A Facile Bonding Material to Enable Interconnection among complex Surfaces through AgNWs Aerogel

Metal aerogels are a new material class with unique properties, including lightweight, high surface area, high reactivity, and high electrical conductivity, making them highly attractive in various applications, such as sensing, thermal insulation, energy generation/storage, and catalytic conversion. A novel flexible preformed film has been produced from the AgNW aerogel to realize the flexible integration among complex structures in this work. As the AgNW forming bulk 3D networks in the aerogel has excellent flexibility, stability and high reactivity and conductivity, the proposed preformed film can enable the interconnection between metals like Cu or Ag through self-sintering without additional flux or solders. According to the experimental data, reliable and flux-free bonds can be achieved between components with If-shaped, V-shaped, round-shaped or step-shaped structures through the preformed AgNW aerogel film, with a high shear strength over 30 MPa, a low electrical resistivity less than 4.5 J.1g.cm and a large thermal conductivity attaining 110 W/m*K, if proper temperature and stress were applied. Meanwhile, these flexible preformed films can also provide ultra-high electromagnetic shielding effect over 75 dB in the frequency range of 8-12 GHz, and be further combined with PDMS to serve as a flexible circuit with a high electrical conductivity over 1.4*106 S/m. In summary, this work provides novel approaches to realize the adaptive interconnection between complex structures and provide new material classes for electromagnetic shielding and flexible circuit, which may enable the extended usage of metal aerogel materials in flexible electronics and packaging.