Designing a novel, efficient, and cost-effective nanostructure with the advantage of robust morphology and outstanding conductivity is highly promising for the electrode materials of high-performance electrochemical storage device. In this paper, a series of honeycombed perovskite-type Sr-doped LaNiO₃ nanosheets with abundant porous structure were successfully synthesized by accurately controlling the Sr-doped content. The study showed that the optimal LSNO-0.4 (La_0.6Sr_0.4NiO_3-δ) electrode exhibited excellent electrochemical performance, which showed a high capacity of 115.88 mAh g⁻¹ at 0.6 A g⁻¹. Furthermore, a hybrid supercapacitor device (LSNO//AC) based on LSNO-0.4 composites and activated carbon (AC) showed a high energy density of 17.94 W h kg⁻¹, a high power density of 1600 W kg⁻¹, and an outstanding long-term stability with 104.4% capacity retention after 16,000 cycles, showing an excellent electrochemical performance and a promising application as an electrode for energy storage.

The thermoelectric refrigeration system is an application of the Peltier effect, and good refrigeration performance is dependent on effective heat dissipation performance. To enhance the cooling performance of the thermoelectric system, this paper designs a new type of finned heat sink, which does not change the overall size of the thermoelectric system. The performance of the refrigeration system under the new fin is tested by experiments under various conditions. During the experiment, the cooling wind speed, the temperature of the hot and cold side of the TEC, the power consumption of the fan, and other parameters were directly recorded through the measuring instrument. The results show that the use of new finned heat sinks can improve the COP of the thermoelectric refrigeration system. Within the scope of the study, the thermal resistance of the new fins can be reduced by 42.6%, and the system COP value can be increased by 22.8%. In addition, increasing the cooling wind speed can further reduce the cold side temperature. Within the research range, the lowest temperature can reach −8.25 °C, but the power consumed by the fan is 166% of that of the conventional fin heat sink refrigeration device.

Thermocompression bonding of copper to copper using copper nanoparticles is studied using molecular dynamics. The bonding interface formation process is investigated frst. For the bonding process, the effects of temperature and external pressure are examined. Also, we examine the grain growth at the interface. The results show that the nanoparticles with high surface energy and low compressive strength provide the active atoms to bond with copper. Pressure determining the degree of deformation of nanoparticles transfers atoms from the interior to the surface of nanoparticles and provide more surface atom to form bonds with bulk copper. While continuous pressure increase does not help bonding, higher temperature will facilitate formation of vacancies by breaking the bonds and driving the metal atoms into these vacancies. In addition, a higher temperature promotes grain growth at the interface. These behaviors indicate that using nanoparticles as a bonding layer in metal bonding can effectively reduce bonding temperature and pressure. It is necessary to select appropriate pressure at initial bonding stage and provide continuous high-temperature hold time.

Graphene-copper nanolayered composites have received research interest as promising packaging materials in developing next-generation electronic and optoelectronic devices. The weak van der Waal (vdW) contact between graphene and metal matrix significantly reduces the mechanical performance of such composites. The current study describes a new Cu-nanoporous graphene-Cu based bonding method with a low bonding temperature and good dependability. The deposition of copper atoms onto nanoporous graphene can help to generate nanoislands on the graphene surface, facilitating atomic diffusion bonding to bulk copper bonding surfaces at low temperatures, according to our extensive molecular dynamics (MD) simulations on the bonding process and pull-out verification using the canonical ensemble (NVT). Furthermore, the interfacial mechanical characteristics of graphene/Cu nanocomposites can be greatly improved by the resistance of nanostructure in nanoporous graphene. These findings are useful in designing advanced metallic surface bonding processes and graphene-based composites with tenable performance.

Surface bonding is an essential step in device manufacturing and assembly, providing mechanical support, heat transfer, and electrical integration. Molecular dynamics simulations of surface bonding and debonding failure of copper nanocones are conducted to investigate the underlying adhesive mechanism of nanocones and the effects of separation distance, contact length, temperature, and size of the cones. It is found that van der Waals interactions and surface atom diffusion simultaneously contribute to bonding strength, and different adhesive mechanisms play a main role in different regimes. The results reveal that increasing contact length and decreasing separation distance can simultaneously contribute to increasing bonding strength. Furthermore, our simulations indicate that a higher temperature promotes diffusion across the interface so that subsequent cooling results in better adhesion when compared with cold bonding at the same lower temperature. It also reveals that maximum bonding strength was obtained when the cone angle was around 53°. These findings are useful in designing advanced metallic bonding processes at low temperatures and pressure with tenable performance.