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Based on practical application requirements, the Cu alloy matrix with precipitates, particularly obstructing dislocation gliding, offers a promising pathway to substantially increase the strength of composites. Unfortunately, the fabrication of nano-precipitates often brings about extensive interface, which typically limits the electronic transmission capability and deteriorates the electrical conductivity. Herein, in-situ synthesized graphene nanoplatelets combined ball milling is deliberately selected to enable robust interfacial bonding and construct analogy-bicontinuous structures through hindering the diffusion of Ag in the Cu–Ag alloy matrix by the graphene nanoplatelets. The Cu alloy matrix composite after heat treatment exhibits a yield strength of ∼445 MPa and a fracture elongation of ∼13.5%, which is mainly ascribed to the introduction of the graphene nanoplatelets and the Ag nano-precipitates, and the adjustment of the analogy-bicontinuous structures. Meanwhile, the toughening mechanism of the Cu alloy matrix composite is rationalized on basis of delocalization and crack deflection affected by the graphene nanoplatelets and analogy-bicontinuous structures. Furthermore, the construction of continuous conductive path in the analogy-bicontinuous structures, refraining from the adverse effects caused by interface scattering, is of great benefit to the electrical conductivity, which is elevated to a high level of 92.2 IACS%. The present discoveries shed new insights into the innovative design of the Cu alloy matrix composites for advanced engineering applications by regulating the heterostructure. [Display omitted] • Analogy-bicontinuous structure was in situ synthesized with ball milling. • GNPs regulated the distribution of Ag nano-precipitates and electrical conductivity. • Synergy of mechanical properties and electrical conductivity was achieved. [ABSTRACT FROM AUTHOR]

Abstract: Uniform and small Fe3O4 nanocrystals (∼9nm) encapsulated in interconnected carbon nanospheres (∼60nm) for a high-rate Li-ion battery anode have been fabricated by a one-step hydrothermal process followed by annealing under Ar, which can be applied for the preparation of a number of metal oxide nanocrystals encapsulated in interconnected carbon nanospheres. The as-synthesized interconnected Fe3O4@C nanospheres displayed high performance as an anode material for Li-ion battery, such as high reversible lithium storage capacity (784mAh/g at 1 C after 50 cycles), high Coulombic efficiency (∼99%), excellent cycling stability, and superior rate capability (568mAh/g at 5 C and 379mAh/g at 10 C) by virtue of their unique structure: the nanosized Fe3O4 nanocrystals encapsulated in interconnected conductive carbon nanospheres not only endow large quantity of accessible active sites for lithium ion insertion as well as good conductivity and short diffusion length for lithium ion transport but also can effectively circumvent the volume expansion/contraction associated with lithium insertion/extraction. [Copyright &y& Elsevier]

Abstract: Two kinds of TiO2 with novel structures, interpenetrating anatase TiO2 tablets (IP-TiO2), and overlapping anatase TiO2 nanosheets (OL-TiO2) with exposed {001} facets, are synthesized. The graphene oxide (GO) supported ultrathin TiO2 nanosheets (OL-TiO2/GO) is also prepared by one-pot hydrothermal method. The microscopic feature, morphology, phase, and nitrogen adsorption–desorption isotherms are characterized. The performance of photocatalytic degradation of methyl blue is also measured. Compared with IP-TiO2, the OL-TiO2 with GO possess higher photocatalytic efficiency. The GO can improve the photocatalytic property by increasing specific surface area, accelerating the separation of electron–hole pairs, as well as extending the electron life. The growth process of TiO2 nanosheets on graphene oxide layers probably follows a step-growth mechanism with F− as morphology controlling agent. The steps on the surface can improve the photocatalytic activity further due to the increase of dangling bonds of 5-coordinated Ti (Ti5c) which are considered to be the active sites in the photocatalytic reaction. [Copyright &y& Elsevier]