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The characteristics of large surface area, high conductivity and mechanical flexibility performances make graphene suitable for high power next-generation energy storage devices. However, it only stores charge through double-layer capacitors, which limits its energy storage mechanism, resulting in a limited specific capacitance of graphene. In this paper, black Ti3+ self-doped nano titanium dioxide rods (TiOxNRs) were introduced into graphene nanosheets to improve capacitor performance. The results manifest that when 20 wt% TiOxNRs were added into the TiOxNRs/rGO composite, the capacitance performance is the best and the specific capacitance value is 149.5 F g−1 at the scanning speed of 40 mV s−1. In addition, the specific capacitance of the electrode prepared with the TiOxNRs/rGO composite still maintains the original 89.57% after 2000 charge–discharge cycles and has a good cycle life at a current density of 1 A g−1. In short, the TiOxNRs/rGO composite is a prospect and potential material for supercapacitor electrodes in the future.

Intermetallic compounds are commonly used in semiconductor, shape memory materials, hydrogen storage materials and magnetic materials due to their unique physical and chemical properties. In this study, the FeNi3/rGO (rGO: reduced graphene oxide) composite was prepared by one-step hydrothermal method using water-soluble nickel and iron salts as metal sources and hydrazine hydrate as reducing agent in alkaline solution. The structure of the composites are characterized by XRD, FTIR, XPS and Raman spectroscopy. The micromorphology of the samples is observed by SEM and TEM. The electrochemical performance of the FeNi3/rGO composite is evaluated by electrochemical impedance spectroscopy (EIS), galvanostatic charge–discharge (GCD) and cyclic voltammetry (CV). The results indicate that when the scan rate is 10 mV s−1 in 4 M KOH electrolyte solution, the specific capacitance of the FeNi3/rGO composite is 169.42 F g−1. At a current density of 1 A g−1, the specific capacitance of the FeNi3/rGO composite remains 82.72% of the original energy after 3000 cycles. Therefore, the FeNi3/rGO composite has excellent capacitance performance and is expected to be applied in supercapacitors and nanodevices in the future.

High performance and low process cost are two contradictory issues, which limited the commercial application of Li4Ti5O12 (LTO). Here, defects and TiO2 co-enhanced LTO have been synthesized by a simple solid-state method. The crystal structure and morphology of the as-synthesized samples were characterized. The results show that the uniform nanoparticles with spinel structure contained defects and TiO2. Defects and TiO2 co-enhanced LTO shows outstanding reversible discharge capacity of 168.2 mAh g−1 at 1 C after 500 cycles. Further, it presents a stability discharge ability of 155 mAh g−1 at 55 °C at 1 C after 500 cycles. The advanced electrochemical performance could be attributed to the defects and TiO2 in LTO, which enhance conductivity and produce rich reaction interface, facilitating Li+ ion diffusion kinetics. The as-synthesized LTO shows high performance in conjunction with low process cost.

We report on the development of a new type of nanoscale Cu2O hexapods with high H2S gas-sensing responsivity under low work temperature with engineering porous architectures through a rational synthesis design. The developed Cu2O hexapods show porous structure with outer diameters of 1–2 μm and the rodlike particles with mesoporous of 5–8 nm that constructed through the nanocrystals of 5–10 nm. The sensor based on porous Cu2O hexapods were synthesized and researched for the H2S-sensing properties. The response is 8.93 for the porous Cu2O hexapods, corresponding to the operating temperature 160 °C. By comparison, the response of the porous Cu2O hexapods is higher than the Cu2O hexapod during the detection range from 5 to 5000 ppm. The porous architecture could offer abundant active sites that promote the diffusion and adsorption procedure of the gas molecules. Furthermore, the response of porous Cu2O hexapods to 50 ppm H2S is 10.2 MΩ, the response time (τres) is within 0.11 s, and the recovery time (τrecov) is 31.0 s. Hence, using porous Cu2O hexapods architecture is beneficial to improve gas response, decrease the work temperature and shorten response time process.

A hierarchical micro flower structure NiCo2O4/GN/Fe3O4 composite was prepared with a two-step method. Then Fe3O4 nanoparticles were dressed up on petals of NiCo2O4/GN/Fe3O4 composite. It was successfully detected by instruments to analysis crystal texture, surface elements, micro morphology, magnetic properties and weight loss. Results showed that good synergistic effect of dielectric loss and magnetic loss of NiCo2O4/GN and Fe3O4 led to superior EM wave absorption. The minimum RL was − 38.18 dB at 10.6 GHz and effective absorption bandwidth

In the study, two kinds of nanomaterials [hexagonal nitride nanopowder (hBN) and graphene nanosheets (GNs)] were chosen as resin fillers due to their similar structures and excellent thermal properties. The hBN/CE, GNs/CE and hBN/GNs/CE resin nanocomposites with different hBN and/or GNs contents were prepared by a solution blended method. The structures of hBN and GNs, thermal and electrical conductivities, and thermal properties of the hBN/CE, GNs/CE and hBN/GNs/CE resin nanocomposites were observed with different test instruments. The results showed that the hBN had an analogous structure with GNs. The addition of hBN and GNs in the CE resin made the fractural surfaces of the resin nanocomposites rougher and more fold than that of the pure CE resin. For thermal conductivity, the synergistic effect of the hBN and GNs in the CE resin nanocomposites was better than the hBN or GNs filling the CE resin alone. The thermal diffusivity of GNs was good, meanwhile, the electrical conductivity of GNs was excellent as well. It indicated that the electrical conductivity of the GNs/CE resin nanocomposites was higher than that of the hBN/GNs/CE resin nanocomposites at a given volume contents. The data calculated from the TGA test was roughly corresponding to the experimental hBN and GNs volume content of the hBN/GNs/CE resin nanocomposites.

In this paper, a novel functional reduced graphene oxide (F-RGO) material was synthesized via the reduced graphene oxide graft with a silane coupling agent. Then, the functional reduced graphene oxide/bisphenol A cyanate ester (F-RGO/CE) nanocomposites were prepared with a solution intercalation method. The results showed that the F-RGO played a role of catalyst at the curing process of the F-RGO/CE nanocomposites. The optimal F-RGO nanosheets (3 wt%) improved the mechanical properties and the maximum values of the mechanical properties were impact strength 15.334 kJ/m2, flexural strength 104.68 MPa, tensile strength 9.3 MPa, modulus 2041.6 MPa and the elongation break values 5.5 mm for the F-RGO/CE nanocomposites, respectively. The Tg, Tc, crystallinity and densities of the F-RGO/CE nanocomposites were slightly decreased compared with the pure CE resin, respectively. And the addition of F-RGO slightly increased the thermal properties of the pure CE resin.