Pham Thang, Goldstein Anna P, Lewicki James P, Kucheyev Sergei O, Wang Cheng, Russell Thomas P, Worsley Marcus A, Woo Leta, Mickelson William, Zettl Alex
Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA.
Nanoscale. 2015 Jun 21;7(23):10449-58. doi: 10.1039/c5nr01672j.
Aerogels have much potential in both research and industrial applications due to their high surface area, low density, and fine pore size distribution. Here we report a thorough structural study of three-dimensional aerogels composed of highly crystalline sp(2)-bonded boron nitride (BN) layers synthesized by a carbothermic reduction process. The structure, crystallinity and bonding of the as-prepared BN aerogels are elucidated by X-ray diffraction, (11)B nuclear magnetic resonance, transmission electron microscopy, and resonant soft X-ray scattering. The macroscopic roughness of the aerogel's surface causes it to be superhydrophobic with a contact angle of ∼155° and exhibit high oil uptake capacity (up to 1500 wt%). The oil can be removed from the BN aerogel by oxidizing in air without damaging the crystalline porous structure of the aerogel or diminishing its oil absorption capacity.
气凝胶因其高比表面积、低密度和精细的孔径分布，在研究和工业应用中都具有很大潜力。在此，我们报告了对通过碳热还原法合成的由高度结晶的sp(2)键合氮化硼（BN）层组成的三维气凝胶的全面结构研究。通过X射线衍射、(11)B核磁共振、透射电子显微镜和共振软X射线散射对所制备的BN气凝胶的结构、结晶度和键合进行了阐明。气凝胶表面的宏观粗糙度使其具有超疏水性，接触角约为155°，并表现出高吸油能力（高达1500 wt%）。通过在空气中氧化，可以从BN气凝胶中除去油，而不会破坏气凝胶的晶体多孔结构或降低其吸油能力。
