A novel method was developed to promote the multifunctional applications of chemically reduced graphene (rGE) in silicone elastomers (SE) and polyaniline (PANI)-based supercapacitors via the integration of SiO2. With the help of SiO2, the surface status of rGE can be designed according to actual needs and the generated rGE–SiO2 (rGES) showed various microstructures including lamellar, dendritic and sandwich-like shapes. The microstructures of rGES played a decisive role in the final functions of rGES-based polymer nanocomposites, which were better than the rGE-based polymer matrixes. Generally, lamellar rGES retained and stimulated the advantages of rGE, and the rGES-integrated PANI electrode (rGESP) showed better specific capacitance (555 F g−1) and cycling life (91%) than the rGE-integrated PANI electrode (381 F g−1 and 79%). Sandwich-like rGES promoted the mechanical performances of SE, and the values of rGES/SE (rGESSE) are ten times higher than those of rGE/SE, from 0.4 MPa to more than 7 MPa for the tensile strength and from 0.28 MPa to 3.7 MPa for the tensile modulus. Thus, the fabricated rGES is smart and designable, displaying multiple functions and applications.

Interfacial interaction between graphene oxide (GEO) sheets and polysiloxane is important for the applications of GEO based silicone systems. However, polysiloxane is a polymer that suffers from poor affinity with graphene oxide, which has become a bottleneck for the integration and applications of GEO in such polymer matrixes. Here we introduce an effective approach to solve the problem by employing SiO2 as an interfacial layer. Being compatible with both GEO and silicone, the interfacial layer is nanoporous and tunable. Firstly, GEO was modified with nanoporous SiO2 via a sol–gel process. Secondly, GEO/SiO2 (GEOS) was integrated into a fluid-like hydroxyl terminated polydimethylsiloxane (PDMS-OH) through a solvent-free blending process. Thirdly, the GEOS/PDMS-OH matrix was vulcanized at room temperature (RTV), forming the final silicon rubber (SR) elastomer. A tensile strength of 3.36 MPa and a Young's modulus of 3.38 MPa were achieved for the RTV SR elastomer, higher than those of GEO (0.69 and 1.40 MPa) and fumed SiO2 (1.32 and 2.2 MPa) based ones at the same filling fractions. The strong interactions between SiO2 and GEO, as well as excellent compatibility between SiO2 and PDMS-OH, make SiO2 act as a bridge for stress transmission between GEO and PDMS-OH. Simultaneously, the adjustable nanoporous architecture at the GEO/PDMS-OH interface was demonstrated to be an important contributing factor for enhanced stress transmission and mechanical properties.