Materials Today Nano
·
2025
·
IF 8.2
Ziqi Zhang,Beibei Zhan,Yuhao Yang,Xiaosi Qi,Junfei Ding,Xiu Gong,Yunpeng Qu,Lei Wang
Metal organic frameworks are broadly used as promising precursors or templates for the fabrication of carbon-based derivatives owing to their exceptional porosities, structural diversities, and large specific surface areas. In this study, a facile method was reported to construct yolk-shell FeCo@air@C nanocomposites via annealing FeCo-prussian blue analogues (PBA)@phenolic resin (PR) precursor at different temperatures under Ar atmosphere. The introduction of PR effectively reinforced the stability of FeCo-PBA microstructure during carbonization process and played a confining role in preventing the serious agglomeration of FeCo nanoparticles. By adjusting the pyrolysis temperature, different categories of yolk-shell FeCo@air@C nanocomposites had been selectively established. Amongst, the FeCo@air@C obtained at 600 °C exhibited the superior electromagnetic wave absorption performances with a minimum reflection loss of -68.3 dB at the thickness of 2.44 mm and an ultrabroad effective absorption bandwidth of 8.2 GHz at 3.20 mm. Interestingly, its corresponding radar cross section value exhibited excellent radar stealth property in the practical applications. Therefore, the results elucidate that the combination of space confinement engineering and temperature optimization strategy is an indeed advanced method to regulate the electromagnetic wave absorption performances of magnetic carbon-based materials derived from FeCo-PBA.
✓ 已验证
产品关联
DOI
高影响因子
Energy Storage Materials
·
2024
·
IF 18.9
Mengzhao Yang,Huayan Liu,Chenxin Zhou,Haoyang Chen,Xin Chen,Qinglei Liu,Jiajun Gu
To realize ultrafast supercapacitors, a series of ultrahigh-rate (≥1000 mV s −1 ) anodes that break a well-known “energy vs. power dilemma” in aqueous electrolytes have been successfully developed over the past five years. However, their matching cathodes are still limited by slow ion transport dynamics and oxidation. Here, we report a series of hydrated films that comprise small sheets of reduced graphene oxide (SSs−rGO, <100 nm in average lateral size) and feature short interlayered pathways (∼100 nm) for rapid ion transport and high oxidation resistance. As the first ultrahigh-rate cathode with areal capacitance ( C a ) satisfying an industrial requirement (>0.6 F cm −2 ), the SSs−rGO electrode (5.0 mg cm −2 ) delivers a C a of 0.61 F cm −2 and a gravimetric capacitance of 123 F g −1 at an ultrahigh-rate of 3000 mV s −1 . Combining with a Ti 3 C 2 T x anode, the cathode enables a 1.8 V ultrafast aqueous supercapacitor that delivers energy densities of 0.14 and 0.09 mWh cm −2 for discharges in 1.79 and 0.97 s (∼2000 and 3700 C rate), respectively. These values double (at 2000 C) and almost ten-fold (at 3700 C) those of the ever-reported supercapacitors operating at the corresponding rates. The present strategy paves a road to ultrafast (>1000 C) and high-energy-density supercapacitors, by which energy charge/discharge can finish within 3.6 s.
✓ 已验证
产品关联
DOI
高影响因子
Lubricants
·
2024
·Vol. 12
·期 5
·176
·
IF 3.1
Junhao Han,Yong Tang,Luo Yue,Xianzhen Ma,Hao Jia,Ningxia Liu,Pengpeng Bai,Yonggang Meng,Yu Tian
Lubricants must exhibit good tribological behavior at low temperatures to ensure reliable startups in very cold regions. This study investigates the performance of lubricants, with a specific focus on their capacity for high-temperature lubrication and ensuring reliable low-temperature startup in engines. Experiments were conducted to assess the friction and wear characteristics of polydiethylsiloxane in conjunction with a Si3N4 ball and M50 (8Cr4Mo4V) steel across a temperature range of −80 °C to 25 °C. The results indicate that the coefficient of friction, as determined through friction and wear tests at various temperatures, remained below 0.1. As temperatures progressively decreased, the system’s friction coefficient increased, and wear volumes recorded at 25 °C and −60 °C were 9749.513 µm³ and 105.006 µm³, respectively, culminating in lubrication failure at −100 °C. This failure is primarily attributed to the increased viscosity and decreased mobility of polydiethylsiloxane at extremely low temperatures. Additionally, the reduced temperature increases the strength of the quenched steel, leading to hard particles or protrusions on the material’s surface, which collide with the Si3N4ball during friction, causing adhesion and spalling. Despite this, polydiethylsiloxane forms a stable protective oil film on the surface, enhancing the system’s lubrication performance. However, below −80 °C, this oil film begins to tear, leading to diminished lubrication efficacy. This study provides valuable data supporting the field of cryogenic lubrication.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Fengyu Gao,Jiyue Zhang,Jiaying Jiang,Xiaolong Tang,Yuansong Zhou,Honghong Yi
This paper explores an eco-friendly and efficient photocatalytic oxidation (PCO) technology aimed at converting NH 3 into N 2 , which holds considerable importance for environmental conservation and human well-being. Building upon previous investigations of N-TiO 2 catalysts, the research group successfully synthesized an N-TiO 2 catalyst featuring a carbon layer on its surface via mechanical mixing followed by calcination at 400 °C (denoted as C/N-TiO 2 (1), 1 represents the molar ratio of N and Ti). The analysis concentrated on the influence of C content on the PCO efficiency of NH 3 , revealing a peak performance correlated with increasing C levels. Notably, the C/N-TiO 2 (1) catalyst with 3.0 wt% C exhibited remarkable catalytic performance, achieving a conversion rate of 94 % and selectivity of 98 %. The enhancement of catalytic activity and selectivity is primarily attributed to the co-doping of C and N elements. Experimental results indicate that doping with N alone effectively suppresses the recombination of photogenerated carriers under visible light. Furthermore, the simultaneous doping of C and N significantly reduces the band gap energy of TiO 2 (3.18 to 2.90 eV), thereby broadening its photoresponse range. Concurrently, more Ov (Oxygen vacancy) are formed under visible light irradiation, which enhances the PCO performance. More importantly, more acidic sites are introduced to improve the catalyst’s adsorption capacity for NH 3 . Additionally, the impact of various reaction components on the PCO capability of the 3.0 wt% C/N-TiO 2 (1) catalyst is examined further. The findings indicate that oxygen anion radicals produced from O 2 play a critical role in facilitating NH 3 -PCO. However, the presence of CO 2 and extra H 2 O could hinder the approach of NH 3 molecules to the active sites and decrease the longevity of photogenerated ·OH, consequently reducing catalytic effectiveness. This research introduces fresh insights and optimization approaches for enhancing the activity, selectivity, and stability of catalysts.
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2025
·
IF 12.4
Cong Zhang,Zhipeng Zhang,Shuang Zhang,Yifeng Chen,Dunjie Li,Yongmei Li
Anaerobic co-digestion of sulfur-containing organic wastes with waste-activated sludge containing iron–phosphorus compounds (FePs) was recently suggested as an environment-friendly strategy to promote phosphate release, energy recovery, and hydrogen sulfide (H 2 S) control. Nevertheless, the mechanistic coupling between FePs speciation and the concurrent transformation of carbon, sulfur, iron, and phosphorus within this system remains to be fully elucidated. To address this knowledge gap, methionine, a typical hydrolysis product of sulfur-containing organics, and five FePs prevalent in sludge (ferric-phosphate tetrahydrate (FePO 4 ⋅4H 2 O), ferric-phosphate dihydrate (FePO 4 ⋅2H 2 O), vivianite (Fe 3 (PO 4 ) 2 ·8H 2 O), phosphate coprecipitated with Fe(III) (COP-P), and phosphate adsorption on hydrous ferric oxide (HFO-P)) were selected to elucidate C-S-Fe-P transformations in this study. The results showed that the H 2 S and methyl mercaptan productions decreased by >96% and >99%, respectively, while the methane production rate increased by 51.60–103.9% in the presence of FePs. The reaction between FePs and sulfide promoted the transformation of gaseous H 2 S and aqueous S 2− to solid sulfur species (elemental sulfur and iron sulfide precipitates), while simultaneously promoting the release of PO 4 3− from FePs. The formation of Fe(II) species derived from both abiotic sulfide-driven reduction and microbial-mediated iron reduction processes. The reduction rates of FePO 4 ⋅2H 2 O and FePO 4 ⋅4H 2 O were higher than those of COP-P and HFO-P, owing to their higher thermodynamic favorability. A negative correlation was observed between the Fe/P molar ratio and PO 4 3− release efficiency. FePO 4 (FePO 4 ⋅2H 2 O and FePO 4 ⋅4H 2 O) with the lowest Fe/P molar ratio achieved the highest P release efficiency (89.83–91.01%). Metagenomics analysis revealed that the SELENBP1 gene related to the degradation of methanethiol to sulfide was upregulated by 21.12–51.72% in the presence of FePs, and the genes involved in propionate metabolism, methylotrophic, and hydrogenotrophic methanogenesis were up-regulated concurrently. This study provides an in-depth understanding of C-S-Fe-P interactions and transformations during the anaerobic co-digestion of sulfur-containing organic wastes with FePs-containing sludge, helping to enhance methane production and the recovery of phosphorus and sulfur.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 27
·e04958
·
IF 2
Chen Minggui,Yan Liang
Graphical Nano-SiO₂ (0.02 wt%) extends gel stability to 95 days at 130 °C in seawater (versus 70 days control). SEM-confirmed H-bonding between Nano-SiO₂ silanols and AMPS groups reinforces network. Gelation activation energy (88.2 kJ/mol) derived via Arrhenius model. Nano-SiO₂-toughened polymer gels achieves 34.7 MPa/m breakthrough pressure (10 × base gel) in 1.4 Darcy cores. This study solves water shutoff gel syneresis/ degradation in high-salinity seawater (Ca 2 ⁺+Mg 2 ⁺ >1;500 mg/L) for South China Sea reservoirs. Reservoirs in the western South China Sea have entered a high-water-cut stage, exhibiting significant heterogeneity exacerbated by prolonged water flooding, necessitating urgent profile control measures to enhance oil recovery. Conventional polyacrylamide organic gels fail under the prevailing high-temperature (130 °C) and high-salinity conditions, characterized by divalent cation (Ca 2 ⁺ and Mg 2 ⁺) concentrations of 5650 mg/L. This study developed a robust gel profile control system specifically engineered for such challenging environments. Key parameters including polymer and crosslinker concentrations, gel pH, and temperature were systematically optimized to ensure stability under high temperature and salinity. The optimized formulation demonstrates exceptional stability in seawater at 130 °C, with a gelation activation energy of 88.2 kJ/mol. Incorporating nanosilica significantly enhanced the gel's thermal stability, salinity tolerance, and shear resistance. Scanning electron microscopy (SEM) revealed a strengthened network microstructure. The system exhibits favorable injectivity in 1.4 Darcy permeability cores. Nanosilica reinforcement dramatically increased the gel's breakthrough pressure gradient from 3.45 MPa/m to 34.7 MPa/m. Crucially, the addition of 0.02% nanosilica extended the polyacrylamide gel's functional stability from 70 days to 95 days. This nanosilica-reinforced system offers superior long-term stability and plugging performance, presenting a viable profile control and water-shutoff technology for offshore high-temperature, high-salinity seawater reservoirs.
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Yu Shi,Guanhua Ren,Jiajie He,Wei Yang,Jingjing Bao,Licheng Sun,Zhengyu Mo,Min Du
With the growing global demand for sustainable energy solutions, there is increasing interest in the conversion of low-grade heat into useful electrical energy. Thermoelectrochemical cells (TECs) are a promising technology for low-grade heat harvesting. However, sluggish reaction kinetics limit the power generation and efficiency of the TECs. In this study, we propose a Fe–N–C catalyst in situ grown on three-dimensional graphite felt as a self-supporting electrode for TECs. The graphite felt substrate provides a multidimensional structure to facilitate mass transport, while the Fe–N–C catalyst enhances electrode activity for redox reactions. The physicochemical properties and electrochemical performance of the electrode are characterized. The results demonstrate that the optimized electrode achieves a maximum power density of 1938 mW/m2 and a Carnot-relative efficiency of 2.29%, representing 11-fold and 12-fold improvements over graphite felt, respectively. These metrics surpass recent benchmarks in the field of TEC research. Furthermore, the electrode maintains a Carnot-relative efficiency of 2.0% in solar-driven TEC operation, demonstrating feasibility in photothermal and thermoelectrochemical conversion. Modeling analysis reveals that ion transport dominates heat and mass transfer processes, critically influencing power generation and stability, thereby highlighting the need for future optimization of ion transport pathways. This work validates the feasibility of in situ-grown Fe–N–C catalysts on graphite felt as high-performance TEC electrodes, offering a strategic framework for advancing waste heat recovery systems through rational electrode design and transport engineering.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Tianyang Xia,Qiang Gao,FuShuai Wang,Liancai Xun,Zibin Chen,Ping Hu
Carbon fiber reinforced ultra-high temperature ceramic matrix composites (C f /UHTCMCs) are considered ideal materials for thermal protection components in hypersonic vehicles due to their outstanding overall performance. However, the existing fabrication techniques for C f /UHTCMCs face significant engineering challenges, including high raw material costs and complex processing methods. Here we propose a cost-effective fabrication strategy. This approach ensures the oxidation and ablation resistance of the material by incorporating sufficient ZrB 2 and SiC, followed by filling the remaining pores in the composite with in-situ derived pyrolytic carbon from furfuryl ketone resin, which significantly reduces fabrication costs and enables rapid densification. The C f /ZrB 2 -SiC-C composites produced by this strategy exhibit a flexural strength of 468 ± 18 MPa and a fracture toughness of 18.23 ± 1.14 MPa m 1/2 . Furthermore, the composites remain non-ablative when exposed to temperatures of 2300 °C for extended periods, with a mass ablation rate of only 4.14 × 10 −6 g/(mm 2 ·s) after 400 s of testing. This strategy offers significant design versatility and can be applied to various ultra-high temperature ceramic systems, offering a novel and cost-effective approach to the development of thermal protection materials for hypersonic vehicles.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xinyue Mao,Qingnan Meng,Mu Yuan,Sifan Wang,Shiyin Huang,Yuting Qiu
Fe-based diamond -composites exhibit considerable potential for applications owing to their excellent mechanical and wear properties. However, the weak interfacial bonding between the Fe-based matrix and diamond particles has consistently limited their overall performance, adversely affecting the working efficiency of diamond tools. In this study, a Mo-B-C coating was pre-coated on the diamond surface. During the sintering process, the in-situ gradient chemical reaction between Fe and Mo-B-C coating resulted in the formation of a biomimetic ‘brick-mud’ interfacial structure consisting of Mo 2 FeB 2 , Mo 2 BC, and amorphous carbon layers. The “brick-mud” structure, combining soft and hard phases, enhanced the interfacial toughness by effectively deflecting, branching, and prolonging interfacial cracks. Additionally, the transitional diffusion of Fe within the interface layer helpd alleviate the interfacial stress concentration and suppress diamond graphitization. As a result, the optimization of interface bonding contributed to a 26.1 % increase in bending strength and a 156 % enhancement in abrasive ratio of the Fe-based diamond composites, offering a novel strategy for interfacial modification in Fe-based diamond tools.
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2025
·
IF 5.6
Haikuo Lei,Yanli Ruan
The slow kinetics of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) significantly limit the performance and broader applications of zinc-air batteries. To address this, a series of M-N-C catalysts were synthesized using W,O-doped ZIF-67 as a precursor. By modifying the surface electronic structure through doping and improving oxygen intermediate adsorption, these catalysts demonstrated excellent bifunctional catalytic activities for OER and ORR. Among them, W,O-CoNC700 achieved the half-wave potential and overpotential of 0.81 V and 359 mV, respectively. DFT calculations revealed that doping with W atoms affected the d-band center of the Co site, thus enhancing its catalytic ability. The maximum power density of a W,O-CoNC700-based zinc-air battery reached 174.8 mW/cm², outperforming the commercial Pt/C + IrO₂ catalysts. Under constant current discharge at 5 and 10 mA/cm², the cell maintained 1100 and 450 h, respectively.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Hongchun Yu,Maomao He,Zhuo Wang,Feng Han,Yongze Cao,Runze Han,Yang He,Shanshan Li,Yusha Lan,Luran Zhang
Carbon-based magnetic composites derived from metal-organic frameworks (MOFs) have emerged as promising candidates for electromagnetic wave absorption. In this study, graded structured spherical cobalt-iron/carbon (CoFe/C) composites were fabricated via a stepwise in-situ pyrolysis strategy using bimetallic CoFe-MOF precursors. The composite pyrolyzed at 700 ℃ exhibits exceptional microwave absorption properties: it achieves a minimum reflection loss (RL) of −80.3 dB at 9.68 GHz with a 3.00 mm thickness, along with an effective absorption bandwidth (EAB, RL < −10 dB) of 4.8 GHz (7.9–12.7 GHz), fully covering the entire X-band. Notably, when the thickness decreases to 2.20 mm, the EAB expands to 6.7 GHz (11.3–18.0 GHz), spanning the complete Ku-band. Mechanistic analysis reveals that the superior performance arises from two critical factors: optimized impedance matching enabled by synergistic dielectric and magnetic loss mechanisms, and intensified electromagnetic wave scattering through the graded spherical architecture. This work provides a scalable synthesis protocol for bimetallic composites while demonstrating a rational design strategy for high-performance broadband microwave absorbers.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2025
·
IF 3.9
Fang Yuqi,Li Mingzhao,Wang Zi Jin,Liu Xinyu,Yao Shaowei
Metal Bi is considered as a potential anode material for sodium-ion batteries due to its high theoretical specific capacity and low reaction voltage. However, the volume change (244%) during discharge and charge process seriously affects the cycle stability performance. Under this background, the sheet-like structure bismuth based metal-organic framework (Bi-MOF) precursor is prepared by hydrothermal method, and Bi@C composite material is obtained after heat treatment. Due to the unique sheet-like structure and the addition of carbon, the Bi@C composite material can effectively alleviate the volume change during the discharge and charge process. According to the electrochemical performance test, Bi@C electrode material still has high and stable discharge specific capacity of 392.0 mAh g −1 after 1000 cycles at the current density of 0.5 A g −1 , and has excellent rate performance. This work provides an important reference for the development of Bi-based anode materials for sodium-ion battery.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）