JOURNAL OF ALLOYS AND COMPOUNDS
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2024
·
IF 5.8
Jiahuan Cao,Yujia Wu,Yinghuan Fu,Yu Song,Guowen Wang,Hongchao Ma
Photocathodic protection is a promotion strategy for the corrosion protection of metallic materials, and the selection of photocathodic materials is a critical factor in improving the performance of photocathodic protection of metallic materials. Herein, a Ti-P-V-O composite semiconductor photoelectrode with an adjustable porous structure was prepared by the micro-arc oxidation (MAO) method using titanium alloy (TC 4 ) as the matrix and ammonium metavanadate (NH 4 VO 3 ) as the additive. The photogenerated open circuit potential, instantaneous photocurrent density response value, electrochemical impedance spectroscopy, and Tafel curve of as-prepared Ti-P-V-O photo-electrodes were measured after coupling with 304SS to clarify the cathodic protection effect for 304 stainless steel (304SS). It is found that the as-prepared Ti-P-V-O coating photoelectrode has a more negative open circuit potential, a more significant photocurrent density response, more effective interface carrier transport ability, lower resistance, lower compounding efficiency of photogenerated electron/hole pairs, and more negative conduction band level, as compared with that of TiO 2 coatings. Moreover, the optimized Ti-P-V-O photoelectrode (Ti-P-V-O&300 V) exhibited the maximum negative shift of the corrosion potential (410 mV vs. SCE) for coupling with 304 stainless steel. This work presents a new strategy for constructing an efficient coating photo-electrode for photocathodic protection of metallic materials.
研究领域:
材料科学
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电化学
·
腐蚀防护
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DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Yuan-Bin Chen,Siyi Xiong
This article explores the microwave dielectric properties of (La 1-x Nd x ) 2 (Zr 0.96 Ti 0.04 ) 3 (MoO 4 ) 9 (x=0.1,0.3,0.5, and 0.7) ceramics prepared by solid-state reaction. Utilizing the Rietveld refinement technique in XRD, the sample is identified as a trigonal crystal system belonging to the R 3 ¯ c space group. SEM analysis indicates that relative density has a significant impact on the ε r and Q×f of ceramics. The Q×f values of ceramics are closely related to the FWHM of the Raman spectra. At 750℃, (La 0.5 Nd 0.5 ) 2 (Zr 0.96 Ti 0.04 ) 3 (MoO 4 ) 9 ceramic exhibited excellent dielectric properties: ε r = 10.4 (±0.08), Q×f = 149,300 (±3211) GHz, τ f = −34.8 (±0.7) ppm/℃. To gain a deeper understanding of the intrinsic mechanisms governing the microwave dielectric properties of ceramics, analysis based on the P-V-L theory reveals that the La(Nd)-O bond and Mo-O bond contribute significantly to ε r and Q×f, respectively.
研究领域:
材料科学
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陶瓷学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
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IF 16.744
Huan Su,Chao Shan,Xiaolin Zhang,Bingcai Pan
Chemical oxidation is essential in treating P(I)/P(III)-bearing wastewater, while conventional oxidation processes suffer from low selectivity and high cost induced by oxidant reagents. Herein, a low-cost catalyst PdNi 10 was developed to rival the noble metal Pd, which had been known as the only catalyst enabling chemical-free oxidation of P(I)/P(III) into P(V) by ambient O 2 . The PdNi 10 fabricated via optimized method even outperformed Pd in catalytic activity at identical dosage (0.10 g L −1 ), achieving efficient conversion of 1.00 mM of P(I) into P(V) (>94% in 30 min) with wide applicable pH range from 3.0 to 9.0. The aerobic oxidation of P(I) and P(III) over PdNi 10 was confirmed via scavenging experiments to be both dominated by non-radical pathways with apparent activation energies of 44.5 and 21.3 kJ mol −1 , respectively. Interestingly, the individual roles of Ni components of PdNi 10 in the catalytic oxidation were found negligible. The H 2 O-methanol binary solvent experiment suggested that H 2 O mediated the catalytic reaction and the interfacial OH groups as a result of H 2 O dissociation served as the main reactive oxidant species for P(I)/P(III) oxidation. Furthermore, synergistic mechanism was proposed for the Ni and Pd sites with favorable roles in the essential reaction steps of dehydrogenation and hydroxylation, respectively. This study is believed to advance the treatment strategy of P(I)/P(III)-rich wastewater and to shed new light on the development of low-cost catalysts enabling chemical-free aerobic oxidation processes under facile condition.
研究领域:
环境科学
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催化
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化学工程
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材料科学
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DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 14
·5195
·
IF 3.4
Jun Yang,Jinbiao Pang,Xiaofang Luo,Laiyuan Ao,Qiang Xie,Xing Wang,Hongyu Yang,Xianzhong Tang
This work studied the phase constitution, bond characteristics, and microwave dielectric performances of Sr2TiO4ceramics. Based on XRD and Rietveld refinement analysis, pure tetragonal Ruddlesden–Popper type Sr2TiO4ceramic is synthesized at 1425~1525 °C. Meanwhile, the microstructure is dense and without porosity, indicating its high sinterability and densification. Great microwave dielectric performances can be obtained, namely anεrvalue of 39.41, and aQ × fvalue of 93,120 GHz, when sintered at 1475 °C. Under ideal sintering conditions, the extrinsic factors are minimized and can be ignored. Thus, the intrinsic factors are considered crucial in determining microwave dielectric performances. Based on the P–V–L complex chemical bond theory calculation, the largest bond ionicity, and proportions to the bond susceptibility from Sr–O bonds suggest that Sr–O bonds mainly determine the dielectric polarizability. However, the Ti–O bonds show lattice energy about three times larger than Sr–O bonds, emphasizing that the structural stability of Sr2TiO4ceramics is dominated by Ti–O bonds, and the Ti–O bonds are vital in determining the intrinsic dielectric loss. The thermal expansion coefficient value of the Sr2TiO4structure is also mainly decided by Ti–O bonds.Keywords:Sr2TiO4;microwave dielectric properties;P–V–L complex chemical bond theory
研究领域:
材料科学
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物理学
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DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Zezhen Yin,Yun Zhang,Shihua Ding,Tianxiu Song,Xiaoning Li,Jiaying Dan
The solid-phase method was utilized to synthesize LiAl 1- x Be x O 2- x /2 and LiAl 1- x Ga x O 2 ceramics. By Phillips-Van Vechten-Levine (P-V-L) theory, a strong correlation between chemical bond characteristics and microwave dielectric properties was established. X-ray diffraction (XRD) analysis confirmed that all components formed single-phase solid solution with tetragonal structure. Using Be 2+ and Ga 3+ as substitutes, the differences in ionic radii produced diametrically opposite changes in cell volume. The relative density increased to 97.61 % (98.57 %) with the addition of Be 2+ (Ga 3+ ). According to the P-V-L theory, the variation of ε r was influenced by bond ionization. The introduction of different ions caused bond lengths variations, which in turn affected the lattice energy fluctuations. Importantly, this change more than doubled Q×f from 16,268 GHz to 37,015 GHz. Furthermore, the evolution of τ f can be elucidated by the bond energy. Sintered at 1250 °C, both LiAl 0.96 Be 0.04 O 1.98 and LiAl 0.98 Ga 0.02 O 2 demonstrated outstanding microwave dielectric properties, characterized by ε r = 5.83–6.08, Q×f = 32,727∼37,015 GHz, and τ f = −134.8∼-112.4 ppm/°C.
研究领域:
材料科学
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无机化学
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DOI
高影响因子
Membranes
·
2025
·Vol. 15
·期 9
·262
·
IF 3.6
Guibin You,Hongyang Ma,Benjamin S. Hsiao
Elevated phosphorus levels in wastewater created significant environmental concerns, including the degradation of surrounding soil structure, inhibition of plant growth, and potential threats to human health. To address this issue, a self-standing nanofibrous composite membrane based on PA-66/PVA-15%La(OH)3was fabricated via electrospinning, followed by glutaraldehyde (GA) crosslinking and alkali hydrolysis to create an interpenetrating structure, where PA-66 provided the overall mechanical strength of the membrane, while La served as a functional component for the adsorption of phosphate. The chemical composition, surface morphology, thermal stability, and mechanical properties of the resulting membranes were characterized using ATR-FTIR, SEM, TGA, and tensile testing, respectively. Furthermore, the adsorption performance of the membranes was evaluated systematically through static and dynamic adsorption. The Langmuir isotherm model yielded a theoretical maximum adsorption capacity of 21.39 mg/g for phosphate ions. Notably, over 96% of this capacity was retained even in the presence of interfering ions. Moreover, dynamic adsorption experiments demonstrated that the membrane can deal with 1.74 L of phosphate-containing wastewater at a low flow rate of 1.0 mL/min and 1.46 L at a high flow rate of 2.0 mL/min, respectively, while consistently maintaining a phosphate removal efficiency exceeding 90%. A controlled release of phosphate ions from a phosphate-adsorbed membrane was successfully demonstrated using Mougeotia cultivation, implying the potential for phosphorus resource recovery.
研究领域:
环境科学
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材料科学
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水处理技术
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吸附工程
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资源回收
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DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2026
·
IF 6
Zhenjun Qing,Wanting Yang,Haiyan Li
Phase-pure MgP 2 O 6 and NiP 2 O 6 metaphosphate ceramics were synthesized via solid-state reaction. Both crystallize in a monoclinic C2/c structure, with NiP 2 O 6 exhibiting a contracted unit cell due to the smaller ionic radius of Ni 2+ compared to Mg 2+ . The optimum sintering temperature for MgP 2 O 6 was 975 °C, yielding ε r = 5.1, Q × f = 45,300 GHz, τ f = −14.7 ppm/°C, while for NiP 2 O 6 it was 925 °C, yielding ε r = 5.4, Q × f = 66,100 GHz, τ f = −8.7 ppm/°C. The slightly higher ε r of NiP 2 O 6 stems from higher bond ionicity and polarizability density. The superior Q × f is attributed to a higher packing fraction, larger lattice energies, and weaker phonon damping, as evidenced by a narrower Raman FWHM. The improved τ f arises from stronger A–O and P–O bond energies, resisting thermal vibrations. These results indicate MgP 2 O 6 and NiP 2 O 6 as promising low-permittivity microwave ceramics and suggest that A-site cation engineering provides a promising proof-of-concept for tailoring dielectric properties in metaphosphates.
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DOI
高影响因子
Journal of Environmental Sciences
·
2014
·
IF 1.922
Wei Yao,Pinhua Rao,Irene M.C. Lo,Wenqi Zhang,Wenrui Zheng
Pollutants that exist in anionic species are issues of concern in water treatment . Compared to cationic pollutants, the removal of anionic pollutants by adsorption is more difficult because most adsorbents carry predominantly negative charges in neutral and alkaline environments . In this study, a cross-linked chitosan derivative with quaternary ammonium and magnetic properties (QM-chitosan) was prepared and employed to remove chromium(VI) and phosphorus(V) (Cr(VI) and P(V)) from aqueous environments. The QM-chitosan was characterized by Fourier transform infrared spectrometry (FT-IR), thermogravimetric analysis (TGA), energy dispersive X-ray (SEM-EDX) and zeta potential . Batch experiments show that QM-chitosan can effectively remove Cr(VI) and P(V), and the main mechanism was believed to be electrostatic interaction. A pseudosecond-order model was fitted to describe the kinetic processes of Cr(VI) and P(V) removal. The adsorption isotherms of both Cr(VI) and P(V) on the QM-chitosan were well fitted by the Langmuir isotherm equation. The saturated adsorption capacity of P(V) (2.783 mmol/g) was found to be higher than that of Cr(VI) (2.323 mmol/g), resulting from the size of the H 2 PO 4 − ions being smaller than that of the HCrO 4 − ions. However, the theoretical calculation and experimental results showed that QM-chitosan had a stronger affinity for Cr(VI) than P(V). The adsorption–desorption of the QM-chitosan was evaluated, and high regeneration rates were demonstrated.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2026
·Vol. 37
·期 4
·287
·
IF 2.8
Tang Ruxuan,Chen Yuan-Bin,Su Xiuyuan,Tang Ling
With the rapid development of 5G/6G mobile communication technology, microwave dielectric materials are facing increasingly strict performance requirements. As core fundamental materials for modern communication systems, performance optimization of microwave dielectric ceramics has become a research hotspot. Addressing the limitations of single-phase ceramic materials, dense microwave dielectric ceramics of (Nd 1- x La x ) 2 [Zr 0.89 (Bi 0.5 Ta 0.5 ) 0.11 ] 3 (MoO 4 ) 9 ( x = 0.01, 0.03, 0.05, 0.07) were prepared by the conventional solid-state reaction method. The experimental process involved 550 °C pre-sintering followed by gradient sintering at 600–725 °C (4 h holding time). X-ray diffraction (XRD) analysis confirmed that all samples exhibited trigonal crystal structure with \(R\overline{3} c\) space group. The lattice parameters were obtained by Rietveld refinement method. Scanning electron microscopy (SEM) characterization indicates that compactness has a significant impact on the dielectric constant ( ε r ) and the quality factor ( Q × f ). Raman spectroscopy analysis indicated strong associations of ε r and Q × f values with characteristic peak shifts and full width at half maximum ( FWHM ), respectively. When sintered at 675 °C, the NLZBTM ( x = 0.03) ceramics exhibited exceptional comprehensive performance: ε r = 11.24 ± 0.02, Q × f = 116,914 ± 5738 GHz, and τ f = − 37 ± 1.5 ppm/℃. The bond property analysis based on the P–V–L theory shows that the ionicity of the Nd/La–O bond makes the greatest contribution to εᵣ , while the covalency of the Mo–O bond significantly affects the Q × f value and τ f parameter. It is noteworthy that this material achieves low-temperature sintering at 675 °C while maintaining excellent microwave dielectric properties, demonstrating significant potential as a candidate material for low-temperature co-fired ceramics (LTCC).
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高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2026
·Vol. 37
·期 4
·318
·
IF 3.2
Su Xiuyuan,Chen Yuan-Bin,Tang Ruxuan
Based on the Na 0.48 La 0.52 MoO 4 ceramic, this study replaced La 3+ ions with Nd 3+ ions through ion substitution, which significantly increased the Q × f of Na 0.48 La 0.52 MoO 4 and reduced the sintering temperature. The good sintering state of this series of ceramics was demonstrated by scanning electron microscopy (SEM) and density tests. X-ray diffraction (XRD) and Raman spectroscopy results revealed the formation of solid solutions without the presence of secondary phases or impurities. The P–V–L theory indicated that the Na/La/Nd–O bond-to-bond ionicity (fi) contribution was dominant, while the Mo–O bond also played a significant role in the lattice energy ( U ), bond energy ( E ), and thermal expansion coefficient ( α ). Among them, the Na 0.48 La 0.48 Nd 0.04 MoO 4 ceramic achieved the best dielectric performance at 900 °C, with ɛ r = 11.027 ± 0.018, Q × f = 113,805 ± 6,358 GHz, and τ f = − 23.36 ppm/℃. Through ion substitution, these materials all have low sintering temperatures and high Q × f values, making them ideal candidates for low-temperature co-fired ceramics (LTCC).
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2026
·
IF 6
Zhenjun Qing,Jie Duan,Haiyan Li,Yan Xue
A novel NaLaP 2 O 7 ceramic was fabricated via the solid-state reaction method. The sample sintered at 750 °C demonstrated optimal microwave dielectric properties with an ε r of 7.3, a high Q × f value of 23,510 GHz, and a τ f of –79.3 ppm/°C, which are attributed to its high relative density (95.3%) and homogeneous microstructure. Rietveld refinement confirmed a pure orthorhombic phase ( Pnma ). Furthermore, chemical bond analysis based on the P-V-L theory revealed that the high ionicity of La–O bonds predominantly governs the permittivity, while the strong lattice energy and bond energy of P–O bonds are responsible for the high Q × f value and thermal stability, respectively. Raman spectroscopy further verified the highly ordered crystal structure, shown by the characteristic vibrational modes of the P 2 O 7 4- dimer. These findings not only demonstrate that NaLaP 2 O 7 ceramic is a promising low-permittivity candidate for LTCC applications in millimeter-wave communication, but also provide deep insights into the underlying structure–property relationships.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Rui Zhao,Yacong Hu,Wei Ding,Ke Ren,Xinyi Gou,Chun Zhao,Huaili Zheng
Phosphite [P(III)], an emerging eutrophication pollutant, has attracted limited attention in recent years. Owing to the higher solubility and resistance to biotransformation of P(III), oxidation of P(III) to phosphate [P(V)] is considered to be necessary to enhance P(III) removal. Herein, an efficient and regenerable magnetic La 2 (CO 3 ) 3 /CoFe 2 O 4 /biochar composite (LCB) was constructed through a facile one-pot hydrothermal method to treat phosphite-laden wastewater. LCB coupled with peroxymonosulfate (PMS) exhibited satisfactory P(III) removal performance through a one-step process for simultaneous oxidation and adsorption of P(III). The adsorption capacity of LCB/PMS for P(III) (71.94 mg/g) was much higher than that of LCB. LCB/PMS system showed high P(III) removal efficiency of 96.62 %, wide pH ranging from 4.0 to 9.0, and good reusability. It also worked well in the existence of anions and humic acid. The quenching experiments and electron spin resonance tests (ESR) revealed the critical role of SO 4 • - in the P(III) oxidation process. Characterization results demonstrated that electrostatic attraction and ligand exchange were responsible for P(III)/P(V) adsorption. Moreover, LCB/PMS system presented desirable performance in eliminating a series of typical organic and inorganic phosphorus. The LCB/PMS system provides a promising and sustainable technology for the purification of P(III)-contaminated water.
研究领域:
环境科学
·
化学工程
·
水处理技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）