JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Lei Cai,Xiang Song,Cheng-Bao Liu,Lan-Yue Cui,Shuo-Qi Li,Fen Zhang,M. Bobby Kannan,Dong-Chu Chen,Rong-Chang Zeng
This work reports the design and preparation of novel organic (polyvinyl alcohol, PVA)-inorganic (neodymium nitrate, Nd(NO 3 ) 3 ) hybrid coatings on micro-arc oxidation (MAO) coating for magnesium (Mg) alloy corrosion protection . X-ray diffractometer , X-ray photoelectron spectroscopy, fourier transform infrared spectroscopy , field emission scanning electron microscope , Energy Dispersive X-ray spectrometer and surface roughness were applied to characterize the chemical composition and surface morphology of the coatings. The corrosion resistance of the coatings was evaluated by electrochemical and salt spray tests. The results suggested that the formation of PVA-Nd 3+ and PVA-Mg 2+ complexes promoted the enrichment of Nd 3+ on the surface, and thereby improved the sealing quality and compactness of the coating. Interestingly, when the coating was damaged, the Nd 3+ ions were transformed to their carbonates and covered the active sites, and thus exhibiting self-healing function. Further, the corrosion resistance of PVA-Nd 3+ modified MAO composite coating on AZ31 Mg alloy was improved.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Energy Materials
·
2022
·Vol. 12
·期 32
·2201600
·
IF 29.698
Zhenyu Chen,Chao Hao,Bowen Yan,Qiuyan Chen,Huiyan Feng,Xiaoqing Mao,Jianmei Cen,Zhi Qun Tian,Panagiotis Tsiakaras,Pei Kang Shen
Traditional calcination usually causes sintering of Pt, which diminishes Pt exposure in proton exchange membrane fuel cell (PEMFC) electrodes. In the present work, a facile self-confined method for synthesizing highly dispersed PtCo-alloy on Co, N co-doped mesoporous carbon (PCN-MC) is developed via a dual-template strategy. Owing to the co-confined effect of Zn in the bimetallic zeolite-based imidazolate framework (ZIF) and Mg(OH) 2 template, ultra-fine 2.7 nm PtCo-alloy with 2–3 atomic-layer Pt-skin nanoparticles are obtained. By adjusting the Co/Zn feeding-ratio in the bimetallic ZIF at 8/7, the alloying degree and nanoparticle size are optimized to achieve an outstanding oxygen reduction reaction activity with a high mass activity (MA) of 0.956 A mg Pt −1 in 0.1 m HClO 4 , about 7.5-fold of that of commercial Pt/C. Furthermore, notable durability is also achieved with 81% retention of the initial MA after 30k cycles conducted between 0.6–1.0 V (versus reversible hydrogen electrode). These features are also verified by a H 2 –Air fuel cell test with an excellent combination of mass activity, power density, and durability. This strategy provides a feasible route for the large-scale synthesis of highly-dispersed PtCo-alloy catalysts.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·
IF 3
Yuhan Chen,Nian Yin,Yunfei Wang,Shanjun Gao,Chunhui Shen
A novel bio-based carbon forming agent (Mg@PA-CS) containing P and N elements was were synthesized using the complexation characteristics of chitosan (CS) and phytate (PA). The flame retardant behavior of poly(lactic acid) (PLA)/Mg@PA-CS/APP composites (addition of 20 wt% of different ratios of Mg@PA-CS and APP to polylactic acid composites) were investigated by the limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetry test (CCT), and thermogravimetric analysis (TGA). Due to the biphasic flame retardant and synergistic effect, since the 20 wt% flame retardant system (Mg@PA-CS:APP = 1:2), PLA composites passed the UL-94 test V-0 rating, reached 34% LOI value. The peak heat release rate (PHRR) and total heat release rate (THR) were reduced to 1/2 of the pure PLA, char residue could be as high as 11.49% at 800°C. Moreover, the flame-retardant mechanism of PLA composites during thermal decomposition was analyzed using a scanning electron microscope (SEM) and the coupling techniques of TGA linked with FT-IR (TG-FTIR).
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Xin-Yu Wang,Yang Hao,Hong-Bo Zhao,Yuan-Ru Guo,Qing-Jiang Pan
The interfacial chemistry of nanocomposite materials is of overarching importance in the separation and purification science; moreover, its understanding helps to guide synthesis, clarify structure-property relationship and unearth novel applications. However, the composites feature rather complicated local structures and hydrogen bonds are often involved in the interface and the vicinity of active sites. In this regard, density functional theory first-principle calculations associated with experimental study have synergistically examined two-dimensional (2D) magnesium hydroxide material with different layers and their adsorption toward cellobiose. Hydrogen bonds are found responsible for the interfacial coupling, which make it vital to cover the dispersion correction in the calculation. The average adsorption energy ranges from −0.29 to −0.35 eV, falling well within the range of reported hydrogen-bonding strength. On the basis of calculated structural/interfacial properties and experimental findings, the 2D Mg(OH) 2 in terms of three-layer model was unraveled to substitute toxic Cd 2+ ion and sorb radioactive UO 2 2+ that is coordinated by water and hydroxyl groups. These reactions are thermodynamically feasible. The ion-exchanging mechanism was proposed for cadmium removal and the outer-sphere adsorption one for uranium extraction.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Hui Yong,Shuai Wang,Jiangwei Ma,Kewei Zhang,Dongliang Zhao,Jifan Hu,Yanghuan Zhang
The Mg-based hydrogen storage alloy with multiple platforms is successfully prepared by ball milling Co powder and Mg-RE-Ni precursor alloy, and its hydrogen storage behavior was investigated in detail by XRD , EDS , TEM, PCI , and DSC methods. The ball-milled alloy consists of the main phase Mg, the catalytic phases Mg 2 Ni, Mg 2 Co as well as a small amount of Mg 12 Ce, and convert into the MgH 2 –CeH 2.73 -Mg 2 NiH 4 –Mg 2 CoH 5 composite after hydrogenation. The composite has three PCI platforms corresponding to the reversible de/hydrogenation reaction of Mg/MgH 2 , Mg 2 Ni/Mg 2 NiH 4 and Mg 6 Co 2 H 11 /Mg 2 CoH 5 . Among them, the transformation between Mg 2 Ni and Mg 2 NiH 4 triggers the “spill-over” effect which promote the decomposition of MgH 2 phases and enhances the hydrogen desorption kinetics. Meanwhile, the conversion of the Mg 6 Co 2 H 11 to Mg 2 CoH 5 phase induces the “chain reaction” effect, which leads to preferential nucleation of Mg phase and improves the hydrogen absorption kinetics. Therefore, the Mg-RE-Ni-Co alloy has a double improvement on hydrogen absorption and desorption kinetics. Concretely, the alloy has an optimal hydrogen absorption temperature of 200 °C, at which it can absorb 5.5 wt. % H 2 within 40 s. Under the conditions, the capacity of absorption almost reaches the maximum reversible value (about 5.6 wt. %). Besides, the alloy has a dehydrogenation activation energy of 67.9 kJ/mol and can desorb 5.0 wt. % H 2 within 60 min at the temperature of 260 °C.
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2021
·Vol. 13
·期 14
·2302
·
IF 4.329
Qingwen Yu,Zhiyuan Meng,Yichao Liu,Zehao Li,Xing Sun,Zheng Zhao
After an osteosarcoma excision, recurrence and bone defects are significant challenges for clinicians. In this study, the curcumin (Cur) loaded chitosan (CS) nanoparticles (CCNP) encapsulated silk fibroin (SF)/hyaluronic acid esterified by methacrylate (HAMA) (CCNPs-SF/HAMA) hydrogel for the osteosarcoma therapy and bone regeneration was developed by photocuring and ethanol treatment. The micro or nanofibers networks were observed in the CCNPs-SF/HAMA hydrogel. The FTIR results demonstrated that alcohol vapor treatment caused an increase in β-sheets of SF, resulting in the high compression stress and Young’s modulus of CCNPs-SF/HAMA hydrogel. According to the water uptake analysis, SF caused a slight decrease in water uptake of CCNPs-SF/HAMA hydrogel while CCNPs could enhance the water uptake of it. The swelling kinetic results showed that both the CCNPs and the SF increased the swelling ratio of CCNPs-SF/HAMA hydrogel. The accumulative release profile of CCNPs-SF/HAMA hydrogel showed that the release of Cur from CCNPs-SF/HAMA hydrogel was accelerated when pH value was decreased from 7.4 to 5.5. Besides, compared with CCNPs, the CCNPs-SF/HAMA hydrogel had a more sustainable drug release, which was beneficial for the long-term treatment of osteosarcoma. In vitro assay results indicated that CCNPs-SF/HAMA hydrogel with equivalent Cur concentration of 150 μg/mL possessed both the effect of anti-cancer and promoting the proliferation of osteoblasts. These results suggest that CCNPs-SF/HAMA hydrogel with superior physical properties and the bifunctional osteosarcoma therapy and bone repair may be an excellent candidate for local cancer therapy and bone regeneration.Keywords:curcumin;hyaluronic acid;silk fibroin;chitosan nanoparticle;MG-63 cells;MC3T3-E1 cells
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY CONVERSION AND MANAGEMENT
·
2019
·
IF 7.181
Fan Zhou,Ningyi Pan,Hongyu Chen,Xiang Xu,Chunhao Wang,Yankun Du,Yang Guo,Zheng Zeng,Liqing Li
Ni-Mg-Al hydrotalcite-derived materials promoted with Ce, Zr or Fe were prepared by the co-precipitation method, which exhibited excellent performance in steam reforming of toluene (SRT) at low temperature. Especially, Fe-doped catalyst had higher catalytic activity and stability at 400 °C, which maintained almost 100% toluene conversion during the SRT reaction (3 h). Moreover, it also had higher hydrogen production and better selectivity for hydrogen production. The physico-chemical characterizations and model simulation indicate its high dispersion of active sites and accessibility of reactants to active sites: uniform dispersion of active sites (SEM, TEM and EDX), large specific surface area (151 m 2 /g), pore volume (0.84 cm 3 /g) and average pore diameter (22.1 nm), small crystallite size (34.9 nm), desirable Ni species reducibility (TPR), high basicity (TPD), low metal carbide formation (XPS), and good adsorption affinity with toluene (−18.391 kJ mol −1 , DFT). Moreover, less carbon was deposited on the Fe-containing catalyst through measuring the amorphous carbon and CNTs by the TG-MS method, which was due to the tip-growth mechanism of CNTs. Considering lower toluene conversion temperature, higher hydrogen yield, and better resistance to carbon deposition, this study may be meaningful in development of SRT at low temperature.
✓ 已验证
产品关联
DOI
高影响因子
Tissue Engineering and Regenerative Medicine
·
2019
·Vol. 16
·期 4
·415-429
·
IF 2.272
Gu Yifan,Zhang Jing,Zhang Xinzhi,Liang Guiping,Xu Tao,Niu Wei
Background: Three-dimensional (3D) printed bone tissue engineering scaffolds have been widely used in research and clinical applications. β-TCP is a biomaterial commonly used in bone tissue engineering to treat bone defects, and its multifunctionality can be achieved by co-doping different metal ions. Magnesium doping in biomaterials has been shown to alter physicochemical properties of cells and enhance osteogenesis. Methods: A series of Mg-doped TCP scaffolds were manufactured by using cryogenic 3D printing technology and sintering. The characteristics of the porous scaffolds, such as microstructure, chemical composition, mechanical properties, apparent porosity, etc., were examined. To further study the role of magnesium ions in simultaneously inducing osteogenesis and angiogenesis, human bone marrow mesenchymal stem cells (hBMSCs) and human umblical vein endothelial cells (HUVECs) were cultured in scaffold extracts to investigate cell proliferation, viability, and expression of osteogenic and angiogenic genes. Results: The results showed that Mg-doped TCP scaffolds have the advantages of precise design, interconnected porous structure, and similar compressive strength to natural cancellous bone. hBMSCs and HUVECs exhibit high proliferation rate, cell morphology and viability in a certain amount of Mg 2+ . In addition, this concentration of magnesium can also increase the expression levels of osteogenic and angiogenic biomarkers. Conclusion: A certain concentration of magnesium ions plays an important role in new bone regeneration and reconstruction. It can be used as a simple and effective method to enhance the osteogenesis and angiogenesis of bioceramic scaffolds, and support the development of biomaterials and bone tissue engineering scaffolds.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2019
·
IF 3.206
Liyang Du,Xuedong Wang,Tingting Liu,Jieyi Li,Junxia Wang,Ming Gao,Huili Wang
Herein, we developed a novel three-layer nanocomposite for adsorption/extraction of organophosphorus pesticides in fruit juice samples. This magnetic nanocomposite was fabricated by coating polydopamine and Mg/Al layered double hydroxides onto NiFe 2 O 4 nanoparticles , which overcomes the shortcomings of low surface area and easy agglomeration associated with conventional Fe-based crystal nanoparticles. Additionally, the higher dispersibility of polydopamine and larger specific surface area of Mg/Al layered double hydroxides are conducive to rapid dispersion and efficient adsorption of organophosphorus pesticides by the synthesized nanocomposites, thereby greatly improving the efficiency of magnetic solid-phase extraction. The extraction method based on as-synthesized nanocomposites provided average extraction recoveries of 84.9% for methamidophos , parathion and phoxim , an increase of ca. 30% and 19% over those of NiFe 2 O 4 and NiFe 2 O 4 @polydopamine, respectively. The main operational parameters were firstly screened and then optimized using Plackett-Burman and central-composite design, respectively. Under optimized conditions, this proposed method yielded low detection limits (0.06–0.13 μg L − 1 ) and high intra- and inter-day precisions (2.7–4.5%). Average extraction recoveries for organophosphorus pesticides were 81.8–94.4% in grape, apple, orange, peach and mango fruit juices. To sum up, it integrates highly efficient preconcentration/extraction/dispersion, as well as rapid separation/collection into one synchronous step, satisfies the technical requirement of modern analytical pretreatment and thus enriches the multi-functional application of Fe-based nanoparticles.
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 55
·43906-43916
·
IF 3.84
Zakir Hussain,Li Daosheng,Li Xi,Kang Jianxiong
A study has been designed for a fluoride adsorbent synthesized by a co-precipitation approach of Mg(II), Al(III) and La(III) salts (MAL) in 2 : 1 : 2 ratios. The prepared material illustrated relatively stable fluoride adsorption potential and an amorphous structure at temperatures lower than 600 °C. The defluoridation capacity of a 2 g L−1 adsorbent dose at room temperature was observed to be between 24.08 to 98.28% for a 10 and 20.66 mg L−1 fluoride solution in a broad pH range (2 to 12), while for a 45.45 mg L−1 solution, it varied between 26.49 to 80.42%. The adsorption process on MAL was endothermic in nature (−ΔG), follows pseudo second order kinetics (R2 = 0.999) and best fitted with a Langmuir sorption isotherm model (R2 = 0.9985). The prepared material was characterized by XRD, SEM, BET, EDX, FTIR and XPS, whereas contact times, sorption kinetics, dosage and the effect of major co-existing anions were carried out for the optimization of the adsorbent. In addition to amphoteric behavior of Al(III) in the composite material, the effect of fluoride concentration and sorbent quantity in a batch process appeared to be important factors in maintaining the near neutral pH of the treated water. Similarly, one other factor, flow rate was found to affect the pH in the column adsorption process. Regeneration of up to 95.71% of the fluoride loaded adsorbent was achieved with a methanol and HCl mixture. The results showed that Al(III) acted as amphoteric reagent and keeps the pH within drinking water range or near neutral.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2017
·
IF 6.395
Kening Sun,Jia Liu,Jie Feng,Hong Yuan,Minjie He,Chunming Xu,Zhenhua Wang,Wang Sun,Jinshuo Qiao
B-site substituted Sr 2 Fe 1.4 X 0.1 Mo 0.5 O 6-δ (SFXM, X = Bi, Al and Mg) are evaluated as anode materials for hybrid direct carbon fuel cells (HDCFCs). The structure, morphology, conductivity and catalytic activity of the as-prepared SFXM anode are systematically investigated. Under a reducing atmosphere, the exsolution of metallic Fe from the SFXM perovskite lattice are demonstrated by the XRD , SEM and TEM observations. Further element valence analysis on reduced SFXM suggests the X doping significantly alters the Fe 3+ /Fe 2+ and Mo 6+ /Mo 5+ ratio, and thus beneficial to the intrinsic conductivity of SFXM. All these advantages are responsible for the good electrochemical performances of SFXM anodes. Meanwhile, among these SFXM anodes, the conductivity, catalytic activity and electrochemical performance all obey the order of SFBM > SFAM > SFMM. The maximum power densities of the La 0.8 Sr 0.2 Ga 0.8 Mg 0.2 O 3 electrolyte supported single cell with SFBM as the anode reaches 399, 287 and 141 mW cm −2 at 800 °C, 750 °C and 700 °C, respectively. Such designed B-site substitution perovskites have great potential to be applied as HDCFC anode materials.
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·
IF 2.7
Kun Liu,Yujing Ling,Xianglong Guan,Ke Hu,Angli Zhang,Kaiqi Liu,Haoyi Li,Guangnian Xu,Xu-Cheng Fu
The commercialization of magnesia-air batteries (Mg-air) necessitates the development of highly efficient, cost-effective, and durable electrocatalysts for oxygen reduction reaction (ORR), replacing expensive and unstable precious metal electrocatalysts. A hard template-assisted synthesis of FeCo nanoparticles immobilized on N-doped porous carbon (Fe-Co-C-N) for the ORR is reported. The half-wave potential of Fe-Co-C-N for ORR (E1/2=0.88 V vs. RHE) is elevated by 40 mV compared to that of 20 wt% Pt/C (E1/2=0.84 vs. RHE). The catalyst exhibits exceptional catalytic performance and remarkable stability. The discharge voltage of the Mg-air battery, utilizing Fe-Co-C-N as the cathode catalyst (1.29 V), surpasses that of the battery employing 20 wt% Pt/C as the cathode catalyst (1.28 V). The Mg-air battery with Fe-Co-C-N as the cathode catalyst exhibited excellent discharge stability and maintained a stable discharge for over 200 hours. The present study offers valuable insights into the structural design and regulatory mechanisms governing the performance of M-N-C catalysts in Mg-air batteries.
✓ 已验证
产品关联
DOI
高影响因子