In this study, a novel hybrid solar-nuclear power generation and hydrogen production system (SNPH) is proposed, which consists of a tower-type concentrating solar thermal collector system, a nuclear reactor, a supercritical CO2 Brayton cycle, and an alkaline electrolyzer for hydrogen production. This system adopts a parallel heat-source configuration. The overall system is modeled and debugged for optimization using MATLAB. The results show that, under the same boundary condition constraints, the parallel layout of heat sources used in this system outperforms the conventional tandem layout of heat sources, and has a maximum power generation of 148.7 MW at a split ratio of 0.63, corresponding to a thermoelectric efficiency of 40.74%. Then, the thermal energy distribution between the nuclear heat exchanger and molten-salt heat exchanger is adjusted to quantify the corresponding variations in net power output, hydrogen production power, and thermoelectric conversion efficiency, and the maximum hydrogen production rate and power generation were 711.2 kg/h and 161.4 MW, respectively. Next, the system's economic viability was analyzed, and the results showed that the optimal LCOE and LCOH were 0.15$/kWh and 6.315$/kg, respectively. Finally, exergy analysis was conducted on the system, and it was found that the sodium-cooled fast reactor exhibits the largest exergy destruction, followed by the tower-type concentrated solar thermal field, and the exergy efficiency of the condenser was the lowest. This study offers a new paradigm for the design of multi-heat-source multi-energy complementary systems.
High-torque-density and high-power-density motors are critical components of high-power podded marine propulsion systems, and efficient cooling is essential for limiting temperature rise while reducing motor volume and weight. This paper presents a conceptual thermal design for a 3 MW podded marine propulsion motor incorporating heat pipes. A composite cooling configuration, including a water–heat pipe–air system and a water–heat pipe–oil system, was proposed based on the operating requirements of high-power podded thrusters. An experimental apparatus was established to evaluate the performance of rotating heat pipes, and the effects of rotational speed and evaporator-section temperature on heat transfer rate, equivalent thermal conductivity, and Nusselt number were investigated. The results show that the rotating heat pipe exhibits improved heat transfer performance at higher rotational speeds and evaporator-section temperatures. Based on the experimental results, thermal simulations were conducted for the 3 MW podded marine propulsion motor with heat-pipe cooling. Under rated operating conditions, the application of stator heat pipes and rotating rotor heat pipes reduces the maximum temperature of the stator winding by 29.9 K and that of the rotor permanent magnet by 18.4 K. These results confirm the effectiveness of the proposed heat-pipe-based cooling approach for both stator and rotor thermal management. The proposed compact cooling design provides a feasible solution for improving the thermal performance, torque density, stability, and reliability of high-power podded marine propulsion motors, and also offers guidance for the thermal management of other high-power-density electrical machines.
With the theoretical energy density of up to 2600 Wh kg−1, lithium-sulfur batteries are regarded as a highly attractive candidate for next-generation energy storage technologies. In recent years, the influence of environmental conditions on their performance has emerged as a key research focus. This work systematically explores the mechanisms through which environmental variables affect the performance of lithium-sulfur batteries. The article begins with a concise overview of the battery's operating principles, the origin of the shuttle effect, and the associated kinetic challenges. Building on fundamental electrochemistry and practical device design considerations, a detailed analysis is then provided of how these environmental factors impact the sulfur cathode, the lithium anode, and the overall cell. Finally, the review highlights current challenges and emerging opportunities in managing the operational environment of lithium-sulfur batteries, with the aim of guiding future research and inspiring innovative approaches.
Lithium–sulfur batteries are compelling candidates for next generation energy storage, but the practical use of lithium sulfide (Li2S) cathodes is hindered by the exceptionally high voltage required for initial activation. Here, we demonstrate a proton-mediated electronic-structure engineering strategy to lower the activation barrier. By inducing a controllable solid-state proton-exchange reaction between Li2S and ammonium bifluoride (NH4HF2), protons interact with Li2S at localized interfacial regions without compromising its structural integrity. Spectroscopic measurements, in situ electrochemical analysis and ab initio molecular dynamics reveal that proton incorporation redistributes electron density around sulfur, weakens Li-S interactions and lowers the activation barrier for delithiation, reducing the initial activation voltage to 2.38 V vs. Li/Li+. Proton exchange also alters subsequent sulfur-conversion chemistry by decreasing the population of soluble polysulfide intermediates, thereby suppressing shuttle-related side reactions despite a modest kinetic penalty in later cycles. These findings establish controlled, localized proton exchange as an effective strategy for activating Li2S cathodes and offer a general framework for regulating metal-sulfide electrode reactions in high-energy electrochemical storage systems.
Zinc-ion hybrid capacitors (ZIHCs) offer safety, high capacity, and low cost. Hierarchical porous carbon cathodes featuring a long-range conductive network are critical for enhancing ZIHC performance. Carbon nanocoils (CNCs) possess a unique long-range helical periodicity and an amorphous-polycrystalline composite structure. The sp3-hybridized carbon defects within CNCs are susceptible to oxidation, which facilitates pore formation and extension, making them promising candidate materials for ZIHC electrodes. In this study, a dual-oxidation strategy of integrating ethanol-induced internal weak oxidation with external strong oxidation in air was employed to fabricate oxygen-doped hierarchically porous carbon nanocoils (EOCNC). The formed pore sizes of EOCNC are primarily distributed across three ranges: 0.4-0.6 nm, 0.6-1.2 nm, and 1.2-2.4 nm. The coexistence of pores in the ranges of 0.6-1.2 nm and 1.2-2.4 nm contributes to reducing the zinc ion diffusion barrier through stepwise desolvation, while the 0.4-0.6 nm ultramicropores hold potential to achieve further desolvation, thereby enhancing the overall capacity. The EOCNC cathode delivers a specific capacity of 147.8 mAh g-1, along with an exceptional rate capability (71.1% capacity retention at 20 A g-1). This study proposes a novel dual internal and external oxidation strategy to fabricate hierarchical porous carbon materials, providing a new pathway for the development of high-performance ZIHC cathodes.
Organic solar cells (OSCs) achieve high photovoltaic output largely by regulating the nanoscale morphological structure of their photoactive layers. Trace doping has emerged as a promising strategy to simultaneously optimize morphological characteristics and charge dynamics; however, conventional p-or n-type dopants are often constrained by limited molecular diversity, complex screening processes, and the risk of inducing undesirable recombination pathways. Herein, we report a multifunctional trace dopant, a benzotriazole derivative (1-HB), featuring a molecular skeleton that is highly compatible with the acceptor material L8-BO. At an ultralow concentration (0.05 mg mL-1), 1-HB enables precise morphology regulation in PM6:L8-BO film. Comprehensive characterization reveals that 1-HB synergistically modulates crystallization dynamic behavior of both donor (PM6) and acceptor (L8-BO) phases via strong intermolecular interactions, leading to enhanced molecular packing, increased structural order, improved crystallinity and coherence length, and the construction of an optimal vertical phase separation gradient that facilitates efficient charge transport. Femtosecond transient absorption spectroscopy further demonstrates that 1-HB accelerates charge separation, reducing the hole transfer lifetime tau 1 from 2.047 ps to 0.858 ps, while simultaneously optimizing charge separation pathways by decreasing the contribution of slower processes from 26.4% to 19.5%. These combined effects facilitate ultrafast exciton dissociation and suppress bimolecular as well as trap-mediated recombination, which in turn effectively reduces non-radiative energy losses. Consequently, the optimized devices deliver a best power conversion efficiency (PCE)-19.98%, a remarkable improvement over the 18.41% of control devices, along with simultaneous enhancements in fill factor (FF), open-circuit voltage (VOC) and short-circuit current density (JSC). This acceptor-skeleton-matched trace doping strategy establishes a general molecular design paradigm for high-efficiency, low-dosage active layer dopants, offering substantial promise for advancing high-performance organic photovoltaics.
Four distributions of characteristic timescales have been proposed for the analysis of electrochemical impedance spectroscopy (EIS) data. This review provides a unified treatment of all four distributions, covering their theoretical foundations, main properties, and practical applications. The assumptions and limitations of each distribution are also discussed to clarify its range of applicability. We then describe and compare the main deconvolution methods used to recover the four distributions from experimental data, and we outline a workflow for the analysis of impedance spectra that includes the synergistic use of more than one distribution. Several directions for future research are also identified. The review is conceived to clarify the practical role of these distributions in EIS analysis and to guide their use.
Viologen-based materials are widely used in electrochromic (EC) systems because of their reversible redox properties. However, their large energy gap makes it difficult to achieve efficient photochromism (PC) at the molecular level. This limitation restricts their further development into multifunctional responsive materials. Therefore, improving their photoresponses and integrating multiple stimuli into one system remain important challenges. Here, we report multi-stimuli-responsive composite hydrogels prepared by integrating viologen derivatives and TiO 2 nanoparticles (NPs) into a poly(vinylpyrrolidone) (PVP) polymer network. Under UV irradiation, the viologen composite hydrogels exhibit obvious photochromic behavior, showing a distinct purple coloration. The colored state can be maintained for more than one month under an N 2 atmosphere. Interestingly, the incorporation of TiO 2 enables thermochromic (TC) behavior in the viologen-based composite hydrogels. After heating at 80 degrees C for 10 min, a distinct blue coloration was observed. This work provides a practical strategy for the design of multifunctional chromic materials.
Manganese shows promise as an anode material in next-generation rechargeable batteries, owing to its greater theoretical capacity and more negative redox potential (-1.19 V vs. SHE) compared to zinc. However, practical application is hindered by severe corrosion, parasitic hydrogen evolution, and uncontrolled dendrite formation, which together compromise Coulombic efficiency and cycling durability. This review critically evaluates recent progress in electrolyte design strategies aimed at overcoming these obstacles, including highly concentrated aqueous systems, halogen-mediated non-aqueous electrolytes, and additive-driven interface modification. These approaches collectively extend the electrochemical stability window, suppress water-induced side reactions, and promote reversible Manganese plating/stripping. Additionally, alternative methods such as constructing artificial protective interlayers and tuning electronic structures via alloying are discussed, which effectively regulate nucleation behavior and reduce hydrogen evolution. By integrating these emerging insights, this review outlines key design principles and future directions for the development of practical Manganese-based battery anodes.
Autothermal methanol reforming addresses the external heating limitation from conventional methanol steam reforming process by integrating exothermic combustion with endothermic reforming. It enables the self-sustained operation and quick startup. However, the system still needs a high level of heat load with the unsatisfied efficiency. Herein, a coupled thermodynamic and exergy analysis of self-sustaining methanol reforming system is reported by integrating the membrane separation and waste heat recovery unit. The system achieves high thermal efficiency of 69.46% and an exergy efficiency of 64.62%. The implementation of waste heat recovery utilization significantly reduces the energy demand, elevating the overall energy and exergy efficiencies to 72.76% and 67.29%, respectively. The work provides a validated theoretical framework and practical design strategy for developing high-performance and self-sustained hydrogen production system.
The efficient and stable operation of solid oxide fuel cell (SOFC) stacks heavily depends on the spatial uniformity of the internal electrochemical and thermal fields. The gas distribution structure of an SOFC stack governs the flow and distribution of fuel and air within the stack, thereby influencing the temperature, species distribution, and overall power output of each individual cell. This study uses multi-physics coupled simulations to investigate the flow field, thermal gradient, species distribution, and power output of an SOFC stack under various gas distribution designs. To improve the flow uniformity of the conventional central gas distribution structure, this study proposes three approaches: opposite corner end gas distribution (OCD), expanded gas distribution chamber for direct distribution (ECD), and a diverging main gas channel design, which are systematically evaluated and compared. The computational results show that the OCD and ECD schemes improve the anode-side flow uniformity by 4.34% and 6.39%, respectively, while increasing the stack output power and slightly reducing the maximum temperature gradient. These findings validate the key role of adjusting the geometric configuration of the gas distribution chamber in performance enhancement. Furthermore, the diverging main gas channel design (with an optimal diverging angle of 20°) maintains a reasonable flow velocity at the inlet section and a relatively high static pressure in the mid-downstream region, thereby increasing the anode-side flow uniformity by 4.71%, significantly reducing the inlet flow difference among layers, and also slightly decreasing the maximum temperature gradient. The above results provide a strong design basis and technical support for the development of high-efficiency, long-life SOFC stacks.
Optimization of complex chemical processes under data-scarce conditions remains highly challenging due to strong nonlinearity, multivariable coupling, and hierarchical parameter interactions. Conventional surrogate-assisted optimization frameworks typically rely on static models and one-shot global search strategies, which often result in limited robustness, inefficient exploration, and sensitivity to initial sampling. To address these limitations, this study proposes a feature-guided closed-loop optimization framework, termed the Stepwise PSO-based Package for Optimization of Targeted process simulation (SPOT). The framework systematically integrates machine learning-based surrogate modeling, feature importance diagnostics, uncertainty-aware objective formulation, and staged optimization within an adaptive closed-loop structure. In particular, a stepwise PSO algorithm is developed to sequentially optimize dominant and secondary decision variables based on the identified feature hierarchy, thereby improving search efficiency and mitigating premature convergence. The framework iteratively updates surrogate models and optimization trajectories through data feedback, enabling data-efficient exploration of complex design spaces. Its effectiveness is demonstrated through a case study on membrane-assisted methanol synthesis via CO2 hydrogenation. Compared with conventional PSO, the proposed framework exhibits enhanced convergence stability, reduced sensitivity to initial conditions, and improved optimization performance, achieving simultaneous improvements in CO2 conversion and exergy efficiency. Owing to its process-agnostic and adaptive design, the SPOT framework provides a generalizable and data-efficient methodology for optimization of complex chemical and energy systems.
Reverse water-gas shift chemical looping (RWGS-CL) process is a highly attractive thermochemical CO2 utilization technology, yet oxygen carriers often suffer from insufficient low-temperature oxygen mobility and deactivation by high-temperature sintering. This study systematically examined the role of porous silica-based frameworks (ZSM-5, SBA-15, and SiO2 aerogel) in modulating the redox activity and stability of CoFe2O4 during RWGS-CL. The results showed that ZSM-5 with abundant microporous structure exhibited the most significant promotion of CoFe2O4 reducibility and oxygen vacancy formation, enhancing CO2-splitting activity. CoFe2O4 supported on 30 wt% ZSM-5 (CZ30) delivered the optimal performance, achieving CO yields of 13.8 and 11.4 mmol.g(CoFe)(-1) in the first and fifth cycles at 650 degrees C, respectively. However, Co segregation during redox cycling gradually reduced its activity. To overcome this limitation, an O-2-assisted strategy was introduced to ensure the complete re-oxidation of the CoFe alloy, facilitating the redox reversibility of the oxygen carriers. Under O-2-assisted conditions, the CZ30 catalyst maintained a CO yield of approximately 12.8 mmol.g(CoFe)(-1) over ten cycles, outperforming most reported supported iron-based and spinel oxygen carriers and demonstrating enhanced redox stability. These findings highlight that the textural characteristics of the support critically govern redox activity and stability of oxygen carrier, and further establish CoFe2O4/ZSM-5 as an effective material for CO2-splitting via RWGS-CL.
This study demonstrates the urgent need for sustainable solutions to reduce the environmental pollution caused by plastic waste and domestic wastewater discharge. To address this challenge, the microalga Spirulina has been shown as an effective resource for sustainable bioproduct production while simultaneously enabling the valorization of domestic wastewater (DWW). The algae was cultivated for a period of 16-days in DWW, restuls revealed that the biomass productivity increased steadily reaching a maximum of 0.83 g L-1 on day 12. Meanwhile, the methanol-water solvent combination supported for the highest phycocyanin extraction of about 22.5 mg L-1 from the Spirulina biomass. The residual algal biomass further utilized for the production of polyhydroxyalkanoates (PHAs) and biochar. Fourier transform infrared (FTIR) spectroscopy analysis of Spirulina-derived PHA revealed characteristic O-H and C-H stretching bands at 3270.1 and 2979.2 cm(-1), respectively. The band at 1626 cm(-1) attributed to C=O stretching, though partial purification. The presence of CHs bending at 1387 cm(-1) and strong ester C-O-C vibration in the 1241.6 cm(-1) region confirms the presence of polymer, indicating functional groups of PHA. The PHA-bioplastic film shows a uniform thickness of 0.12 +/- 1 mm, water absorption 16%, water solubility 33.27% and balanced chemical resistance, indicating the biodegradability of the material. In addition, torrefaction of the residual biomass produces biochar yield of 31%, demonstrating effective biomass valorization. Thermogravimetric analysis shows that the torrefied biochar contained lower volatile matter, higher fixed carbon content and improved thermal stability. This integrated approach shows the potential of DWW as an efficient medium for sustainable Spirulina cultivation, enabling pigment recovery and valorization of residual biomass into bioplastic and biochar.
High-performance oxygen reduction reaction (ORR) activity is an essential indicator of efficient electrocatalysts for rechargeable Zn-air batteries (ZABs). Metallenes have attracted considerable attention in energy and catalysis due to their unique properties. The modulation of metallenes through engineering the lattice strain, electronic structure, and crystallinity, etc., offers an opportunity but still challenging. In this study, we report a Pd metallene (Pdene) catalyst with abundant frustrated Lewis pairs (FLPs) on the exposed Pd facets, in which the introduced Cu and N atoms served as Lewis acid and base sites, respectively. The interfacial Lewis acid-base Cu center dot center dot center dot N pairs effectively decreased the intermediate adsorption, contributing to the improvement of catalytic activity and durability. As expected, the optimal Cu1/N-Pdene catalyst exhibits exceptional ORR performance with a half-wave potential of 0.93 V, surpassing the benchmark Pt/C. Moreover, theoretical calculations reveal the Cu center dot center dot center dot N FLP can optimize charge redistribution and d-band center of Pd, thus reducing the ORR barrier and accelerating ORR kinetics. With Cu1/N-Pdene as the air electrode, both aqueous and all-solid state ZABs deliver remarkable battery performance, with high open circuit voltage, power density, and excellent stability. This work not only highlights the crucial role of Lewis acid-base pairs in metallenes for ORR, but also provides a strategy to regulate the electronic structure of Pdene.
Perovskite solar cells (PSCs) offer high power conversion efficiency (PCE) and low-cost manufacturing, yet their commercialisation is hindered by the poor stability of large-area modules and the high cost of noble metal electrodes. Although printable carbon electrodes provide a low-cost and stable alternative, carbon-based perovskite solar modules have suffered from limited PCE. To address this, Wei et al. developed a scalable vapour-assisted surface treatment that overcomes the persistent trade-off between PCE and stability in fully printed carbon-based perovskite solar modules. This breakthrough resolves the critical PCE-stability-cost challenge, paving the way for industrial application of printed perovskite photovoltaics and supporting global low-carbon energy goals.
Benefiting from the intrinsically high safety, overall performance, and environmental compatibility in targeted applications, aqueous batteries have emerged as promising power sources for next-generation flexible and wearable electronics. However, their application potential remains largely constrained by insufficient electrochemical performance, inadequate mechanical compliance, and limited design freedom. 3D printing enables programmable, multi-material, and architecturally complex battery construction, offering a powerful route to address these limitations. Nevertheless, applying efficient 3D-printed aqueous batteries into flexible electronics requires a clear understanding on the interplays among the printing processes, materials, and structural design, as well as the end performance. In this review, a systematic framework is established to correlate 3D printing techniques with material selection, structural engineering, and integration of aqueous batteries in flexible electronics. First, representative 3D printing techniques are examined in terms of their key characteristics and applicability. The impacts of functional materials and components, including current collectors, electrolytes, and electrodes, together with 1D, 2D, and 3D structural designs enabled by 3D printing, on the electrochemical performance and mechanical adaptability are comprehensively discussed. Finally, integration strategies and representative applications of 3D printed aqueous batteries in flexible electronics are reviewed, and the remaining challenges and potential future directions are outlined.
Rational modulation of the Cu-ZnO interfaces by modifying Layered Double Hydrotalcite (LDH) with additives the provides a promising way for enhanced methanol production from CO2, while the extent to which the promoters contribute to the topological transformation process of LDH and the reaction pathway remains unexplored. Herein, a LDH-derived CuZnAl catalyst with manganese (Mn) promoter modification is designed for efficient CO2-to-methanol production. Compared with amorphous catalysts, at 260 degrees C and 5 MPa, the asoptimized CuZnAlMn-LDO exhibits a CO2 conversion of 23.03% with a STYMeOH of 584.15 gMeOH center dot kgcat Characterizations conform that the introduction of Mn content directly involves in the formation of LDH and boost the thermal stability of the LDH morphology, resulting in the reservation of LDH nanosheet structure with lower thickness and higher surface area after calcination. These modifications effectively trigger stronger electron transfer and boost the formation of Cu-ZnO interfaces for enhanced CO2 adsorption. Moreover, smaller and more dispersed Cu species were also observed on CuZnAlMn-LDO, effectively facilitating H2 dissociation. In-situ tests further demonstrate that the formation of formate and its further hydrogenation are accelerated. This work highlights that tuning the topological transformation of LDH structure could effectively regulate metal-support interaction to enrich Cu-ZnO interfaces for enhanced performances.
Green hydrogen is crucial for decarbonization, yet its production faces two major challenges: heavy reliance on scarce freshwater and declining photovoltaic efficiency with rising temperatures. To address these, Wang et al. proposed an integrated hybrid solar distillation–water electrolysis (HSD-WE) device (published in Energy & Environmental Science). It achieves hydrogen production from seawater and a high 12.6% solar-to-hydrogen efficiency via full-spectrum utilization. This work highlights these advances and discusses necessary optimizations in system architecture and scalability for future sustainable hydrogen systems.
