High-performance Hybrid Research Articles

Interlayered Ti3C2TX/TiO2/ZnO nanoarchitecture for visible light-activated ultrasensitive triethylamine detection

Photoexcitation is an effective method to promote specific gas sensing performance of semiconductor for electronic device. In this work, an interlayered Ti3C2TX/TiO2/ZnO ternary nanoarchitecture was successfully prepared via sequential etching-intercalation and pyrolysis methods, for which the ZIF-8 nanoparticles were initially incorporated into the adjacent interlayers of laminated Ti3C2TX MXene derived from HF-etching of Ti3AlC2 MAX phase. The resultant multilayered Ti3C2TX/ZIF-8 nanocomposite was pyrolyzed at 400 oC to form Ti3C2TX/TiO2/ZnO ternary heterostructure, showing high triethylamine (TEA) sensing performance with Ra/Rg = 98 at 270 oC under 620 nm red-light irradiation, which is 3.1 times higher than that of the value measured under darkness. A rapid response/recovery time of 17 s/86 s is achieved, and it shows excellent TEA sensing selectivity and long-term cyclic stability. The close-stacked nano-/microstructure of Ti3C2TX/TiO2/ZnO effectively contribute to the diffusion and permeation of gas molecules, as well as the photogeneration and migration of charge carriers, leading to its outstanding photoactivated TEA sensing performance. This work provides a feasible approach to exploring high-performance Mxene hybrids for ultrasensitive TEA monitoring.

Hydrochloric acid induced microstructural reconfiguration from bulk α-NiS microspheres to porous/hollow NiSx microspheres for high-performance hybrid supercapacitor

Nickel sulfide is well known as a promising energy storage/conversion material considering its high redox activity, high theoretical capacity, easy preparation, and rich phase structures. Unfortunately, nickel sulfide prepared by conventional methods usually exhibits a bulk structure, which significantly limited its charge storage. To overcome this obstacle, we developed a facile hydrochloric acid-induced structure reconstruction strategy to fabricate porous and hollow structured nickel sulfide via a one-step hydrothermal process. We found that nickel sulfide undergoes de-nickelization in the presence of 3 M hydrochloric acid, resulting in the transformation from bulk structure to porous/hollow structures, accompanied by a transition from nickel-rich phase (α-NiS) to nickel-deficient phase (Ni3S4 or NiS2). The electrochemical results demonstrated the obviously improved specific capacity of nickel sulfide after structure reconstruction, among which the porous NS-HCl-1 h (α-NiS/Ni3S4) microspheres delivers the highest specific capacity (204.4 mAh g-1 at 1 A g-1) and show a rate performance about 50.0% from 1 to 20 A g-1. The assembled NS-HCl-1 h//rGO supercapacitor delivers a maximum energy density of 47.1 Wh kg-1 at a power density of 803.6 W kg-1, and maintain a capacity retention rate about 88.6% after 10,000 cycles. This work provides a novel method and contributes new insight for the structural reconstruction of transition metal sulfides (TMSs).

Biomass-Derived Carbon Materials for Advanced Metal-Ion Hybrid Supercapacitors: A Step Towards More Sustainable Energy

Modern research has made the search for high-performance, sustainable, and efficient energy storage technologies a main focus, especially in light of the growing environmental and energy-demanding issues. This review paper focuses on the pivotal role of biomass-derived carbon (BDC) materials in the development of high-performance metal-ion hybrid supercapacitors (MIHSCs), specifically targeting sodium (Na)-, potassium (K)-, aluminium (Al)-, and zinc (Zn)-ion-based systems. Due to their widespread availability, renewable nature, and exceptional physicochemical properties, BDC materials are ideal for supercapacitor electrodes, which perfectly balance environmental sustainability and technological advancement. This paper delves into the synthesis, functionalization, and structural engineering of advanced biomass-based carbon materials, highlighting the strategies to enhance their electrochemical performance. It elaborates on the unique characteristics of these carbons, such as high specific surface area, tuneable porosity, and heteroatom doping, which are pivotal in achieving superior capacitance, energy density, and cycling stability in Na-, K-, Al-, and Zn-ion hybrid supercapacitors. Furthermore, the compatibility of BDCs with metal-ion electrolytes and their role in facilitating ion transport and charge storage mechanisms are critically analysed. Novelty arises from a comprehensive comparison of these carbon materials across metal-ion systems, unveiling the synergistic effects of BDCs’ structural attributes on the performance of each supercapacitor type. This review also casts light on the current challenges, such as scalability, cost-effectiveness, and performance consistency, offering insightful perspectives for future research. This review underscores the transformative potential of BDC materials in MIHSCs and paves the way for next-generation energy storage technologies that are both high-performing and ecologically friendly. It calls for continued innovation and interdisciplinary collaboration to explore these sustainable materials, thereby contributing to advancing green energy technologies.

Chemical route synthesis of nanohybrid MoO3-rGO for high-performance hybrid supercapacitors

Asymmetric Hybrid supercapacitor (AHS) is distinguished by a combination of electrostatic and electrochemical storage mechanisms. High performance of AHS is based on MoO3 (MO) hybridized with reduced graphene oxide (rGO). In the present study, a single step hydrothermal method was used to synthesise MO and MoO3-rGO (MOG) nanohybrid materials. MO and MOG samples were then used to prepare electrodes. These electrodes were subjected to CV, GCD, and EIS analyses with three- and two-electrode systems. Results showed that the MOG-2 composite achieved a higher specific capacity of 607.82 C g−1 than bare MO at 96 C g−1 at a sweep rate of 2 mVs−1 in the three-electrode system. Thus, rGO can effectively enhance active sites for redox reactions. At current density of 1 A g−1, the MOG//rGO had the highest specific capacity of 188.40 C g−1. Based on GCD evaluation, the HSC coin cell device had a maximum energy density of 36.78 Whkg−1 and a power density 2546.84 Wkg−1and the device retained 87.6 % capacity after 10,000 cycles.

Interlaced-structural composite assembled by nickel cobalt layered double hydroxides and superfine coal for electrode material in high-performance hybrid supercapacitor

Nickel-cobalt hydrotalcite (NiCo-LDH) is widely acknowledged as a promising electrode material due to its high specific capacitance and energy density. However, in order to further enhance its cycle stability, the assistance of functional carbon materials is required. In this study, a superfine coal (FC) with an oxygen-enriched surface prepared through ball milling modification is incorporated into hydrothermal synthesis process of NiCo-LDH to form a composite known as NiCo-LDH/FC (NiCo-FC). When 0.325 g FC is added, the resulting NiCo-3FC exhibits an interlaced-structural characteristic along with excellent electrochemical properties and cycle stability. In a 6 M KOH electrolyte, NiCo-3FC demonstrates a significantly higher specific capacitance of 2101.03 F g−1 at a current density of 1 A g−1 compared to that of pristine NiCo-LDH (1706.44 F g−1). The hybrid supercapacitors (HSC) assembled using NiCo-3FC and popcorn carbon (PC) achieves a capacitance of 302.19 F g−1 at 1 A g−1 within the voltage range of 1.6 V, outperforming HSC assembled using NiCo-LDH and PC (257.58 F g−1), while exhibiting remarkable enhancement in cycle stability from 54.32 % to 83.63 % after undergoing 5000 cycles. Moreover, it displays a high energy density of 104.57 Wh kg−1 at a low power density of 0.79 kW kg−1, indicating that NiCo-3FC deserves recognition as a high-performance electrode material with significant practical value.

Nanoconfinement Effect in Water Processable Discrete Molecular Complex-Based Hybrid Piezo- and Thermo-Electric Nanogenerator.

Water-processable hybrid piezo- and thermo-electric materials have an increasing range of applications. We use the nanoconfinement effect of ferroelectric discrete molecular complex [Cu(l-phe)(bpy)(H2O)]PF6·H2O (1) in a nonpolar polymer 1D-nanofiber to envision the high-performance flexible hybrid piezo- and thermo-electric nanogenerator (TEG). The 1D-nanoconfined crystallization of 1 enhances piezoelectric throughput with a high degree of mechano-sensitivity, i.e., 710 mV/N up to 3 N of applied force with 10,000 cycles of unaffected mechanical endurance. Thermoelectric properties analysis shows a noticeable improvement in Seebeck coefficient (∼4 fold) and power factor (∼6 fold) as compared to its film counterpart, which is attributed to the enhanced density of states near the Fermi edges as evidenced by ultraviolet photoelectric spectroscopy and density functional based theoretical calculations. We report an aqueous processable hybrid TEG that provides an impressive magnitude of Seebeck coefficient (∼793 μV/K) and power factor (∼35 mWm-1K-2) in comparison to a similar class of materials.

High-performance hybrid glass fibre epoxy composites reinforced with amine functionalised graphene oxide for structural applications

Glass fibre-reinforced epoxy (GFRE) composites have had limited use as structural components in industrial applications (e.g., oil and gas, aerospace and civil infrastructure). The use of nanomaterials, such as graphene, has been explored recently to enhance the mechanical and long-term properties of GFRE to realise their full potential and increase their usage. This study evaluated the tensile, creep, and fatigue behaviour of amine-functionalised graphene oxide (fGO) modified glass fibre/epoxy laminate composites. A spray coating technique was used to coat the fGO particles onto the glass fibre surface, and epoxy composite laminates were manufactured using the vacuum resin infusion method. Creep and fatigue testing was performed under a load-controlled mode in tension. Adding fGO within the composites significantly improves the static, creep, and fatigue properties of the fGO-GFRE composites at both room and elevated temperatures. It is shown that fGO acts as a barrier to microcrack initiation and restrains the macrocrack propagation during cyclic loading under elevated temperatures in the GFRE composites. These factors, therefore, prevent the early delamination of the matrix and fibre interface during cyclic loading, which explains the fatigue life extension observed in the fGO-modified composites. With 0.05 wt% fGO, the fatigue life of the fGO-GFRE composites was extended by 8× and 30× at a maximum stress of 124 and 151 MPa respectively, in a 90 °C environment compared to the control GFRE composites. While the creep life compared to the control increased by 63×, 103× and 159× with 0.25 wt%, 0.5 wt% and 1 wt% fGO, respectively. These enhancements are attributed to the large surface area, high stiffness, and functional groups present, which provide a stronger bond between the composite phases. These features help restrict the mobility of the polymer chain during the creeping load and act as barriers to fatigue crack propagation, enhancing the composite’s durability. The nanocomposites produced display attractive properties for many possible industrial applications where improved performance is needed while maintaining a minimum cost.

Cyclic compressive behavior of high-performance hybrid fiber reinforced recycled aggregate concrete: Degradation law and acoustic emission features

To tackle the issues of inadequate mechanical properties of recycled aggregate concrete and its limited application in load-bearing structural components, a high-performance hybrid fiber reinforced recycled aggregate concrete (HP-HFRAC) was developed in this study. Sixteen groups of HP-HFRAC specimens fabricated with varying replacement rates of recycled coarse aggregate and different fiber parameters were subjected to uniaxial compression, as well as acoustic emission (AE) tests, to investigate the cyclic behavior and uncover the underlying mechanisms. The findings demonstrated a strong correlation between the AE signals and the macroscopic phenomenon throughout the whole compression process. The AE amplitude distribution was found to be capable of identifying damage mechanisms, including matrix cracking (40–50 dB), fiber sliding (50–80 dB), and fiber pull-out (more than 80 dB). Additionally, the inclusion of hybrid fibers contributed to mitigating the degradation of stiffness and the accumulation of plastic strain, resulting in the ductile failure of the specimens and significantly enhancing the energy dissipation capacity. Specifically, the peak stress of specimens with 1.5% steel fibers increased by 19% compared to that of specimens without steel fibers, compensating for the strength loss due to the presence of recycled coarse aggregate. Finally, constitutive equations governing the skeleton curves and the unloading and reloading curves of HP-HFRAC subjected to cyclic compression were formulated, which were validated using both the test results and the predicted results of the physics-based data-driven model previously published in our companion paper. The findings of this study might contribute to the development of sustainable high performance recycled aggregate concrete for reliable application in load-bearing components.

Vacancy-Defect Ternary Topological Insulators Bi2Se2Te Encapsulated in Mesoporous Carbon Spheres for High Performance Sodium Ion Batteries and Hybrid Capacitors.

Ternary topological insulators have attracted worldwide attention because of their broad application prospects in fields such as magnetism, optics, electronics, and quantum computing. However, their potential and electrochemical mechanisms in sodium ion batteries (SIBs) and hybrid capacitors (SIHCs) have not been fully studied. Herein, a composite material comprising vacancy-defects ternary topological insulator Bi2Se2Te encapsulated in mesoporous carbon spheres (Bi2Se2Te@C) is designed. Bi2Se2Te with ample vacancy-defects has a wide interlayer spacing to enable frequent insertion/extraction of Na+ and boost reaction kinetics within the electrode. Meanwhile, the Bi2Se2Te@C with optimized yolk-shell structure can buffer the volume variation without breaking the outer protective carbon shell, ensuring structural stability and integrity. As expected, the Bi2Se2Te@C electrode delivers high reversible capacity and excellent rate capability in half SIB cells. Various electrochemical analyses and theoretical calculations manifest that Bi2Se2Te@C anode confirms the synergistic effect of ternary chalcogenide systems and suitable void space yolk-shell structure. Consequently, the full cells of SIB and SIHC coupled with Bi2Se2Te@C anode exhibit good performance and high energy/power density, indicating its widespread practical applications. This design is expected to offer a reliable strategy for further exploring advanced topological insulators in Na+-based storage systems.

Design, analysis, and manufacturing of a glass-plastic hybrid minimalist aspheric panoramic annular lens

We propose a high-performance glass-plastic hybrid minimalist aspheric panoramic annular lens (ASPAL) to solve several major limitations of the traditional panoramic annular lens (PAL), such as large size, high weight, and complex system. The field of view (FoV) of the ASPAL is 360° × (35° ∼ 110°) and the imaging quality is close to the diffraction limit. This large FoV ASPAL is composed of only 4 lenses. Moreover, we establish a physical structure model of PAL using the ray tracing method and study the influence of its physical parameters on compactness ratio. In addition, for the evaluation of local tolerances of annular surfaces, we propose a tolerance analysis method suitable for ASPAL. This analytical method can effectively analyze surface irregularities on annular surfaces and provide clear guidance on manufacturing tolerances for ASPAL. Benefiting from high-precision glass molding and injection molding aspheric lens manufacturing techniques, we finally manufactured 20 ASPALs in small batches. The weight of an ASPAL prototype is only 8.5 g. Our framework provides promising insights for the application of panoramic systems in space and weight-constrained environmental sensing scenarios such as intelligent security, micro-UAVs, and micro-robots.

Bimetal-organic frameworks derived redox-type composite materials for high-performance energy storage

Electrodes and electroactive materials are crucial components in the development of supercapacitors due to their geometric properties. In this study, bimetal-organic frameworks (Bi-MOFs, ZIF-8@ZIF-67) were utilized as electrode materials for a high-performance hybrid supercapacitor (HSC) by designing a novel synthesis of metallic carbonate hydroxide/oxides. In particular, the Bi-MOFs function as a sacrificial precursor in the synthesis of hollow NiMn(CO3)0.5·0·.11H2O/ZnO@Co3O4 CNCs (NM-CH/ZnO@Co3O4 CNCs) cubic composite materials by a straightforward low-temperature treatment. The NM-CH/ZnO@Co3O4 CNCs exhibited exceptional electrochemical performance with high specific capacity of 196.3 ± 0.08 mAh/g, specific capacitance of 1179 ± 0.10 F g−1 at 0.5 A g−1, and outstanding cycling stability of 98% after 25,000 cycles compared to the other electrode materials. The porous and hollow structure, along with a large surface area, contributed to the enhanced electrochemical properties of the composite material. An HSC was constructed using NM-CH/ZnO@Co3O4 CNCs as the cathode and activated porous carbon (APC) as the anode, resulting in a device with a specific energy of 33 ± 0.12 Wh kg−1 and a power density of 19354 ± 0.07 W kg−1. The use of Bi-MOF electrodes presents new avenues for the development of high-performance energy storage materials, with the potential for industrial energy storage application demonstrated though the successful powering of portable lightbulbs.

ZnMnCo-S nanoneedle arrays as battery-type eletrodes for high-performance hybrid supercapacitors

Transition metal sulfides are used in the field of supercapacitors due to their remarkable electrical conductivity and superior energy density. However, few research has been conducted on how the sulfidation process affects the structure and electrochemical properties of electrodes. The nanoneedle array Zn-Mn-Co sulfide (ZMC-S/NF) electrode is prepared by directly growing on nickel foam (NF) via a two-step hydrothermal technique. During the first step, the Zn-Mn-Co carbonate hydroxide nanoneedle skeleton can be obtained. During the second step, the nanoneedle skeletons are etched, and rough nanoneedle arrays are created by the introduced sulfur ions,i.e., the sulfidation process. The ZMC-S/NF electrode exhibits a specific capacity of 1401.0 C g−1 at 2 A g−1. It still has excellent rate performance with a specific capacity of 1015.3 C g−1 at 20 A g−1. Moreover, it exhibits excellent cycling stability with 81.9% capacity retention after 10,000 cycles. ZMC-S/NF as the cathode and activated carbon (AC) as the anode are assembled to be a hybrid supercapacitor (HSC), which has an energy density of 43.4 Wh kg−1 at a power density of 700.4 W kg−1. The effect of adding Zn and Mn to the Co3S4 on energy band structure and density of states during the sulfidation process is calculated by the DFT. The HSC devices constructed by two series-connected ZMC-S/NF//AC can light a star made by ten 1.8 V-red Light Emitting Diodes (LEDs) for 10 minutes.

Trade-off analysis between gm/ID and fT of GNR-FETs with single-gate and double-gate device structure

This study examines the operational parameters of field-effect transistors (FETs) using single-gate (SG) and double-gate (DG) graphene nanoribbons (GNRs) within the analog/RF domain. A detailed exploration is conducted through an atomistic pz orbital model, derived from the Hamiltonian of graphene nanoribbons, employing the nonequilibrium Green’s function formalism (NEGF) for analysis. The atomic characteristics of the GNRFETs channel are accurately described by utilizing a tight-binding Hamiltonian with an atomistic pz orbital basis set. The primary focus of the analysis revolves around essential analog/RF parameters such as transconductance, transconductance generation factor (TGF), output resistance, early voltage, intrinsic gain, gate capacitance, cut-off frequency, and transit time. Furthermore, the study assesses the gain frequency product (GFP), transfer frequency product (TFP), and gain transfer frequency product (GTFP) to evaluate the balance between transistor efficiency, gain, and cut-off frequency. The research outcomes indicate that double-gate GNRFETs exhibit superior analog/RF performance in comparison to their single-gate counterparts. However, both types of devices demonstrate cut-off frequencies in the gigahertz range. The extensive data presented in this study provides valuable insights into the characteristics of SG and DG GNRFETs, particularly in terms of the figure-of-merit (FoM) for analog/RF performance, offering a comprehensive analysis of the trade-offs in analog applications. In addition, the analysis has been extended be performing a high-performance hybrid 6T static random-access memory (SRAM) to get the impact in their circuit level variation as well as improvement in their circuit performance.

Ultrasonic-Assisted Electrodeposition of Mn-Doped NiCo2O4 for Enhanced Photodegradation of Methyl Red, Hydrogen Production, and Supercapacitor Applications

This paper presents a novel ultrasonic-assisted electrodeposition process of Mn-doped NiCo2O4 onto a commercial nickel foam in a neutral electroplating bath (pH = 7.0) under an ultrasonic power of 1.2 V and 100 W. Different sample properties were studied based on their crystallinity through X-ray diffraction (XRD), morphology was studied through scanning electron microscopy (SEM), and photodegradation was studied through ultraviolet–visible (UV–Vis) spectrophotometry. Based on the XRD results, the dominant crystallite phase obtained was shown to be a pure single NiCo2O4 phase. The optical properties of the photocatalytic film showed a range of energy band gaps between 1.72 and 1.73 eV from the absorption spectrum. The surface hydroxyl groups on the catalytic surface of the Mn-doped NiCo2O4 thin films showed significant improvements in removing methyl red via photodegradation, achieving 88% degradation in 60 min, which was approximately 1.6 times higher than that of pure NiCo2O4 thin films. The maximum hydrogen rate of the composite films under 100 mW/cm2 illumination was 38 μmol/cm2 with a +3.5 V external potential. The electrochemical performance test also showed a high capacity retention rate (96% after 5000 charge–discharge cycles), high capacity (260 Fg−1), and low intrinsic resistance (0.8 Ω). This work concludes that the Mn-doped NiCo2O4 hybrid with oxygen-poor conditions (oxygen vacancies) is a promising composite electrode candidate for methyl red removal, hydrogen evolution, and high-performance hybrid supercapacitor applications.

Cation-driven self-assembly of core–shell covalent organic frameworks@Ti3CN MXene nanospheres for high-performance aqueous zinc-ion hybrid supercapacitors

Rechargeable aqueous Zn-ion hybrid supercapacitors (ZISCs) with the superiorities of high theoretical capacity, low redox potential and aqueous electrolytes with superior ionic conductivity (∼1 S cm−1) are promising energy storage systems. However, a primary concern persists due to the absence of cathode materials with both high energy densities and satisfactory cycling stability for robust ZISCs. In this study, we design a spherical core–shell covalent organic frameworks@Ti3CN MXene (CM-P) cathode via a cation-driven electrostatic self-assembly strategy. The CM-P with the constructed heterostructures shows both well-organized pore channels and excellent intrinsic conductivity, facilitating fast accessibility to intrinsic redox-active sites (such as C = O and N), and promoting effective ion diffusion characterized by low energy barriers. Consequently, the CM-P cathodes demonstrate excellent electrochemical performance, featuring an ultrahigh specific capacity of 260 mAh/g at 0.1 A, a high-rate capability with 68 % retention at 1 A/g, and long-term cycling stability. First-principle calculations elucidate that the enhanced charge-storage mechanism relies on the heterostructures of CM-P, accelerating ion adsorption/diffusion and electron transfer. Furthermore, the assembled CM-P//Zn ZISCs devices show a high energy density of 217.1 Wh kg−1 along with power density of 22.3 kW kg−1. This work provides an innovative approach to design COFs-based heterostructures for advanced ZISCs.

High-Performance Zinc-Ion Hybrid Supercapacitor from Guilin Sanhua Liquor Lees-Derived Carbon Materials.

Aqueous zinc-ion hybrid supercapacitors (ZHSCs) have attracted considerable attention because they are inexpensive and safe. However, the inadequate energy densities, power densities, and cycling performance of current ZHSC energy-storage devices are impediments that need to be overcome to enable the further development and commercialization of this technology. To address these issues, in this study, we prepared carbon-based ZHSCs using a series of porous carbon materials derived from Sanhua liquor lees (SLPCs). Among them, the best performance was observed for SLPC-A13, which exhibited excellent properties and a high-surface-area structure (2667 m2 g-1) with abundant micropores. The Zn//SLPC-A13 device was assembled by using 2 mol L-1 ZnSO4, SLPC-A13, and Zn foil as the electrolyte, cathode, and anode, respectively. The Zn//SLPC-A13 device delivered an ultrahigh energy density of 137 Wh kg-1 at a power density of 462 W kg-1. Remarkably, Zn//SLPC-A13 retained 100% of its specific capacitance after 120,000 cycles of long-term charge/discharge testing, with 62% retained after 250,000 cycles. This outstanding performance is primarily attributed to the SLPC-A13 carbon material, which promotes the rapid adsorption and desorption of ions, and the charge-discharge process, which roughens the Zn anode in a manner that improves reversible Zn-ion plating/stripping efficiency. This study provides ideas for the preparation of ZHSC cathode materials.

Enhancement of zinc-ion storage capability by synergistic effects on dual-ion adsorption in hierarchical porous carbon for high-performance aqueous zinc-ion hybrid capacitors

Aqueous zinc-ion capacitors (AZICs) are considered potential energy storage devices thanks to their ultrahigh power density, high safety, and extended cycling life. Carbon-based materials widely used as cathodes in AZICs face challenges, such as inappropriate pore sizes, poor electrolyte–electrode wettability, and insufficient vacancy defects and active sites. These limitations hinder efficient energy storage capacity and long-term stability. To address these issues, the B and F co-doped hierarchical porous carbon cathode materials (BFPC) are constructed through a facile annealing treatment process. The BFPC-2//Zn device exhibited high capacities of 222.4 and 118.3 mAh g−1 at current densities of 0.2 and 10 A g−1, respectively. Notably, the BFPC-2//Zn device demonstrated long-term cycling stability with a high capacity retention of 96.9 % after 20,000 cycles at 10 A g−1. Additionally, the assembled BFPC-2 based AZICs displayed a maximum energy density of 175.8 Wh kg−1 and an ultrahigh power density of 17.3 kW kg−1. Mechanism studies revealed that the exceptional energy storage ability and charge-transfer process of the BFPC cathode are attributed to the synergistic effect of B and F heteroatoms and the coupling effect between vacancy defects and pore size. This work presents a novel design strategy by incorporating B and F active sites into hierarchical porous carbon materials, providing enhanced energy storage capabilities for practical application in AZICs.

Revealing the Indispensable Role of In Situ Electrochemically Reconstructed Mn(II)/Mn(III) in Improving the Performance of Lithium-Carbon Dioxide Batteries.

Li-CO2 batteries are regarded as promising high-energy-density energy conversion and storage devices, but their practicability is severely hindered by the sluggish CO2 reduction/evolution reaction (CORR/COER) kinetics. Due to the various crystal structures and unique electronic configuration, Mn-based cathode catalysts have shown considerable competition to facilitate CORR/COER. However, the specific active sites and regulation principle of Mn-based catalysts remain ambiguous and limited. Herein, this work designs novel Mn dual-active sites (MOC) supported on N-doped carbon nanofibers and conduct a comprehensive investigation into the underlying relationship between different Mn active sites and their electrochemical performance in Li-CO2 batteries. Impressively, this work finds that owing to the in situ generation and stable existence of Mn(III), MOC undergoes obvious electrochemical reconstruction during battery cycling. Moreover, a series of characterizations and theoretical calculations demonstrate that the different electronic configurations and coordination environments of Mn(II) and Mn(III) are conducive to promoting CORR and COER, respectively. Benefiting from such a modulating behavior, the Li-CO2 batteries deliver a high full discharge capacity of 10.31 mAh cm-2, and ultra-long cycle life (327 cycles/1308h). This fundamental understanding of MOC reconstruction and the electrocatalytic mechanisms provides a new perspective for designing high-performance multivalent Mn-integrated hybrid catalysts for Li-CO2 batteries.

Antifouling performance enhancement of PES membranes using hydrophilic nanoparticles of poly(dopamine-acrylate) for oil/water separation

Polydopamine-acrylate (P(A-D)x) nanoparticles were blended with polyethersulfone (PES) to fabricate a high-performance hybrid ultrafiltration (UF) membrane for the separation of water from oily wastewater. In tris-alkaline buffer solution at room temperature, P(A-D)x nanoparticles were synthesized by intramolecular Michael addition of dopamine with acrylic acid (AA) monomers. Hybrid PES membranes were prepared using P(A-D)x at 0.05–0.4 wt% and characterized using various assays including Field emission scanning electron microscopy (FESEM), Thermogravimetric analysis (TGA), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), and water contact angle (WCA). The membranes showed a significant increase in hydrophilicity, water permeability, and oil rejection (R). The primary and secondary pure water fluxes of the membrane with 0.2 wt% P(A-D)0.25 were 45% and 110.78% higher than those of neat PES membrane, respectively. For 3300 ppm oil feed solution, water flux during water/oil separation increased by 107%, while the oil rejection (R) remained at 99.08%. The surface of membrane was markedly hydrophilic, with a WCA about 40°, much lower than that of the neat PES membrane (80.67°). UF hybrid membranes also showed a remarkable reduction in oil adhesion on the membrane surface as well as superior antifouling performance for membranes containing 0.2 wt% P(A-D)0.25, flux recovery ratio (FRR) = 84.88 ± 3.27%, reversible fouling (Rr) = 51.12 ± 1.09%, and irreversible fouling (Rir) = 15.12 ± 3.27%. In addition, the pure water flux was 446% higher than that of the unmodified membrane after five cycles (900 minutes).

Comprehensive Analysis of Mechanical, Economic, and Environmental Characteristics of Hybrid PE/PP Fiber-Reinforced Engineered Geopolymer Composites

Engineered Geopolymer Composites (EGCs), known for their excellent tensile properties and lower carbon emissions, have gained widespread attention in the field of fiber-reinforced concrete. However, the high cost of high-performance synthetic fibers, a crucial component of EGCs, limits their practical engineering applications. In this study, by using low-cost PP fibers hybridized with PE fibers and adjusting the fly ash/ground granulated blast furnace slag (FA/GGBS) ratio, cost-effective, high-performing hybrid PE/PP-reinforced engineered geopolymer composites (H-EGCs) were developed. This study conducted axial compressive and tensile tests on H-EGCs with different FA/GGBS ratios (7:3, 6:4, and 5:5) and PP fiber replacement ratios (0%, 25%, 50%, 75%, and 100%), investigated the influence of FA/GGBS and PP fiber replacement ratio on static mechanical behavior, and evaluated the economic and environmental benefits based on mechanical performance indicators. The result indicated that the compressive strength of H-EGCs can reach 120 MPa when the FA/GGBS ratio is 5:5; however, an increase in FA/GGBS and PP fiber replacement ratio leads to a loss in compressive strength and elastic modulus. The incorporation of PP fibers in moderate amounts enhances ultimate tensile strain by reducing crack control ability, and the maximum tensile deformation capacity (7.82–9.66%) was obtained for H-EGCs with a PP fiber replacement ratio of 50%. The optimal economic and environmental benefits of H-EGCs are observed when the FA/GGBS ratio is 5:5 and the PP fiber replacement ratio is set at 50%.