Ionic liquid gel polymers have widely been used as the electrolytes in all-solid-state supercapacitors, but they suffer from low ionic conductivity and poor electrochemical performance. Arc discharge is a fast, low-cost and scalable method to prepare multi-layered graphene nanosheets, and as-made graphene nanosheets (denoted as ad-GNSs) with few defects, high electrical conductivity and high thermal stability should be favorable conductive additive materials. Here, a novel ionic liquid gel polymer electrolyte based on an ionic liquid (EMIMNTF2) and an copolymer (P(VDF-HFP)) was modified by the addition of ad-GNSs as an ionic conducting promoter. This modified gel electrolyte shows excellent thermal stability up to 400 °C and a wide electrochemical window of 3 V. An all-solid-state supercapacitor based on commercial activated carbon was fabricated using this modified ionic liquid gel polymer electrolyte, which shows obviously improved electrochemical behaviors compared with those of the corresponding all-solid-state supercapacitor using pure ionic liquid gel polymer electrolyte. Specially, smaller internal resistance, higher specific capacitance, better rate performance and cycling stability are achieved. These results indicate that the ionic liquid gel polymers modified by ad-GNSs would be promising and suitable gel electrolytes for high performance all-solid-state electrochemical devices.Several layer graphene nanosheets (ad-GNSs) were synthesized by the arc discharge method. Ionic liquid (IL) gel polymer electrolytes were modified by the addition of ad-GNSs as ionic conducting promoters, resulting in higher conductivity and better electrochemical performance than pure IL gel polymer electrolytes.

The effect of cooling rate on plastic deformation of Zr-based bulk metallic glasses has been studied. The specimens with the diameters of 3 mm, 4 mm and 6 mm cut from the same ladder-shaped Zr55Al10Ni5Cu30 BMG rod were used in the present investigation. The experimental results indicated that the different plastic strains were induced for the three type compression specimens. The compressive plastic strain increased with the decreasing diameter for the as-cast specimens, which means that the compressive plastic strain increased with the increasing cooling rate. The reason of the difference is attributed to the free volume existed in the BMGs during the rapid solidification, and the larger free volume was contained in the specimen fabricated with the higher cooling rate. It has been found that the prominent serrations and multiple shear bands appeared during the compressive deformation tests of the specimen with smaller diameter of 3 mm, indicating that the specimen with smaller diameter exhibits better plasticity due to more free volume content.

AbstractSeries of rod samples of Zr55Al10Ni5Cu30 alloy were prepared by magnetic suspend melting and copper mold suction casting method. The effect of thermal rate treatment (TRT) process on glass forming ability (GFA), mechanical properties and microstructure of Zr-based bulk metallic glass were investigated. It shows that GAF, mechanical properties and microstructure of as-cast Zr55Al10Ni5Cu30 BMGs alloy to a large extent is related to TRT process. GFA and thermal stability of as-cast Zr55Al10Ni5Cu30 alloy increase when overheating temperature increases. Supercooled liquid region ΔTx and parameter γ increase from 73 K to 89 K, from 0.413 to 0.417, respectively, when casting voltage increases from 7 kV to 10 kV. And a threshold overheating temperature is found for the fully amorphous structure, below which it may have an intersection with the crystallization position. It is found that the compressive strength increases and the compressive plasticity slightly decreases when overheating temperature increases. However, the compressive strength and the compressive plasticity simultaneously increase to 1.91 MPa and 2% when casting voltage increases to10 kV.

A pronounced effect of overheating is observed on the thermal stability and mechanical properties of Cu36Zr48Ag8Al8 bulk metallic glass. Higher overheated temperature enhances the thermal stability of bulk amorphous alloys, corresponding to higher specific-heat capacity and the smaller initial defect concentration. And a threshold overheating temperature is found for the fully amorphous structure. Bulk amorphous alloys exhibit good compressive plasticity at small overheat levels, whereas the compressive fracture strength and micro-hardness exhibit a significant increase first and then a slightly decrease. Mechanical properties of BMGs can be tailored in certain extent by controlling the overheated level, which is correlated with free volume and residual stresses.