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An ex situ strategy for fabrication of graphene oxide (GO)/metal oxide hybrids without assistance of surfactant is introduced. Guided by this strategy, GO/Al2O3 hybrids are fabricated by two kinds of titration methods in which GO and Al2O3 colloids are utilized as titrant for hybrids of low and high GO content respectively. After sintered by spark plasma sintering, few‐layer graphene (FG)/Al2O3 nanocomposites are obtained and GO is well reduced to FG simultaneously. A percolation threshold as low as 0.38 vol.% is achieved and the electrical conductivity surpasses 103 Sm−1 when FG content is only 2.35 vol.% in FG/Al2O3 composite, revealing the homogeneous dispersion and high quality of as‐prepared FG. Furthermore, it is found that the charge carrier type changes from p‐ to n‐type as graphene content becomes higher. It is deduced that this conversion is related to the doping effect induced by Al2O3 matrix and is thickness‐dependent with respect to FG.

Strong intergraphene shear resistance is engineered in multi‐walled carbon nanotubes (MWCNTs) by embedding the nanotubes into a compressive‐stressing ceramic environment to exploit the exceptional strength of its inner graphene walls during tensile loading. A dramatic enhancement in the tensile failure load of MWCNT is achieved in the ceramic environment and a new “multi‐wall” failure mechanism is discovered.

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