nl401308v_si_001.pdf (679.37 kB)
Ultralight Three-Dimensional Boron Nitride Foam with Ultralow Permittivity and Superelasticity
journal contribution
posted on 2013-07-10, 00:00 authored by Jun Yin, Xuemei Li, Jianxin Zhou, Wanlin GuoDielectrics
with ultralow permittivity within 2 times that of air,
excellent mechanical performance, and high thermal stability are highly
attractive to many applications. However, since the finding of silica
aerogels in the 1930s, no alternative ultralight porous dielectric
with density below 10 mg/cm3 has been developed. Here we
present three-dimensional hierarchical boron nitride foam with permittivity
of 1.03 times that of air, density of 1.6 mg/cm3, and thermal
stability up to 1200 °C obtained by chemical vapor deposition
on a nickel foam template. This BN foam exhibits complete recovery
after cyclic compression exceeding 70% with permittivity within 1.12
times that of air. Gathering all these exceptional characters, the
BN foam should create a breakthrough development of flexible ultralow-permittivity
dielectrics and ultralight materials.