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1.
Small ; : e2405921, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39279613

RESUMO

Hard carbon (HC) stands out as the most prospective anode for sodium-ion batteries (SIBs) with significant potential for commercial applications. However, some long-standing and intractable obstacles, like low first coulombic efficiency (ICE), poor rate capability, storage capacity, and cycling stability, have severely hindered the conversion process from laboratory to commercialization. The above-mentioned issues are closely related to Na+ transfer kinetics, surface chemistry, and internal pseudo-graphitic carbon content. Herein, constructing molybdenum-modified hard carbon solid spheres (Mo2C/HC-5.0), both the ion transfer kinetics, surface chemistry, and internal pseudo-graphitic carbon content are comprehensively improved. Specifically, Mo2C/HC-5.0 with higher pseudo-graphitic carbon content provides a large number of active sites and a more stable layer structure, resulting in improved sodium storage capacity, rate performance, and cycling stability. Moreover, the lower defect density and specific surface area of Mo2C/HC-5.0 further enhance ICE and sodium storage capacity. Consequently, the Mo2C/HC-5.0 anode achieves a high capacity of 410.7 mA h g-1 and an ICE of 83.9% at 50 mA g-1. Furthermore, the material exhibits exceptional rate capability and cycling stability, maintaining a capacity of 202.8 mA h g-1 at 2 A g-1 and 214.9 mA h g-1 after 800 cycles at 1 A g-1.

2.
Langmuir ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289813

RESUMO

Hydrogel electrolytes have been widely explored in flexible zinc batteries owing to their considerable mechanical strain and water-retaining properties. However, it is difficult to balance the contradiction between the ionic conductivity and the mechanical strength due to the deterioration of structural stability with the addition of electrolyte salts. To address this, we designed a coassembling organic-inorganic hydrogel (P-P/M) based on poly(vinyl alcohol)-polyacrylamide (P-P) interpenetrating matrix decorated with Zn-based montmorillonite (Zn-MMT). The Zn-MMT with overall negative potential can attract and regulate the transport of Zn2+, while the Brønsted/Lewis acid sites with positive polarizations offer anchoring sites for anions, which increases the cation transference number and reduces byproduct formation. Moreover, the formation of hydrogen bonds in the hydrogel can weaken the contact between free water molecules and the zinc cations, which effectively suppresses the corrosion of zinc foil. Consequently, the Zn//Zn cell with P-P/M electrolyte delivers a long cycle life of 2400 h at 0.5 mA cm-2. The good mechanical properties of the P-P/M hydrogel boost its application in flexible pouch cells even under bending and cutting conditions. This study provides an effective approach to designing organic-inorganic hydrogel electrolytes for long-life flexible zinc batteries.

3.
Angew Chem Int Ed Engl ; : e202409957, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39034299

RESUMO

The practical application of aqueous zinc-ion batteries (ZIBs) indeed faces challenges primarily attributed to the inherent side reactions and dendrite growth associated with the Zn anode. In the present work, N-Methylmethanesulfonamide (NMS) is introduced to optimize the transfer, desolvation, and reduction of Zn2+, achieving highly stable and reversible Zn plating/stripping. The NMS molecule can substitute one H2O molecule in the solvation structure of hydrated Zn2+ and be preferentially chemisorbed on the Zn surface to protect Zn anode against corrosion and hydrogen evolution reaction (HER), thereby suppressing byproducts formation. Additionally, a robust N-rich organic and inorganic (ZnS and ZnCO3) hybrid solid electrolyte interphase is in situ generated on Zn anode due to the decomposition of NMS, resulting in enhanced Zn2+ transport kinetics and uniform Zn2+ deposition. Consequently, aqueous cells with the NMS achieve a long lifespan of 2300 h at 1 mA cm-2 and 1 mAh cm-2, high cumulative plated capacity of 3.25 Ah cm-2, and excellent reversibility with an average coulombic efficiency (CE) of 99.7% over 800 cycles.

4.
Angew Chem Int Ed Engl ; 63(24): e202403050, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38579168

RESUMO

Unstable Zn interface with serious detrimental parasitic side-reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc-ion batteries. The interface stability was closely related to the electrolyte configuration and Zn2+ depositional behavior. In this work, a unique Zn-ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn-ions and guide the Zn-ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc-ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc-ion distribution by using its positively charged -NR4 + groups. While the negatively charged -SO3 - groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn-ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side-reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mA cm-2, 0.25 mAh cm-2). Additionally, based on this strategy, the NH4V4O10||Zn pouch-cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4 % capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch-cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles.

5.
Angew Chem Int Ed Engl ; 63(21): e202402833, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38535776

RESUMO

Aqueous zinc-metal batteries (AZMBs) usually suffered from poor reversibility and limited lifespan because of serious water induced side-reactions, hydrogen evolution reactions (HER) and rampant zinc (Zn) dendrite growth. Reducing the content of water molecules within Zn-ion solvation sheaths can effectively suppress those inherent defects of AZMBs. In this work, we originally discovered that the two carbonyl groups of N-Acetyl-ϵ-caprolactam (N-ac) chelating ligand can serve as dual solvation sites to coordinate with Zn2+, thereby minimizing water molecules within Zn-ion solvation sheaths, and greatly inhibit water-induced side-reactions and HER. Moreover, the N-ac chelating additive can form a unique physical barrier interface on Zn surface, preventing the harmful contacting with water. In addition, the preferential adsorption of N-ac on Zn (002) facets can promote highly reversible and dendrite-free Zn2+ deposition. As a result, Zn//Cu half-cell within N-ac added electrolyte delivered ultra-high 99.89 % Coulombic efficiency during 8000 cycles. Zn//Zn symmetric cells also demonstrated unprecedented long life of more than 9800 hours (over one year). Aqueous Zn//ZnV6O16 ⋅ 8H2O (Zn//ZVO) full-cell preserved 78 % capacity even after ultra-long 2000 cycles. A more practical pouch-cell was also obtained (90.2 % capacity after 100 cycles). This method offers a promising strategy for accelerating the development of highly efficient AZMBs.

6.
Angew Chem Int Ed Engl ; 63(34): e202406906, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38819764

RESUMO

Eutectic electrolytes show potential beyond conventional low-concentration electrolytes (LCEs) in zinc (Zn)-ion capacitors (ZICs) yet suffer from high viscosity and sluggish kinetics. Herein, we originally propose a universal theory of intrinsically decoupling to address these issues, producing a novel electrolyte termed "quasi-eutectic" electrolyte (quasi-EE). Joint experimental and theoretical analyses confirm its unique solution coordination structure doped with near-LCE domains. This enables the quasi-EE well inherit the advanced properties at deep-eutectic states while provide facilitated kinetics as well as lower energy barriers via a vehicle/hopping-hybridized charge transfer mechanism. Consequently, a homogeneous electroplating pattern with much enhanced Sand's time is achieved on the Zn surface, followed by a twofold prolonged service-life with drastically reduced concentration polarization. More encouragingly, the quasi-EE also delivers increased capacitance output in ZICs, which is elevated by 12.4 %-144.6 % compared to that before decoupling. Furthermore, the pouch cell with a cathodic mass loading of 36.6 mg cm-2 maintains competitive cycling performances over 600 cycles, far exceeding other Zn-based counterparts. This work offers fresh insights into eutectic decoupling and beyond.

7.
Small ; 19(49): e2303457, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37394714

RESUMO

Water-induced parasitic reactions and uncontrolled dendritic Zn growth are long-lasting tricky problems that severely hinder the development of aqueous zinc-metal batteries. Those notorious issues are closely related to electrolyte configuration and zinc-ion transport behavior. Herein, through constructing aligned dipoles induced electric-field on Zn surface, both the solvation structure and transport behavior of zinc-ions are fundamentally changed. The vertically ordered zinc-ion migration trajectory and gradually concentrated zinc-ion achieved inside the polarized electric-field remarkably eliminate water related side-reactions and Zn dendrites. Zn-metal under the polarized electric-field demonstrated significantly improve reversibility and a dendrite-free surface with strong (002) Zn deposition texturing. Zn||Zn symmetric cell delivers greatly prolonged lifespan up to 1400 h (17 times longer than that of the cell based on bare Zn) while the Zn||Cu half-cell demonstrate ultrahigh 99.9% coulombic efficiency. NH4 V4 O10 ||Zn half-cell delivered exceptional-high 132 mAh g-1 capacity after ultralong 2000 cycles (≈100% capacity retention). In addition, MnO2 ||Zn pouch-cell under aligned dipoles induced electric-field maintains 87.9% capacity retention after 150 cycles under practical condition of high MnO2 mass loading (≈10 mg cm-2 ) and limited N/P ratio. It is considered that this new strategy can also be implemented to other metallic batteries and spur the development of batteries with long-lifespan and high-energy-density.

8.
Small ; 19(21): e2207764, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36869407

RESUMO

Lithium-metal shows promising prospects in constructing various high-energy-density lithium-metal batteries (LMBs) while long-lasting tricky issues including the uncontrolled dendritic lithium growth and infinite lithium volume expansion seriously impede the application of LMBs. In this work, it is originally found that a unique lithiophilic magnetic host matrix (Co3 O4 -CCNFs) can simultaneously eliminate the uncontrolled dendritic lithium growth and huge lithium volume expansion that commonly occur in typical LMBs. The magnetic Co3 O4 nanocrystals which inherently embed on the host matrix act as nucleation sites and can also induce micromagnetic field and facilitate a targeted and ordered lithium deposition behavior thus, eliminating the formation of dendritic Li. Meanwhile, the conductive host can effectively homogenize the current distribution and Li-ion flux, thus, further relieving the volume expansion during cycling. Benefiting from this, the featured electrodes demonstrate ultra-high coulombic efficiency of 99.1% under 1 mA cm-2 and 1 mAh cm-2 . Symmetric cell under limited Li (10 mAh cm-2 ) inspiringly delivers ultralong cycle life of 1600 h (under 2 mA cm-2 , 1 mAh cm-2 ). Moreover, LiFePO4 ||Co3 O4 -CCNFs@Li full-cell under practical condition of limited negative/positive capacity ratio (2.3:1) can deliver remarkably improved cycling stability (with 86.6% capacity retention over 440 cycles).

9.
Langmuir ; 38(26): 8012-8020, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35715215

RESUMO

Ca2+ overload has attracted an increasing attention due to its benefit of precise cancer therapy, but its efficacy is limited by the strong Ca2+ excretion of cancer cells. Moreover, monotherapy of Ca2+ overload usually fails to treat tumors satisfactorily. Herein, we develop a multifunctional nanosystem that could induce Ca2+ overload by multipathway and simultaneously produce chemotherapy for synergistic tumor therapy. The nanosystem (CaMSN@CUR) is prepared by synthesizing a Ca-doped mesoporous silica nanoparticle (CaMSN) followed by loading the anticancer drug curcumin (CUR). CaMSN serves as the basis Ca2+ generator to induce Ca2+ overload directly in the intracellular environment by acid-triggered Ca2+ release, while CUR could not only exhibit chemotherapy but also facilitate Ca2+ release from the endoplasmic reticulum to the cytoplasm and inhibit Ca2+ efflux out of cells to further enhance Ca2+ overload. The in vitro and in vivo results show that CaMSN@CUR could exhibit a remarkable cytotoxicity against 4T1 cells and significantly inhibit tumor growth in 4T1 tumor-bearing mice via the synergy of Ca2+ overload and CUR-mediated chemotherapy. It is expected that the designed CaMSN@CUR has a great potential for effective tumor therapy.


Assuntos
Antineoplásicos , Curcumina , Nanopartículas , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Curcumina/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Camundongos , Dióxido de Silício
10.
Small ; 17(40): e2101944, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34469065

RESUMO

In situ electrochemical activation brings unexpected electrochemical performance improvements to electrode materials, but the mechanism behind it still needs further study. Herein, an electrochemically in situ defect induction in close-packed lattice plane of vanadium nitride oxide (VNx Oy ) in aqueous zinc-ion battery is reported. It is verified by theoretical calculation and experiment that the original compact structure is not suitable for the insert of Zn2+ ion, while a highly active one after the initial electrochemical activization accompanied by the in situ defect induction in close-packed lattice plane of VNx Oy exhibits efficient zinc ion storage. As expected, activated VNx Oy can achieve very high reversible capacity of 231.4 mA h g-1 at 1 A g-1 and cycle stability upto 6000 cycles at 10 A g-1 with a capacity retention of 94.3%. This work proposes a new insight for understanding the electrochemically in situ transformation to obtain highly active cathode materials for the aqueous zinc-ion batteries.

11.
Small ; 14(48): e1803015, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30328265

RESUMO

Layered serpentine Ni3 Ge2 O5 (OH)4 is compositionally active and structurally favorable for adsorption and diffusion of reactants in oxygen evolution reactions (OER). However, one of the major problems for these materials is limited active sites and low efficiency for OER. In this regard, a new catalyst consisting of layered serpentine Ni3 Ge2 O5 (OH)4 nanosheets is introduced via a controlled one-step synthetic process where the morphology, size, and layers are well tailored. The theoretical calculations indicate that decreased layers and increased exposure of (100) facets in serpentine Ni3 Ge2 O5 (OH)4 lead to much lower Gibbs free energy in adsorption of reactive intermediates. Experimentally, it is found that the reduction in number of layers with minimized particle size exhibits plenty of highly surface-active sites of (100) facets and demonstrates a much enhanced performance in OER than the corresponding multilayered nanosheets. Such a strategy of tailoring active sites of serpentine Ni3 Ge2 O5 (OH)4 nanosheets offers an effective method to design highly efficient electrocatalysts.

12.
Nanomedicine ; 14(5): 1619-1628, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29698728

RESUMO

Keratinocyte growth factor (KGF) has been demonstrated to specifically stimulate the multiplication and migration of keratinocytes. However, due to rapid degradation, the results of topical application of growth factors on wounds are unsatisfactory. In this study, we cross-linked KGF to the surface of gold nanoparticles (GNPs) and explored their effects on wound healing. The as-synthesized nanocomposite (KGF-GNPs) displayed good colloidal stability, decent biocompatibility as well as negligible cellular cytotoxicity. The in vitro cellular experimental results demonstrated that KGF-GNPs could effectively promote the proliferation of keratinocytes in contrast to bare GNPs or KGF. Furthermore, in animal full-thickness wound model, KGF-GNPs are more conducive to wound healing than bare GNPs or KGF. KGF-GNPs enhanced wound healing by promoting wound re-epithelialization rather than granulation. The superior biocompatibility, colloidal depressiveness and biological activity of this nanocomposite indicate that it could be utilized as a promising wound healing drug for clinical application in the future.


Assuntos
Fator 7 de Crescimento de Fibroblastos/administração & dosagem , Ouro/química , Queratinócitos/citologia , Nanopartículas Metálicas/administração & dosagem , Cicatrização , Administração Tópica , Animais , Células Cultivadas , Feminino , Fator 7 de Crescimento de Fibroblastos/química , Queratinócitos/efeitos dos fármacos , Nanopartículas Metálicas/química , Ratos , Ratos Sprague-Dawley
13.
Nanotechnology ; 27(46): 46LT01, 2016 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-27734810

RESUMO

We report the synthesis of three-dimensional (3D) urchin-like Nb2O5 microstructures by a facile hydrothermal approach with subsequent annealing treatment. As anode materials for lithium-ion batteries, the 3D urchin-like Nb2O5 microstructures exhibit superior electrochemical performance with excellent rate capability as well as long-term cycling stability. The electrode delivers high capacity of 131 mA h g-1 after 1000 cycles at a high current density of 1 A g-1. The excellent electrochemical performance suggests the 3D urchin-like Nb2O5 microstructures may be a promising anode candidate for high-power lithium ion batteries.

14.
Nanotechnology ; 27(30): 305404, 2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27320105

RESUMO

Highly porous hierarchical V2O5 cuboids have been synthesized by a template-free PVP-assisted polyxol method and the formation mechanism is studied. The cuboids are assembled from numerous mesoporous nanoplates and the preferred orientation of each single nanoplate exposes the 〈110〉 facets, facilitating lithium-ion diffusion by offering a prior channel. This material exhibits a high capacity of 143 mA h g(-1), high rate capacity of 10 C and long life cycling performance up to 1000 cycles. The excellent electrochemical performance of V2O5 cuboid electrodes is due to its unique porous cuboid morphology and optimized structural stability upon cycling. This research provides an effective route to the construction of complex porous architectures assembled from nanocrystals through a surfactant-assisted synthesis method.

15.
ChemSusChem ; 17(3): e202301268, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-37845180

RESUMO

Solid-state batteries (SSBs) are considered to be one of the most promising candidates for next-generation energy storage systems due to the high safety, high energy density and wide operating temperature range of solid-state electrolytes (SSEs) they use. Unfortunately, the practical application of SSEs has rarely been successful, which is largely attributed to the low chemical stability and ionic conductivity, ineluctable solid-solid interface issues including limited ion transport channels, high energy barriers, and poor interface contact. A comprehensive understanding of ion transport mechanisms of various SSEs, interactions between fillers and polymer matrixes and the role of the interface in SSBs are indispensable for rational design and performance optimization of novel electrolytes. The categories, research advances and ion transport mechanism of inorganic glass/ceramic electrolytes, polymer-based electrolytes and corresponding composite electrolytes are detailly summarized and discussed. Moreover, interface contact and compatibility between electrolyte and cathode/anode are also briefly discussed. Furthermore, the electrochemical characterization methods of SSEs used in different types of SSBs are also introduced. On this basis, the principles and prospects of novel SSEs and interface design are curtly proposed according to the development requirements of SSBs. Moreover, the advanced characterizations for real-time monitoring of interface changes are also brought forward to promote the development of SSBs.

16.
Chem Sci ; 15(12): 4581-4589, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38516097

RESUMO

The realization of high energy is of great importance to unlock the practical potential of zinc-iodine batteries. However, significant challenges, such as low iodine loading (mostly less than 50 wt%), restricted iodine reutilization, and severe structural pulverization during cycling, compromise its intrinsic features. This study introduces an optimized, fully zincified zinc iodide loaded onto a hierarchical carbon scaffold with high active component loading and content (82 wt%) to prepare a thick cathode for enabling high-energy Zn-I2 batteries. The synergistic interactions between nitrogen heteroatoms and cobalt nanocrystals within the porous matrix not only provide forceful chemisorption to lock polyiodide intermediates but also invoke the electrocatalytic effects to manipulate efficient iodine conversion. The ZnI2 cathode could effectively alleviate continuous volumetric expansion and maximize the utilization of active species. The electrochemical examinations confirm the thickness-independent battery performance of assembled Zn-I2 cells due to the ensemble effect of composite electrodes. Accordingly, with a thickness of 300 µm and ZnI2 loading of up to 20.5 mg cm-2, the cathode delivers a specific capacity of 92 mA h gcathode-1 after 2000 cycles at 1C. Moreover, the Zn-I2 pouch cell with ZnI2 cathode has an energy density of 145 W h kgcathode-1 as well as a stable long cycle life.

17.
Adv Mater ; 36(26): e2403765, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593813

RESUMO

Zinc metal suffers from violent and long-lasting water-induced side reactions and uncontrollable dendritic Zn growth, which seriously reduce the coulombic efficiency (CE) and lifespan of aqueous zinc-metal batteries (AZMBs). To suppress the corresponding harmful effects of the highly active water, a stable zirconium-based metal-organic framework with water catchers decorated inside its sub-nano channels is used to protect Zn-metal. Water catchers within narrow channels can constantly trap water molecules from the solvated Zn-ions and facilitate step-by-step desolvation/dehydration, thereby promoting the formation of an aggregative electrolyte configuration, which consequently eliminates water-induced corrosion and side reactions. More importantly, the functionalized sub-nano channels also act as ion rectifiers and promote fast but even Zn-ions transport, thereby leading to a dendrite-free Zn metal. As a result, the protected Zn metal demonstrates an unprecedented cycling stability of more than 10 000 h and an ultra-high average CE of 99.92% during 4000 cycles. More inspiringly, a practical NH4V4O10//Zn pouch-cell is fabricated and delivers a capacity of 98 mAh (under high cathode mass loading of 25.7 mg cm-2) and preserves 86.2% capacity retention after 150 cycles. This new strategy in promoting highly reversible Zn metal anodes would spur the practical utilization of AZMBs.

18.
Chemistry ; 19(2): 494-500, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23193070

RESUMO

Nanosheet-assembled hierarchical V(2)O(5) hollow microspheres are successfully obtained from V-glycolate precursor hollow microspheres, which in turn are synthesized by a simple template-free solvothermal method. The structural evolution of the V-glycolate hollow microspheres has been studied and explained by the inside-out Ostwald-ripening mechanism. The surface morphologies of the hollow microspheres can be controlled by varying the mixture solution and the solvothermal reaction time. After calcination in air, hierarchical V(2)O(5) hollow microspheres with a high surface area of 70 m(2) g(-1) can be obtained and the structure is well preserved. When evaluated as cathode materials for lithium-ion batteries, the as-prepared hierarchical V(2)O(5) hollow spheres deliver a specific discharge capacity of 144 mA h g(-1) at a current density of 100 mA g(-1), which is very close to the theoretical capacity (147 mA h g(-1)) for one Li(+) insertion per V(2)O(5) . In addition, excellent rate capability and cycling stability are observed, suggesting their promising use in lithium-ion batteries.


Assuntos
Fontes de Energia Elétrica , Glicolatos/química , Lítio/química , Microesferas , Compostos de Vanádio/química , Vanádio/química , Técnicas de Química Sintética , Eletroquímica , Eletrodos
19.
J Nanosci Nanotechnol ; 13(3): 2362-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23755692

RESUMO

The preparation of the superhydrophobic surface on aluminum alloy by anodizing and polypropylene (PP) coating was reported. Both the different anodizing process and different PP coatings of aluminum alloy were investigated. The effects of different anodizing conditions, such as electrolyte concentration, anodization time and current on the superhydrophobic surface were discussed. By PP coating after anodizing, a good superhydrophobic surface was facilely fabricated. The optimum conditions for anodizing were determined by orthogonal experiments. After the aluminium-alloy was grinded with 600# sandpaper, pretreated by 73 g/L hydrochloric acid solution at 1 min, when the concentration of sulfuric acid was 180 g/L, the concentration of oxalic acid was 5 g/L, the concentration of potassium dichromate was 10 g/L, the concentration of chloride sodium was 50 g/L and 63 g/L of glycerol, anodization time was 20 min, and anodization current was 1.2 A/dm2, anodization temperature was 30-35 degrees C, the best micro-nanostructure aluminum alloy films was obtained. On the other hand, the PP with different concentrations was used to the PP with different concentrations was used to coat the aluminum alloy surface after anodizing. The results showed that the best superhydrophobicity was achieved by coating PP, and the duration of the superhydrophobic surface was improved by modifying the coat the aluminum alloy surface after anodizing. The results showed that the best superhydrophobicity was surface with high concentration PP. The morphologies of micro/nano-structure superhydrophobic surface were further confirmed by scanning electron microscope (SEM). The material of PP with the low surface free energy combined with the micro/nano-structures of the surface resulted in the superhydrophobicity of the aluminum alloy surface.

20.
J Nanosci Nanotechnol ; 13(10): 6760-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24245140

RESUMO

A simple and novel approach has been developed to obtain a microporous film with compound nanoparticles on the surface of aluminum alloy substrate using the galvanic corrosion method. The wettability of the surface changes from hydrophilicity to superhydrophobicity after chemical modification with stearic acid (SA). The water contact angle (WCA) and sliding angle (WSA) of superhydrophobic aluminum alloy surface (SAAS) are 154 degrees and 9 degrees, respectively. The roughness of the aluminum substrate increases after the oxidation reaction. The porous aluminum matrix surface is covered with irregularly shaped holes with a mean radius of about 15 microm, similar to the surface papillae of natural Lotus leaf, with villus-like nanoparticles array on pore surfaces. The superhydrophobic property is attributed to this special surface morphology and low surface energy SA. X-ray powder diffraction (XRD) pattern and Energy Dispersive X-Ray Spectroscopy (EDS) spectrum indicate that Al2O3, Al(OH)3 and AIO(OH) has been formed on the surface of aluminum substrate after the oxidation reaction. The Raman spectra indicate that C-H bond from SA and the Al-O are formed on the SAAS. The as-formed SAAS has good stability.

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