stability of 99%, reflecting battery-like electrochemical behavior. Furthermore, in an asymmetric device setup (Zr/Ni//AC), it achieved a notable potential of up to 1.4 V with an impressive power density of 1044.56 W/kg. Additionally, the Zr/Ni nanostructure demonstrated efficient electrocatalytic activity in urea oxidation, evidenced by a maximum current density of 60 mA/cm2. This underscores its viability as a preferred catalyst in energy conversion applications, signaling opportunities for further exploration and advancement in this dynamic field. [Display omitted] • Successful formation of a binary phase of Zr/Ni nanostructure achieved by single step route. • Zr/Ni nanostructure demonstrated a specific capacity of 432C/g. • Zr/Ni//AC device showed ED of 4.08 Wk/g@ 420 W/kg. • Zr/Ni nanostructure exhibits a low onset voltage (1.34 V) in urea oxidation. • Zr/Ni nanostructure shows the highest current density of 60 mA/cm2. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) have been widely used to harness various forms of mechanical energy for conversion to electrical energy. However, the contentious challenge in characterising TENGs is the lack of standard protocols for assessing mechanical‐to‐electrical energy conversion processes. Herein, macroscopic signal analysis is used to identify three key charging events within triboelectric signals: charge induction (CI), contact electrification (CE), and electrostatic discharge (ESD). By considering two phases of motion during contact‐separation (approach and departure of the contact materials), CI arising from the motion of bound surface charge (varying electric field) between opposing contact materials is shown to dominate the measured displacement current signal, rather than the process of CE itself. Furthermore, the conventional signal (i. e. voltage, current, charge) interpretation of CE and CI during approach and departure phases is re‐assessed, to indicate that the sudden spike of current often observed immediately prior to contact (or after separation) arises from polarity inverting electrostatic discharge (ESD). This aspect of the measured triboelectric effect, which is often ignored, is crucial for the design of TENGs and hence, techniques to enhance the understanding and control over the stochastic occurrence of ESDs is explored. The methods proposed for the deconvolution of the macroscopic signal components of TENGs, and mitigation of ESD occurrences, will allow for precise quantification of the associated charging events. The applications of this study will template the design and development of future super‐TENGs with optimised energy conversion capabilities. [ABSTRACT FROM AUTHOR]

Hetero-interface regulation for space charge transfer is an effective strategy to achieve high-performance hydrogen evolution reaction (HER) electrocatalysis. We have constructed heterostructured Co3Mo3N/Co particles confined in porous N-doped carbon (Co3Mo3N/Co@PNC) to decrease alkaline HER energy barrier, and the synergistic mechanisms of Co3Mo3N and metal Co were identified by experiments and theoretical calculations. The heterostructure induces charge transfer from Co to Co3Mo3N at the interface, which results in increased electron density on the Co3Mo3N part, enriched and enhanced active sites, and balanced adsorption-free energy of H2O dissociation and *H intermediates. As expected, Co3Mo3N/Co@PNC showed remarkable HER activity with a low HER overpotential of only 67 mV and the extremely lower Tafel slope of 43.1 mV dec−1, which can compete with the most of recently reported catalysts. What is more, the excellent stability of Co3Mo3N/Co@PNC over 20 h was superior to Pt/C, verifying great industrial prospects to replace nobel-metal-based catalysts for efficient energy conversion. [ABSTRACT FROM AUTHOR]

This work presents a novel approach to achieve directional and normal thermal emission from epsilon‐near–zero (ENZ) materials. ENZ materials exhibit near–zero permittivity at the ENZ point, resulting in some unique properties compared to conventional optical materials including infinite wavelength, constant phase distribution, and decoupling of spatial and temporal fields inside the ENZ material. These properties are used to engineer the far‐field thermal emission from optical antennas fabricated on ENZ film in the mid‐infrared. By coupling the antenna resonance mode with the Berreman mode of the ENZ material, highly directional and normal emission is demonstrated. This approach could have significant implications for thermal management, energy conversion, and sensing applications. [ABSTRACT FROM AUTHOR]

Creating an innovative and environmentally friendly energy storage system is of vital importance due to the growing number of environmental problems and the fast exhaustion of fossil fuels. Energy storage using porous carbon composites generated from biomass has attracted a lot of attention in the research community. This is primarily due to the environmentally friendly nature, abundant availability in nature, accessibility, affordability, and long‐term viability of macro/meso/microporous carbon sourced from a variety of biological materials. Extensive information on the design and the building of an energy storage device that uses supercapacitors was a part of this research. This study examines both porous carbon electrodes (ranging from 44 to 1050 F/g) and biomasses with a large surface area (between 215 and 3532 m2/g). Supposedly, these electrodes have a capacitive retention performance of about 99.7 percent after 1000 cycles. The energy density of symmetric supercapacitors is also considered, with values between 5.1 and 138.4 Wh/kg. In this review, we look at the basic structures of biomass and how they affect porous carbon synthesis. It also discusses the effects of different structured porous carbon materials on electrochemical performance and analyzes them. In recent developments, significant steps have been made across various fields including fuel cells, carbon capture, and the utilization of biomass‐derived carbonaceous nanoparticles. Notably, our study delves into the innovative energy conversion and storage potentials inherent in these materials. This comprehensive investigation seeks to lay the foundation for forthcoming energy storage research endeavors by delineating the current advancements and anticipating potential challenges in fabricating porous carbon composites sourced from biomass. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LSBs) are considered next‐generation energy storage and conversion solutions owing to their high theoretical specific capacity and the high abundance/low‐cost of sulfur‐based cathode materials. However, LSBs still encounter significant challenges, including the low conductivities of sulfur‐based materials, severe volumetric expansion of sulfur during the discharge process, and the persistent "shuttle effect" of polysulfides. In recent years, a tremendous amount of research has been conducted to address the above challenges by developing coating and compositing materials and corresponding fabrication strategies for sulfur‐based cathode materials. In this study, the surface coating, compositing materials, and fabrication methodologies of LSB cathodes are comprehensively reviewed in terms of advanced materials, structure/component characterization, functional mechanisms, and performance validation. Some technical challenges are analyzed in detail, and possible future research directions are proposed to overcome the challenges toward practical applications of lithium‐sulfur batteries. [ABSTRACT FROM AUTHOR]