Energy technology最新文献

Potassium-ion batteries (KIBs) are a promising alternative to lithium-ion batteries due to their abundance and low cost. KTi₂(PO₄)₃ (KTP) is a NASICON-type material with high theoretical capacity (128 mAh g⁻¹) and low redox potential (1.6 V). However, it exhibits poor cycle stability and sluggish kinetics due to its low conductivity. Furthermore, selecting an appropriate electrolyte is a significant challenge in maintaining consistent electrochemical performance. To address this, KTi₂(PO₄)₃ nanoparticles were synthesized using a solid-state technique and coated with carbon KTi₂(PO₄)₃/C (KTP/C) derived from oleic acid. The conductive network improves ion transport and electrolyte infiltration. Structural and morphological investigations revealed an interconnected carbon framework. The performance of the KTP and KTP/C electrodes was evaluated using EC:DEC and EC:DMC electrolyte solvents. The initial discharge capacity of the KTP/C electrode was 80 and 90.9 mAh g⁻¹ at 20 mA g⁻¹. The synergistic effects of the electrolyte composition and carbon coating resulted in an electrode exhibiting reasonable capacity retention of up to 98%. The computational methods, such as bond valance site energy(BVSE) and charge distribution analysis (CHARDI) analysis, have revealed a minimal three-dimensional ion-migration barrier and have evaluated electrolyte stability and solvent compatibility. Overall, this study provides new insights for enhancing the strategic development of KTP/C anodes for high-performance K-ion applications.

Radiative cooling (RC) is a compelling passive thermal strategy, dissipating heat via thermal radiation to outer space (≈3 K) without energy input, being useful across subambient to above-ambient temperatures. Recent nanophotonics and metamaterials breakthroughs significantly enhance RC, enabling subambient cooling even under sunlight. This requires tailored spectral properties: high solar reflectivity (0.3–2.5 μm) to minimize heat gain, and high atmospheric window emissivity (8–13 μm) to maximize heat loss. However, widespread deployment faces hurdles in scalability, durability, cost, and adaptability. This review synthesizes recent progress in RC materials (polymers, photonic structures, paints), system designs, and applications like building thermal regulation, personal comfort textiles, and enhancing photovoltaic/electronic efficiency. It incorporates fundamental thermodynamics governing heat exchange, quantifying cooling power via relevant equations, and life-cycle sustainability considerations. Drawing from current literature, the review critically evaluates commercialization barriers, including the lack of performance standardization, long-term degradation, and manufacturability, and proposes research directions for robust, scalable, and viable RC technologies. Emphasis is placed on recent quantitative performance gains and the engineering challenges (atmospheric effects, parasitic heat gains, and material degradation) in translating lab-scale results to real-world deployments for a sustainable future.

The article presents a methodology for evaluating capital investments in new technologies for electricity production based on oxygen-fuel carbon dioxide power cycles. Methane is used as fuel in the base case of the calculation. The technique uses power-law dependences, which allow obtaining the result in the form of continuous cost functions of thermodynamic, mass-flow, power and other parameters. The calculated dependence can be obtained by considering the influence of any thermodynamic or energy factor. The methodology is presented in full and allows for a unit-by-unit evaluation of the power plant cost. Based on this evaluation, capital investments in four technologies based on the carbon dioxide power cycle were calculated. The Allam cycle, the Allam cycle with condensation (Allam-Z), and the cycles proposed by the authors are considered. Their detailed description is presented. Specific investment in technologies is 950–1400 $/kW, and for the Allam cycle, there is a minimum of specific investment in the zone of the turbine inlet temperatures of 1000–1100°C.

With the increasing global demand for clean energy, aqueous zinc-ion batteries have emerged as a promising candidate for large-scale energy storage owing to their high safety, low cost, and environmental friendliness. However, challenges associated with zinc metal anodes, such as dendrite formation, hydrogen evolution reactions, and corrosion, significantly hinder their cycling stability and commercial viability. This review systematically summarizes eight functional strategies involving artificial interfacial layers to address these issues. This review provides a systematic summary of eight functional strategies based on artificial interfacial layers designed to overcome these issues. By analyzing the mechanisms of various interfacial materials, it highlights their effectiveness in suppressing dendrite growth, mitigating side reactions, and enhancing cycling performance, and further offers perspectives and recommendations for the rational design of highly reversible zinc anodes.

In pursuit of developing a suitable sodium-ion conducting solid polymer electrolyte (SPE) with enhanced ionic conductivity at room temperature (RT), poly(vinylidene fluoride) (PVDF) is blended with poly(ethylene oxide) (PEO) of varying molecular weights and sodium nitrate (NaNO₃) at different loadings, via the solution blending technique. The impact of the molecular weight of PEO on the ionic conductivity, dielectric properties, and structural evolution of PVDF-50 wt% PEO blend incorporated with y wt% NaNO₃ (y = 0,1,3,5,7,9,10,12,15), is studied in detail. Fourier transform infrared (FTIR) spectroscopy analysis confirms PEO–Na⁺ interaction in SPEs, while X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analyses reveal suppressed PEO crystallinity, crucial for enhanced ion conduction. The highest ionic conductivity of 6.98 × 10⁻⁴ S cm⁻¹ at RT is achieved for PVDF-50 wt% PEO-9 wt% NaNO₃ with high molecular weight (HMW) PEO due to the availability of more coordinating sites. The mobility of mobile ions dominates the ionic conductivity in both HMW and low molecular weight (LMW) PEO-incorporated SPEs. The temperature-dependent conductivity studies reveal that both HMW and LMW PEO-incorporated SPEs follow Arrhenius behavior. The ion transference number, evaluated from the DC Wagner polarization method, is greater than or equal to 0.95 for selected SPEs.

The primary motivation for this work is to address the crucial need for effective energy storage technologies, given the importance of electrochemical energy as a clean, renewable, and efficient source. While conducting polymers, such as PPy, are promising for energy storage due to their ease of synthesis, high conductivity, processability, and environmental stability, their performance can be further enhanced by incorporating metal oxide nanoparticles. This study introduces the novel electrochemical deposition of PPy/NiZnFeO₄NPs nanocomposite films for supercapacitor applications, specifically leveraging the high electrical conductivity and catalytic activity of NiZnFeO₄NPs. Detailed characterizations, including chemical, crystal, morphological, and thermal properties, are conducted. Notably, the bandgap energy of pure PPy film (3.77 eV) decreases to 3.66 eV with NiZnFeO₄NPs incorporation, and electrical conductivity significantly increases from 32.5 to 101.8 mS cm⁻¹. The specific capacitance is enhanced from 43.64 F g⁻¹ for pure PPy to 192.80 F g⁻¹ for the nanocomposite at a scan rate of 25 mV s⁻¹ in KOH electrolyte, demonstrating superior performance for supercapacitor applications. This enhancement is attributed to the improved electrical conductivity and increased surface area provided by the NiZnFeO₄NPs. Additionally, it can be concluded that the $��K^{+}�$ diffusion-controlled intercalation reaction dominated the current in the electrochemical reactions.

A perovskite solar cell device is designed in which 2D perovskite with Dion–Jacobson (DJ) phase incorporated on prime photoactive 3D CsSnI_3−xBr_x with the cell configuration FTO/CeO₂/PeDAMA₄Pb₅I₁₆/CsSnI_3−xBr_x/CFTS/Au. The linear and parabolic grading of the absorber CsSnI_3−xBr_x along its depth in purposed device structure is performed by changing ‘Br’ composition (x) from 0 to 3. The impact of varying prime absorber thickness, composition of ‘Br’ (0–3), and bowing factor (0–1) on the linearly and parabolic-graded photovoltaic parameters are analyzed. The effect of series and shunt resistance, defect density of the CsSnI_3−xBr_x absorber, back contact metal work function, overall device operating temperature, and the variation of hole transport layers and electron transport layers are also extensively studied under both linear and parabolic grading conditions. The present detailed investigation and comprehensive analysis of the linearand parabolicgraded outcome revealed the superior photovoltaic performance with exceptionally impressive power conversion efficiency ≈36.96% at room temperature condition delivered by the purposed device along with excellent parameters V_oc ≈ 1.28 V, J_sc ≈ 35.83 mA cm⁻², and fill factor ≈80.40% for 1 μm thick CsSnI_3−xBr_x absorber at composition value x = 0 at CsSnI_3−xBr_x/HTL interface. The outcome of the present work categorically suggested the effect of introducing the DJ-2D perovskite on breaching the Shockley–Queisser limit.

Inspired by the palm leaf structure, this work developed a novel V-shape prism. The flow-induced vibration (FIV) mechanism of the V-shape prism under typical windward angles (α = 0°, 90°, and 180°) is studied by numerical simulation. The impact of wind speed and direction on vibration amplitude, frequency, force coefficient, phase, and vorticity contours is analyzed. The V-shape prism undergoes vortex-induced vibration (VIV) or galloping with the change of wind speed and direction. The vibration amplitude in galloping mode is higher than that in VIV mode. The wind speed and direction have little effect on the vibration frequency in galloping mode, while the vibration frequency in VIV mode is determined by the vortex shedding. The transform of the prism vibration mode is accompanied by a change of phase lag and vortex structure. The V-shape prism at α = 0° exhibits a significantly greater vibration amplitude and energy conversion efficiency compared to both the square prism and other windward angles. The highest energy conversion efficiency of the V-shape prism is 69.2%, which is 22.2 times that of the square prism device. This work presents the potential application of a V-shape prism in the future design of FIV energy harvesters.

The hybrid supercapattery combines the rapid charge–discharge capability of supercapacitors with the elevated energy storage capacity of batteries. In this study, PCN-777/WSe₂@g-C₃N₄ heterostructures are synthesized by a hydrothermal method and are evaluated for energy retention and hydrogen evolution reaction (HER) systems. PCN-777 provides a porous framework for ion transport and structural stability, while WSe₂ enhances electrical conductivity and mechanical strength. The g-C₃N₄ promotes interfacial coupling to improve pseudocapacitive storage. Scanning electron microscope and X-ray diffraction confirm uniform distribution and phase purity. Electrochemical analysis shows a specific capacity (Q_S) of 1700 C g⁻¹ at 2.0 A g⁻¹ in a three-electrode system. A hybrid device using PCN-777/WSe2@g–C3N4 as the anode and activated carbon as the cathode achieves 63.21 Wh kg⁻¹ at 800 W kg⁻¹ and retains 89.3% capacity after 1000 cycles. Kinetic analysis gives slope values of 0.60–0.79, confirming combined surface-controlled and diffusion-limited contributions. For HER, the composite requires an overpotential of 69.43 mV at 10 m A cm⁻² with a Tafel slope of 77.62 m V/dec, confirming efficient catalytic activity and electron transfer.