In this article Florian Puchtler at affiliation‘University of Bayreuth’,Josef Breu at affiliation‘University of Bayreuth’,and Ziliang Wu at affiliation‘Zhejiang University’was missing from the author Min Cao,Sen...In this article Florian Puchtler at affiliation‘University of Bayreuth’,Josef Breu at affiliation‘University of Bayreuth’,and Ziliang Wu at affiliation‘Zhejiang University’was missing from the author Min Cao,Senping Liu,Qingli Zhu,Ya Wang,Jingyu Ma,Zeshen Li,Dan Chang,Enhui Zhu,Xin Ming,Florian Puchtler,Josef Breu,Ziliang Wu,Yingjun Liu,Yanqiu Jiang,Zhen Xu,Chao Gao list.展开更多
Eliminating topological defects to achieve monodomain liquid crystals is highly significant for the fundamental studies of soft matter and building long-range ordered materials.However,liquid crystals are metastable a...Eliminating topological defects to achieve monodomain liquid crystals is highly significant for the fundamental studies of soft matter and building long-range ordered materials.However,liquid crystals are metastable and sensitive to external stimuli,such as flow,confinement,and electromagnetic fields,which cause their intrinsic polycrystallinity and topological defects.Here,we achieve the monodomain liquid crystals of graphene oxide over 30 cm through boundary-free sheargraphy.The obtained monodomain liquid crystals exhibit large-area uniform alignment of sheets,which has the same optical polarized angle and intensity.The monodomain liquid crystals provide bidirectionally ordered skeletons,which can be applied as lightweight thermal management materials with bidirectionally high thermal and electrical conductivity.Furthermore,we extend the controllable topology of two-dimensional colloids by introducing singularities and disclinations in monodomain liquid crystals.Topological structures with defect strength from−2 to+2 were realized.This work provides a facile methodology to study the structural order of soft matter at a macroscopic level,facilitating the fabrication of metamaterials with tunable and highly anisotropic architectures.展开更多
The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different ...The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different from usual polymers and metals,graphene solids exhibit limited deformability and processibility for precise forming.Here,we present a precise thermoplastic forming of graphene materials by polymer intercalation from graphene oxide(GO)precursor.The intercalated polymer enables the thermoplasticity of GO solids by thermally activated motion of polymer chains.We detect a critical minimum containing of intercalated polymer that can expand the interlayer spacing exceeding 1.4 nm to activate thermoplasticity,which becomes the criteria for thermal plastic forming of GO solids.By thermoplastic forming,the flat GO-composite films are forged to Gaussian curved shapes and imprinted to have surface relief patterns with size precision down to 360 nm.The plastic-formed structures maintain the structural integration with outstanding electrical(3.07×10^(5) S m^(−1))and thermal conductivity(745.65 W m^(−1) K^(−1))after removal of polymers.The thermoplastic strategy greatly extends the forming capability of GO materials and other layered materials and promises versatile structural designs for more broad applications.展开更多
石墨烯气凝胶(GAs)在解决下一代电子器件电磁屏蔽污染方面引起了广泛关注.但是,由于超轻石墨烯气凝胶在复杂环境中结构不稳定,其在电磁屏蔽的实际应用中仍面临巨大的挑战.在此,我们提出一类机械结构稳定的石墨烯气凝胶,其展示出优异可...石墨烯气凝胶(GAs)在解决下一代电子器件电磁屏蔽污染方面引起了广泛关注.但是,由于超轻石墨烯气凝胶在复杂环境中结构不稳定,其在电磁屏蔽的实际应用中仍面临巨大的挑战.在此,我们提出一类机械结构稳定的石墨烯气凝胶,其展示出优异可靠的电磁屏蔽性能.这类气凝胶呈现出面面堆叠的结构,在密度ρ=3.7 mg cm-3,高度1 m m时,电磁屏蔽效能可达到64.1 d B,比电磁屏蔽效能达到173,243 dB cm2g-1,远超现有报道的碳基材料.同时,石墨烯气凝胶具有优异的环境适应性,在机械形变、极端温度、燃烧及水下等环境中均可保持性能稳定.此外,制备的石墨烯气凝胶可通过真空袋装工艺进行包装运输,解决了超轻材料实际应用中低密度与大体积的矛盾,且在这一极端变形过程中材料结构和性能均未产生破坏.该研究为石墨烯气凝胶电磁屏蔽材料的实际应用铺平了道路,且拓展了其实际应用场景,比如航天、军事战机及海洋领域.展开更多
Macroscopic assembly of graphene sheets has renovated the preparation of neat carbonaceous fbers with integrating high performance and superior functionalities,beyond the pyrolysis of conventional polymeric precursors...Macroscopic assembly of graphene sheets has renovated the preparation of neat carbonaceous fbers with integrating high performance and superior functionalities,beyond the pyrolysis of conventional polymeric precursors.To date,graphene microfbers by the liquid crystalline wet-spinning method have been established.However,how to reliably prepare continuous neat graphene nanofbers remains unknown.Here,we present the electrospinning of neat graphene nanofbers enabled by modulating colossally extensional fow state of graphene oxide liquid crystals.We use polymer with mega molecular weight as transient additives to realize the colossal extensional fow and electrospinning.The neat graphene nanofbers feature high electronic quality and crystallinity and exhibit high electrical conductivity of 2.02×10^(6) S/m that is to be comparable with single crystal graphite whisker.The electrospinning of graphene nanofbers was extended to prepare large-area fabric with high fexibility and superior specifc electrical/thermal conductivities.The electrospinning of graphene nanofbers opens the door to nanofbers of rich two-dimensional sheets and the neat graphene nanofbers may grow to be a new species after conventional carbonaceous nanofbers and whiskers in broad functional applications.展开更多
文摘In this article Florian Puchtler at affiliation‘University of Bayreuth’,Josef Breu at affiliation‘University of Bayreuth’,and Ziliang Wu at affiliation‘Zhejiang University’was missing from the author Min Cao,Senping Liu,Qingli Zhu,Ya Wang,Jingyu Ma,Zeshen Li,Dan Chang,Enhui Zhu,Xin Ming,Florian Puchtler,Josef Breu,Ziliang Wu,Yingjun Liu,Yanqiu Jiang,Zhen Xu,Chao Gao list.
基金The authors gratefully acknowledge the support of National Key Research and Development Program of China(2020YFE0204400)National Natural Science Foundation of China(Nos.52090030,52122301,51973191)+3 种基金Shanxi-Zheda Institute of New Materials and Chemical Engineering(2012SZ-FR004)Hundred Talents Program of Zhejiang University(188020*194231701/113)China Postdoctoral Science Foundation(2021M692772)supported by the Fundamental Research Funds for the Central Universities(Nos.2021FZZX001-17).
文摘Eliminating topological defects to achieve monodomain liquid crystals is highly significant for the fundamental studies of soft matter and building long-range ordered materials.However,liquid crystals are metastable and sensitive to external stimuli,such as flow,confinement,and electromagnetic fields,which cause their intrinsic polycrystallinity and topological defects.Here,we achieve the monodomain liquid crystals of graphene oxide over 30 cm through boundary-free sheargraphy.The obtained monodomain liquid crystals exhibit large-area uniform alignment of sheets,which has the same optical polarized angle and intensity.The monodomain liquid crystals provide bidirectionally ordered skeletons,which can be applied as lightweight thermal management materials with bidirectionally high thermal and electrical conductivity.Furthermore,we extend the controllable topology of two-dimensional colloids by introducing singularities and disclinations in monodomain liquid crystals.Topological structures with defect strength from−2 to+2 were realized.This work provides a facile methodology to study the structural order of soft matter at a macroscopic level,facilitating the fabrication of metamaterials with tunable and highly anisotropic architectures.
基金the support of the National Natural Science Foundation of China(Nos.51803177,51973191,51533008,and 51636002)National Key R&D Program of China(No.2016YFA0200200)+5 种基金the China Postdoctoral Science Foundation(No.2021M690134)Hundred Talents Program of Zhejiang University(188020*194231701/113)Key Research and Development Plan of Zhejiang Province(2018C01049)the National Postdoctoral Program for Innovative Talents(No.BX201700209)the Fundamental Research Funds for the Central Universities(2021FZZX001-17),the Natural Science Foundation of Jiangsu Province(BK20210353)the Fundamental Research Funds for the Central Universities(No.30920041106).
文摘The processing capability is vital for the wide applications of materials to forge structures as-demand.Graphene-based macroscopic materials have shown excellent mechanical and functional properties.However,different from usual polymers and metals,graphene solids exhibit limited deformability and processibility for precise forming.Here,we present a precise thermoplastic forming of graphene materials by polymer intercalation from graphene oxide(GO)precursor.The intercalated polymer enables the thermoplasticity of GO solids by thermally activated motion of polymer chains.We detect a critical minimum containing of intercalated polymer that can expand the interlayer spacing exceeding 1.4 nm to activate thermoplasticity,which becomes the criteria for thermal plastic forming of GO solids.By thermoplastic forming,the flat GO-composite films are forged to Gaussian curved shapes and imprinted to have surface relief patterns with size precision down to 360 nm.The plastic-formed structures maintain the structural integration with outstanding electrical(3.07×10^(5) S m^(−1))and thermal conductivity(745.65 W m^(−1) K^(−1))after removal of polymers.The thermoplastic strategy greatly extends the forming capability of GO materials and other layered materials and promises versatile structural designs for more broad applications.
基金supported by the MOE Key Laboratory of Macromolecular Synthesis and Functionalization, the International Research Center for X Polymers, the National Natural Science Foundation of China (51973191, 52272046 and 52090030)Shanxi-Zheda Institute of New Materials and Chemical Engineering (2011SZ-FR004 and 2022SZ-TD011)+6 种基金the Hundred Talents Program of Zhejiang University (188020*194231701/ 113)Fujian Provincial Science and Technology Major Projects (2018HZ0001-2)the Fundamental Research Funds for the Central Universities (K20200060 and 2021FZZX001-17)the Key Laboratory of Novel Adsorption and Separation Materials and Application Technology of Zhejiang Province (512301-I21502)China Postdoctoral Science Foundation (2021M702788)the Postdoctoral Research Program of Zhejiang Province (ZJ2021145)the Devices of the Ministry of Education NJ2020003 (INMD-2021M06)。
文摘石墨烯气凝胶(GAs)在解决下一代电子器件电磁屏蔽污染方面引起了广泛关注.但是,由于超轻石墨烯气凝胶在复杂环境中结构不稳定,其在电磁屏蔽的实际应用中仍面临巨大的挑战.在此,我们提出一类机械结构稳定的石墨烯气凝胶,其展示出优异可靠的电磁屏蔽性能.这类气凝胶呈现出面面堆叠的结构,在密度ρ=3.7 mg cm-3,高度1 m m时,电磁屏蔽效能可达到64.1 d B,比电磁屏蔽效能达到173,243 dB cm2g-1,远超现有报道的碳基材料.同时,石墨烯气凝胶具有优异的环境适应性,在机械形变、极端温度、燃烧及水下等环境中均可保持性能稳定.此外,制备的石墨烯气凝胶可通过真空袋装工艺进行包装运输,解决了超轻材料实际应用中低密度与大体积的矛盾,且在这一极端变形过程中材料结构和性能均未产生破坏.该研究为石墨烯气凝胶电磁屏蔽材料的实际应用铺平了道路,且拓展了其实际应用场景,比如航天、军事战机及海洋领域.
基金This work is supported by the National Natural Science Foundation of China(Nos.52090030,51973191,51533008,51803177 and 51873191)Hundred Talents Program of Zhejiang University(188020*194231701/113)+7 种基金National Key R&D Program of China(No.2016YFA0200200)Key research and development plan of Zhejiang Province(2018C01049)Fujian Provincial Science and Technology Major Projects(NO.2018HZ0001-2)the Fundamental Research Funds for the Central Universities(NO.K20200060)Key Laboratory of Novel Adsorption and Separation Materials and Application Technology of Zhejiang Province(512301-I21502)Shandong Provincial Natural Science Foundation(ZR2019YQ19)Project of Shandong Province Higher Educational Science and Technology Program(2019KJA026)State Key Laboratory for Modifcation of Chemical Fibers and Polymer Materials,Donghua University(KF2110).
文摘Macroscopic assembly of graphene sheets has renovated the preparation of neat carbonaceous fbers with integrating high performance and superior functionalities,beyond the pyrolysis of conventional polymeric precursors.To date,graphene microfbers by the liquid crystalline wet-spinning method have been established.However,how to reliably prepare continuous neat graphene nanofbers remains unknown.Here,we present the electrospinning of neat graphene nanofbers enabled by modulating colossally extensional fow state of graphene oxide liquid crystals.We use polymer with mega molecular weight as transient additives to realize the colossal extensional fow and electrospinning.The neat graphene nanofbers feature high electronic quality and crystallinity and exhibit high electrical conductivity of 2.02×10^(6) S/m that is to be comparable with single crystal graphite whisker.The electrospinning of graphene nanofbers was extended to prepare large-area fabric with high fexibility and superior specifc electrical/thermal conductivities.The electrospinning of graphene nanofbers opens the door to nanofbers of rich two-dimensional sheets and the neat graphene nanofbers may grow to be a new species after conventional carbonaceous nanofbers and whiskers in broad functional applications.