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Simultaneous removal of total oxidizable carbon,phosphate and various metallic ions from H_(2)O_(2) solution with amino-functionalized zirconia as adsorbents

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Frontiers of Chemical Science and Engineering 2023年第4期17卷 470-482页

作者： Yitong Wang Yue Zhang Li Wang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Zhejiang Institute of Tianjin University Ningbo 315201China

Amino-functionalized zirconia was synthesized by the co-condensation method using zirconium butanol and 3-aminopropyltriethoxy silane for the simultaneous removal of various impurities from aqueous 30% H_(2)O_(2) solution.The results of Fourier transform infrared(FTIR)and Zeta potential showed that the content of N in amino-functionalized zirconia increased with the added amount of 3-aminopropyltriethoxy silane.Accordingly,the removal efficiency of total oxidizable carbon,phosphate and metallic ions from the H_(2)O_(2) solution increased.The adsorbent with an N content of 1.62%exhibited superior adsorption performance.The removal efficiency of 82.7% for total oxidizable carbon,34.2%for phosphate,87.1% for Fe^(3+),83.2%for Al^(3+),55.1%for Ca^(2+)and 66.6%for Mg^(2+),with a total adsorption capacity of 119.6 mg·g^(-1),could be achieved.The studies conducted using simulated solutions showed that the adsorption process of phosphate on amino-functionalized zirconia is endothermic and spontaneous,and the behaviors could be well described by the pseudo-second-order model and Langmuir model with a maximum adsorption capacity of 186.7 mg·g^(-1).The characterizations of the spent adsorbents by Zeta potential,FTIR and X-ray photoelectron spectroscopy revealed that the adsorption mechanism of phosphate is predominantly electrostatic attraction by the protonated functional groups and complementary ligand exchange with zirconium hydroxyl groups.

关键词： adsorption zirconia total oxidizable carbon phosphate metallic ions hydrogen peroxide

Insight into the adsorption behavior and mechanism of trace impurities from H_(2)O_(2)solution on functionalized zirconia by tuning the structure of amino groups

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 83-94页

作者： Yu Meng Yitong Wang Guozhu Li Guozhu Liu Li Wang Key Laboratory for Green Chemical Technology of Ministry Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Primary,secondary and tertiary amino-functionalized zirconia(ZrO_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N)was synthesized by the postgrafting method for the adsorption removal of typical metallic ions,phosphate and total oxidizable carbon from a real H_(2)O_(2)solution.ZrO_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N exhibited similar pore sizes and sequentially increased zeta potentials.The adsorption results of single and binary simulated solutions showed that the removal efficiency increased in the order of Fe^(3+)>Al^(3+)>Ca^(2+)>Na^(+).There is competitive adsorption between metallic ions,and Fe^(3+)has an advantage over the other metals,with a removal efficiency of 90.7%.The coexisting phosphate could promote the adsorption of metallic ions,while total oxidizable carbon had no effect on adsorption.The adsorption results of the real H_(2)O_(2)solution showed that ZrO_(2)-NH_(2)exhibited the best adsorption affinity for metallic ions,as did phosphate and total oxidizable carbon,with a total adsorption capacity of 120.9 mg·g_(-1).Density functional theory calculations revealed that the adsorption process of metallic ions involves electron transfer from N atoms to metals and the formation of N-metal bonds.

关键词： adsorption metallic ion phosphate total oxidizable carbon zirconia H_(2)O_(2)

Advancing dental implants:Bioactive and therapeutic modifications of zirconia

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Bioactive Materials 2022年第7期7卷 161-178页

作者： Divya Chopra Anjana Jayasree Tianqi Guo Karan Gulati Saso Ivanovski The University of Queensland School of DentistryHerston QLD4006Australia

Zirconium-based implants have gained popularity in the dental implant field owing to their corrosion resistance and biocompatibility,attributed to the formation of a native zirconia(ZrO_(2))film.However,enhanced bioactivity and local therapy from such implants are desirable to enable the earlier establishment and improved long-term maintenance of implant integration,especially in compromised patient conditions.As a result,surface modification of zirconium-based implants have been performed using various physical,chemical and biological techniques at the macro-,micro-,and nano-scales.In this extensive review,we discuss and detail the development of Zr implants covering the spectrum from past and present advancements to future perspectives,arriving at the next generation of highly bioactive and therapeutic nano-engineered Zr-based implants.The review provides in-depth knowledge of the bioactive/therapeutic value of surface modification of Zr implants in dental implant applications focusing on clinical translation.

关键词： Zirconium zirconia Implants Surface modification Osseointegration Bioactivity Local therapy

Hetero-phase zirconia encapsulated with Au nanoparticles for boosting electrocatalytic nitrogen reduction

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Chinese Chemical Letters 2024年第5期35卷 509-513页

作者： Xue Xin Qiming Qu Islam E.Khalil Yuting Huang Mo Wei Jie Chen Weina Zhang Fengwei Huo Wenjing Liu Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjing 211816China

Electrocatalytic nitrogen reduction reaction(NRR)is considered as an attractive approach for ammonia synthesis under mild conditions.A bottleneck of NRR is the exploration of efficient catalysts for accelerating reaction kinetics,among which heterogeneous structures possessing distinct atomic arrangement could modify electronic structure,and therefore altering their NRR activity.Here,we report a facile strategy for fabricating hetero-phase metal oxides derived from metal organic framework that are further integrated with Au nanoparticles as NRR catalysts.The phase composition of zirconia can be easily adjusted by simply changing the reaction temperature,where the monoclinic and tetragonal phases with the roughly close proportions have a distinct interface,leading to a strong interaction between Au and ZrO_(2).The enhanced interaction renders Au to be more electropositive and facilitates stronger binding to N_(2).As a result,a remarkable ammonia yield of 22.32μg h^(-1)mg_(cat.)^(-1) and a Faradaic efficiency of 31.92%can be achieved at low overpotential.This work is expected to pave the way for the design of heterogeneous structures and the exploration of hetero-phase nanostructures in boosting the electrocatalytic NRR.

关键词： Hetero-phase Metal-organic framework derivatives zirconia Nitrogen reduction reaction Electrochemistry

A novel porous silica-zirconia coating for improving bond performance of dental zirconia

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2021年第3期22卷 214-222页

作者： Zhiwei SU Mingxing LI Ling ZHANG Chaoyang WANG Leiqing ZHANG Jingqiu XU Baiping FU The Affiliated Hospital of Stomatology School of StomatologyZhejiang University School of Medicineand Key Laboratory of Oral Biomedical Research of Zhejiang ProvinceHangzhou 310006China

Objective:To coat a zirconia surface with silica-zirconia using a dip-coating technique and evaluate its effect on resin-zirconia shear bond strength(SBS).Methods:A silica-zirconia suspension was prepared and used to coat a zirconia surface using a dip-coating technique.One hundred and eighty-nine zirconia disks were divided into three groups according to their different surface treatments(polishing,sandblasting,and silica-zirconia coating).Scanning electron microscopy(SEM),energy dispersive X-ray(EDX),and X-ray diffraction(XRD)were used to analyze the differently treated zirconia surfaces.Different primer treatments(Monobond N,Z-PRIME Plus,and no primer)were also applied to the zirconia surfaces.Subsequently,180 composite resin cylinders(Filtek Z350)were cemented onto the zirconia disks with resin cement(RelyX Ultimate).The SBS was measured after water storage for 24 h or 6 months.The data were analyzed by two-way analysis of variance(ANOVA).Results:SEM and EDX showed that the silica-zirconia coating produced a porous layer with additional Si,and XRD showed that only tetragonal zirconia was on the silica-zirconia-coating surface.Compared with the control group,the resin-zirconia SBSs of the,andblasting group and silica-zirconia-coating group were significantly increased(Pzirconia coating followed by the application of Monobond N produced the highest SBS(Pzirconia SBS(Pzirconia might be a feasible way to improve resin-zirconia bonding.

关键词： Silica-zirconia coating zirconia Bond performance Shear bond strength(SBS)

Ambient flash sintering of reduced graphene oxide/zirconia composites:Role of reduced graphene oxide

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Journal of Materials Science & Technology 2021年第1期60卷 70-76页

作者： Weiwei Xiao Na Ni Xiaohui Fan Xiaofeng Zhao Yingzheng Liu Ping Xiao Gas Turbine Research Institute School of Mechanical EngineeringShanghai Jiao Tong University800 Dongchuan RdShanghai 200240China School of Materials Science and Engineering Shanghai Jiao Tong University800 Dongchuan RdShanghai 200240China

Fabrication of graphene/ceramic composites commonly requires a high-temperature sintering step with long times as well as a vacuum or inert atmosphere,which not only results in property degradation but also significant equipment complexity and manufacturing costs.In this work,the ambient flash sintering behavior of reduced graphene oxide/3 mol% yttria-stabilized ZrO_(2)(rGO/3 YSZ) composites utilizing rGO as both a composite component and a conductive additive is reported.When the sintering condition is carefully optimized,a dense and conductive composite can be achieved at room temperature and in the air within 20 s.The role of the rGO in the FS of the rGO/3 YSZ composites is elucidated,especially with the assistance of a separate investigation on the thermal runaway behavior of the rGO.The work suggests a promising fabrication route for rGO/ceramic composites where the vacuum and furnace are not needed,which is of interest in terms of simplifying the fabrication equipment for energy and cost savings.

关键词： Flash sintering Reduced graphene oxide zirconia Ceramic matrix composites

Powder Characteristics on the Rheological Performance of Resin-based zirconia Suspension for Stereolithography

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无机材料学报 2020年第2期35卷 231-235页

作者： LI Xing-Bang ZHONG He ZHANG Jing-Xian DUAN Yu-Sen JIANG Dong-Liang State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China Suzhou Institute of SICCAS(Shanghai Institute of Ceramics Chinese Academy of Sciences)Taicang 215499China

As for ceramic stereolithography technique,the preparation of suitable resin-based ceramic slurry is of primary importance.In this study,the effects of powder characteristics such as specific surface area,particle size and distribution,particle morphology on the rheological behavior of zirconia resin-based suspensions were investigated intensively.Results show that the specific surface area of the powder is the most important factor affecting slurry viscosity.Choosing low specific surface area and quasi-spherical shaped powder is more likely to obtain low viscosity slurries.In addition,the influence of solid loading on the flow behavior were also studied using Krieger-Dougherty model.zirconia samples with the relative density of(97.83±0.33)%were obtained after sintering at 1550℃.No obvious abnormal grain growth in the microstructure of the sintered body is observed.Results indicate that after the optimization of the processing parameters with the help of rheology characterization,complex-shaped high-quality zirconia parts can be obtained using the stereolithography technique.

关键词： zirconia ceramic stereolithography slurry rheological properties

Hot-pressed graphene nanoplatelets or/and zirconia reinforced hybrid alumina nanocomposites with improved toughness and mechanical characteristics

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Journal of Materials Science & Technology 2020年第5期40卷 135-145页

作者： Iftikhar Ahmad Mohammad Islam Nuha Al Habis Shahid Parvez Center of Excellence for Research in Engineering Materials Deanship of Scientific ResearchKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia Mechanical Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia

This work explains the synergistic contribution of graphene nanoplatelets(GNP)and zirconia ceramic nanoparticles(ZrO2)on the microstructure,mechanical performance and ballistic properties of the alumina(Al2O3)ceramic hybrid nanocomposites.Over the benchmarked monolithic alumina,the hotpressed hybrid nanocomposite microstructure demonstrated 68%lower grain size due to grain pinning phenomenon by the homogenously distributed reinforcing GNP(0.5 wt%)and zirconia(4 wt%)inclusions.Moreover,the hybrid nanocomposite manifested 155%better fracture toughness(KIC)and 17%higher microhardness as well as 88%superior ballistic trait over the monolithic alumina,respectively.The superior mechanical and ballistic performance of the hybrid nanocomposites was attributed to the combined role of zirconia nanoparticles and GNP nanomaterial in refining the microstructure and inducing idiosyncratic strengthening/toughening mechanisms.Extensive combined electron microscopy revealed complicated physical interlocking of the GNP into the microstructure as well as excellent bonding of the GNP with alumina at their interface in the hybrid nanocomposites.We also probed the efficiency of the pull-out and crack-bridging toughening mechanisms through proven quantitative methods.Based on the information extracted from the in-depth SEM/TEM investigation,we outlined schematic models for understating the reinforcing ability as well as toughening mechanisms in the hybrid nanocomposites and meticulously discussed.The hot-pressed hybrid nanocomposites owning high toughness and hardness may have applications in advanced armor technology.

关键词： Graphene Alumina zirconia Toughness Hybrid nanocomposites

Interface tuning of Cu+/CuO by zirconia for dimethyl oxalate hydrogenation to ethylene glycol over Cu/SiO2 catalyst

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Journal of Energy Chemistry 2020年第10期29卷 248-256页

作者： Yujun Zhao Huanhuan Zhang Yuxi Xu Shengnian Wang Yan Xu Shengping Wang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Chemical Engineering Institute for Micromanufacturing.Louisiana Tech UniversityRustonLA 71272USA

An efficient ZrO2-doped Cu/SiO2 catalyst was fabricated through hydrolysis precipitation method(HP)and used to produce ethylene glycol(EG)through dimethyl oxalate(DMO)hydrogenation.The states for zirconia on copper catalyst and roles in DMO hydrogenation were investigated through various characterization tools,including N2 physical adsorption,XRD,H2-TPR,Methyl glycolate-TPD-MS,XPS,XAES as well.Compared with common ammonia evaporation and co-precipitation methods used in catalyst preparation,this HP method is found to effectively suppress the agglomeration and further size growth of copper nanoparticles by enhancing the interactions between copper and zirconia species.More importantly,uniform distribution of ZrO2 dopant is achieved due to the pseudo-homogeneous reactions in the mixing step of catalyst preparation.A proper amount of zirconium dopant helps achieve the desirable proportion of Cu+/(Cu++CuO)for surface copper species,especially promotes the production of Cu+species originated from Cu-ZrO2 species at the interface of copper and zirconia particles.In comparison with Cu+species formed from copper phyllosilicates reduction,the Cu+sites derived from Cu-ZrO2 species show higher adsorption ability of MG,an important intermediate species in ethylene glycol production.These adsorbed MG molecules further react with atomic hydrogen shifted from adjacent metallic copper surface,leading to a higher catalytic behavior.For the EG production via DMO hydrogenation,the turnover frequency(TOF)normalized by CuO species on CuZr/SiO2 catalyst is 1.8 times than that of traditional Cu/SiO2 counterpart.Due to the enhanced synergy effect between Cu+and Cuo active sites,a lower activation energy of ester hydrogenation on this ZrO2-doped Cu/SiO2 catalyst is believed to be responsible for the significant improvement.

关键词： Copper zirconia Hydrogenation Ethylene glycol