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A Biomimetic Tooth Replicate That Is Hard,Damage-Tolerant,and Self-Healable

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CCS Chemistry 2023年第1期5卷 95-105页

作者： Ying Yan Kai Niu Wenbo Zhang Weiming Sun Yue Jiang Zhonghao Jiang Lijuan Zhao Ming Yang Baosheng Li Ying Hou Guangshe Li Ming Yang shouhua feng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012 Department of Otorhinolaryngology Head and Neck Surgery The First Hospital of Jilin UniversityChangchun 130021 Key Laboratory of Automobile Materials College of Materials Science and EngineeringJilin UniversityChangchun 130025 Key Laboratory of Bionic Engineering of Ministry of Education College of Biological and Agricultural EngineeringJilin UniversityChangchun 130022 Department of Molecular Biology College of Basic Medical SciencesJilin UniversityChangchun 130021 Department of Dental Implantology Hospital of StomatologyJilin UniversityChangchun 130021

Hard materials typically lack the mechanism of energy dissipation and cannot self-heal.Nature addresses this challenge by creating multiscale interfaces between high-contrast materials,namely minerals and biopolymers.Inspired by the enamel-dentin junction in nature,an enamel-like crown consisting ofβFeOOH nanocolumns is interdigitated with a flexible self-healing layer.The iron oxide top layer has exceptionally high modulus and hardness,which is more resistant to cyclic deformation than the bottom layer.The latter however provides an additional pathway for viscous and plastic energy dissipation and enables self-healing by allowing upward polymer diffusion to seal the damage.Picture-frame crack patterns were observed under large loading conditions using microindentation,which localizes the damage at the indentation site.The bending properties can be optimized by varying the thickness of the bottom layer,and the crack induced by bending can be effectively captured at the interface without any delamination.The biomimetic tooth replicate is highly adhesive to a ceramic surface and shows an obvious inhibition effect against Streptococcus mutans,a significant contributor to tooth decay.Combined with ultralow thermal diffusivity,this has great potential as dental material.Learning from nature,our work thus provides a powerful pathway to broadening the scope of synthetic materials for dental replicates.

关键词： biomimetics molecular assembly enamel-dentin interface mechanical properties self-healing

Enhanced CO catalytic oxidation by Sr reconstruction on the surface of LaxSr1-xCoO3-δ

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Science Bulletin 2017年第9期62卷 658-664页

作者： Xiyang Wang Keke Huang Jingyu Qian Yingge Cong Chengda Ge shouhua feng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry filin University Changchun 130012 China State Key Laboratory of Supramolecular Structure and Materials College of Chemistry filin University Changchun 130012 China

Surface electronic structure of solid materials plays a critical role in heterogeneous catalysis. However,surface chemical composition of the perovskite oxides is usually dominated by segregated A-site cations and the amount of oxygen vacancies is relatively low, which seriously restricts their catalytic oxidation property. Here, we prepare perovskite La_xSr_(1-x)CoO_(3-δ)(x = 0.3, 0.5, 0.7) with different Sr doping amount and experiment results show that perovskite LSCO with higher content of surface Sr possesses more oxygen vacancies and better catalytic activity. On this basis, we develop a new experimental strategy to create more surface oxygen vacancies to promote their CO catalytic activity. In this method, we use high active hydrogen atoms(BH^(4-)) as reductant to realize surface in-situ chemical composite modification of La_xSr_(1-x)CoO_(3-δ)(x = 0.3, 0.5, 0.7), which causes their surface reconstruction(surface Sr enrichment).The regulation mainly focuses on the atomic layer level without damaging their bulk phase structure.Different from traditional high temperature annealing under reducing atmosphere, this method is high-efficiency, green and controllable. Furthermore, we study the surface reconstruction process and demonstrated that it is atomic layer engineering on the surface of La_xSr_(1-x)CoO_(3-δ)(x = 0.3, 0.5, 0.7) by X-ray photoelectron spectroscopy(XPS) and X-ray absorption fine structure(XAFS). Our experiment results also show that these samples treated by this method exhibit superior activity for CO oxidation compared with original samples.

关键词： Surface reconstruction KBH4 Perovskite oxides Oxygen vacancies CO oxidation

Manipulation and observation of atomic-scale superlattices in perovskite manganate

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Chinese Chemical Letters 2023年第12期34卷 481-485页

作者： Xiyang Wang Keke Huang Xiaofeng Wu Long Yuan Liping Li Guangshe Li shouhua feng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin Provincial International Cooperation Key Laboratory of Advanced Inorganic Solid Functional Materialsjilin UniversityChangchun 130012China

Superlattices in crystals,particularly in perovskite oxides with strong correlation effects,can create new states of matter and produce peculiar physicochemical phenomena.However,the newfangled perovskite superlattices depend on physical deposition with unit-cell precision.It has been challenging to explore a new suitable chemical method to tailor perovskite superlattices.Herein,we present a new bottomup strategy to precisely prepare atomic-scale oxide superlattices of(LaMnO_(3))_(1)-(La_(1-x-y)Ca_(x)K_(y)MnO_(3))_(2)in a monodispersed perovskite La_(0.66)Ca_(0.29)K_(0.05)MnO_(3)(LCKMO).The special atomic-scale perovskite superlattices are demonstrated using SAED,HAADF-STEM,XRD,and atomic-resolution elemental mapping.Our experiments reveal that the perovskite superlattices can be fabricated under extreme hydrothermal conditions utilizing ultra-high concentrations of KOH.An approximate molten salt system in the hydrothermal process can induce the disproportionation reaction of MnO_(2)solids,which is vital to the growth of ordered perovskite superlattices.This work not only clarifies the hydrothermal growth process of perovskite oxides in extreme conditions,but also proposes a novel engineering route toward perovskite superlattices.

关键词： Perovskite oxides Hydrothermal Ordered superstructure Perovskite superlattice Disproportionation reaction

A Self-Strengthening Epidermis-Like Smart Coating Enabled by Dynamic Iron Sequestration

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CCS Chemistry 2021年第11期3卷 2655-2668页

作者： Xiaodong Qi Lei Yang Ying Hou Jiaqi Zhu Ming Yang shouhua feng Key Laboratory of Microsystems and Micronanostructures Manufacturing Harbin Institute of TechnologyHarbin 150080 State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012

Living organisms rely on materials sequestration from the environment to strengthen their bodies.Such constant activity provides necessary supplies for critical biological functions,which is difficult by man-made structures due to the lack of a dynamic sequestration mechanism.In this study,it is shown that an epidermis-like smart coating can respond to changes in salinity to allow a spontaneous and progressive strengthening when supported by steel as a sustained iron source.The self-strengthening is enabled by reaction-coupled diffusion,which makes possible the dynamic sequestration of iron from the in situ rusted steel,partially mimicking the iron accumulation process in a mussel.The emergence of iron-phenolic coordination bonds continuously improves modulus,hardness,and adhesion,achieving a strengthening efficiency comparable to mussel byssus.Interestingly,the bilayer design ensures long-term self-healing performance even during strengthening and a mechanically robust anticorrosion coating with an autonomic protection mechanism and gradually enhanced barrier properties during prolonged service.Our results provide a new venue for the design of stimuli-responsive smart materials characteristic of an open biological system and may serve as the basis for creating highly intelligent devices with sophisticated functionality.

关键词： biomimetics self-strengthening selfhealing smart coating epidermis-like

超快冷工艺制备的超高强度马氏体钢的显微组织和性能

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金属热处理 2024年第2期49卷 32-39页

作者：刘自权栗克建张龙柱李守华冯毅曹鹏军河钢集团邯钢公司技术中心河北邯郸056015 重庆科技大学冶金与材料工程学院重庆401331 中国汽车工程研究院股份有限公司重庆401122

利用超快冷工艺制备不同Mn添加量(1.01%、1.41%和1.74%,质量分数)的超高强度马氏体钢,采用XRD、SEM、EBSD、TEM等技术手段对比分析试验钢的原始奥氏体晶粒尺寸、高角度晶界比例、马氏体板条厚度和纳米析出相等显微组织差异,利用TDA技术... 详细信息

利用超快冷工艺制备不同Mn添加量(1.01%、1.41%和1.74%,质量分数)的超高强度马氏体钢,采用XRD、SEM、EBSD、TEM等技术手段对比分析试验钢的原始奥氏体晶粒尺寸、高角度晶界比例、马氏体板条厚度和纳米析出相等显微组织差异,利用TDA技术分析了钢的抗氢脆性能,同时利用第一性原理研究钢中Cu析出相界面处的氢陷阱。结果表明,随着Mn添加量的增加,1500 MPa级马氏体钢的原始奥氏体晶粒尺寸均约为7μm,但高Mn试样的马氏体板条更细、更密。第一性原理计算证明Cu与马氏体钢基体界面处可以形成良性氢陷阱,马氏体组织中大量的各类界面有助于在钢中形成更加分散的氢陷阱,氢在材料中就不容易局部聚集,从而降低材料氢脆断裂风险。基于超快冷工艺,Mn添加量增加可以实现1500 MPa级马氏体钢获得更多界面组织,微量的Cu析出也可以进一步提升材料的抗氢脆性能。

关键词：马氏体钢氢脆残留奥氏体氢陷阱第一性原理

Comparison of the boundary theory with the contact rule of phase regions and Gupta’s method

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Science China Chemistry 2006年第1期49卷 12-20页

作者： ZHAO Muyu WAN Qiang SONG Lizhu feng shouhua College of Chemistry Jilin University Changchun 130023 China College of Chemistry Jilin University Changchun 130023 China College of Chemistry Jilin University Changchun 130023 China College of Chemistry Jilin University Changchun 130023 China

The phase boundary theory and the contact rule of phase regions are compared, and some weaknesses of the latter are manifested. The comparison between the Gupta’s method and the boundary theory method for constructin... 详细信息

关键词： boundary theory, Palatnik-Landau's contact rule, Gupta's method, comparison.

Epitaxial thin film of SmFeO_3 ferroelectric heterostructures

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Science China Chemistry 2014年第6期57卷 803-806页

作者： SI WenZhe HUANG KeKe WU Xiaofeng feng shouhua State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin University

Epitaxial growth of SmFeO3/SrRuO3 was achieved on SrTiO3 substrates by the pulsed laser deposition(PLD)method at 973 K under oxygen partial pressure of 12.5 Pa.No Fe2+leakage was detected in our SmFeO3 film.The remanent polarization and coercive electric field of the thin film with a higher degree of orientation along(110)were 1.97μC/cm2 and 0.89×104 V/cm at room temperature,respectively.This film showed enhanced canted antiferromagnetism spin ordering compared with its corresponding powder materials.

关键词：外延薄膜异质铁电 SrRuO3 脉冲激光沉积 SrTiO3 外延生长剩余极化

Novel internal photoemission in manganite/ZnO heterostructure

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Science China Chemistry 2013年第5期56卷 583-587页

作者： ZHANG JiaQi HUANG KeKe SI WenZhe WU Xiaofeng CHENG Gang feng shouhua State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University

A novel photovoltaic phenomenon of internal photoemission was found in a low cost manganite La0.62Ca0.29K 0.09MnO3 (LCKMO)/zinc oxide (ZnO) heterojunction bilayers grown on ITO substrate by pulsed laser deposition (PLD) at relative low growth temperature. The heterostructure ITO/LCKMO/ZnO/Al exhibits reproducible rectifying characteristics and light current under continuous laser irradiation of = 325 nm. We report here the influence of LCKMO/ZnO bilayers' thickness on the electrical and photoelectric properties of the heterostructure at room temperature. The power conversion efficiency (PCE) is achieved when the LCKMO and ZnO layers are thin enough or the full space charge layer is sufficient. We obtained the maximum value of PCE of 0.0145% when the thicknesses of LCKMO and ZnO layers are 25 and 150 nm, respectively. The open circuit voltage is 0.04 V under this condition due to the internal photoemission.

关键词：异质结氧化锌脉冲激光沉积功率转换效率生长温度空间电荷层 ZnO 整流特性

Hydrothermal Synthesized Co-Ni3S2 Ultrathin Nanosheets for Efficient and Enhanced Overall Water Splitting

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Chemical Research in Chinese Universities 2019年第2期35卷 179-185页

作者： JIAN Juan YUAN Long LI He LIU Huanhuan ZHANG Xinghui SUN Xuejiao YUAN Hongming feng shouhua State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012P.R.China Key Laboratory of Functional Materials Physics and Chemistry Ministry of EducationJilin Normal UniversitySiping 136000R R. China

We used the one-step hydrothennal controlled synthesis method for Co-Ni3S2 ultrathin nanosheets grown directly on nickel foam(NF).The as-synthesized Co-Ni3S2/NF showed eiilianced activities in the hydrogen evolution reaction(HER),oxygen evolution reaction(OER)and better overall water splitting(OWS)efficiency than the iin-doped Ni3S2/NF.the voltage of Co-Ni3S2/NF for OWS was only 1.58 V at the current density of 10 niA/cm^2 and with long time(>30 h)current output during the current-density(i-t)test.The good i-t pertonnance was also observed in both HER and OER processes.Additionally,the Co-Ni3S2/NF showed a large current density(>1A/cm^2)for both HER and OER.Wlien the current densities reached 100 and 1000 mA/cm^2,the required overpotentials tor Co-Ni3S2/NF were 0.35 and 0.75 V for OER and 0.30 and 0.85 V for HER.Therefore,after introducing Co,the activity of Ni3S2-based material was strongly enhanced.

关键词： Co-Ni3S2/nickel tbam(NF) Ultrathin nanosheet Water splitting Hydrogen evolution reaction Oxygen evolution reaction