RT Journal Article ID 039bf09c545e3b2b A1 Gao, Tao A1 Jelle, Bjørn Petter A1 Sandberg, Linn Ingunn C. A1 Gustavsen, Arild T1 THERMAL CONDUCTIVITY OF MONODISPERSE SILICA NANOSPHERES JF Journal of Porous Media JO JPM YR 2015 FD 2015-11-06 VO 18 IS 10 SP 941 OP 947 K1 porous media K1 thermal insulation K1 nanosphere K1 silica AB Monodisperse hollow silica nanospheres (HSNSs) with an outer diameter of ~300 nm and shell thickness of ~50 nm were prepared via a spontaneous dissolution−regrowth process of solid silica nanospheres (SSNSs) in NaBH4 aqueous solution. Experimental results indicated that the as-prepared HSNSs have a reduced thermal conductivity of about 0.0519±0.0007 W/(m·K), compared to ~0.082±0.005 W/(m·K) of the corresponding SSNSs. Moreover, a small shell thickness and a small inner pore diameter are, in general, required to achieve HSNSs with low thermal conductivities. A comparison between HSNSs and SSNSs enables calculating the intrinsic solid thermal conductivity of SSNSs, which is about 0.042 W/(m·K) for SSNSs with a mean diameter of 200 nm. PB Begell House LK https://www.dl.begellhouse.com/journals/49dcde6d4c0809db,28ea5b261e5e33bf,039bf09c545e3b2b.html