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The structural instability of metal oxides retards realizing high-performance and long lifespan supercapacitors. We prepare an electrochemical active heterostructure of NiCo layered double hydroxide (LDH) confined by carboxyl carbon nanotube (CNTCOOH). Through the electrostatic interactions between carboxyl groups (COO−) of CNTCOOH and metal cations of LDH under a simple hydrothermal treatment, the CNTCOOH confined NiCoLDH (CNTCOOH- c -NiCoLDH) can be easily fabricated. The CNTCOOH- c -NiCoLDH demonstrates the specific morphology of rope-fastened plates and shows ultrahigh cycled stability. In addition, the hydrophilic carboxyl groups on CNTCOOH also regulates the interfacial electronic coupling and electrolyte soaking, resulting in high rate capability. The charge-storage capacitance of CNTCOOH- c -NiCoLDH heterostructures reaches 2120.8 F/g at 1 A/g. The devices of CNTCOOH- c -NiCoLDH//AC show both high energy density (171.0 Wh/kg) and high power density (950.0 W/kg), and have ultrahigh capacity retention rate of 93.64 % after 50,000 charge and discharge cycles at a high current density of 5 A/g. This work supports an effective confinement idea and a facile method that can be applied on a large scale for the design and fabrication of super high stable metal oxide-based supercapacitors. [Display omitted] • Through the strengthened interactions between carboxyl of CNTCOOH and metal cations of LDH, CNTCOOH-c-NiCoLDH is prepared. • The specific capacitance of CNTCOOH-c-NiCoLDH flowers reaches 2120.8 F/g at a current density of 1 A/g. • CNTCOOH-c-NiCoLDH//AC shows high capacity retention rate of 93.64 % after 50000 cycles at 5 A/g. [ABSTRACT FROM AUTHOR]

In this paper, the safe sealing temperature range of tempered glass was determined to be no more than 300 °C by experiments. On this basis, the feasibility of silver oxide system low melting solder (SOSLMS) used in tempered vacuum glazing (TVG) sealing was explored by sealing strength experiment, scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and other test methods. The results of sealing strength experiment showed that the bonding strength of the sealing layer was inversely proportional to the sealing temperature. The bonding strength of the sealing layer in the range of 260 °C–290 °C met the standard requirements (not less than 0.6 MPa) except for the failure of the sample sealing at 300 °C. The observation results of SEM showed that when the sealing temperature was 260 °C and 270 °C, the solder layer had uniform fusion and dense structure, and the sealing layer was tightly bonded. With the increase of sealing temperature, the solder layer began to produce large holes, and there was obvious open gap between solder layer and glass substrate after stretching. The analysis results of EDS showed that the Ag and V elements all diffused into the glass at each sealing temperature, the difference of diffusion concentration and distribution was not significant. The analysis results of XRD showed that when the sealing temperature was in the range of 260 °C–270 °C, there was no crystallization phenomenon in the SOSLMS. When the sealing temperature was in the range of 280 °C–300 °C, Ag 2 VO 2 PO 4 crystals began to precipitate, and with the increase of temperature, the higher the crystallinity was, the greater the crystal content was. In conclusion, in the range of 260 °C–270 °C, the SOSLMS showed good sealing performance, which was suitable for TVG sealing. • A kind of silver oxide system low melting solder was considered to be suitable for tempered vacuum glazing sealing. • The optimal sealing temperature range of silver oxide system low melting solder was 260 °C–270 °C. • The bonding strength of the sealing layer was inversely proportional to the sealing temperature. • The precipitation of Ag 2 VO 2 PO 4 crystals was considered to be the fundamental reason of the reduction of bonding strength. [ABSTRACT FROM AUTHOR]