Agradecimentos: The authors acknowledge the funding support from the U.S. Air Force Office of Scientific Research (Award No. FA9550-14-1-0268 and Award No. FA9550-12-1-0035). C. Gautam and S. Jose acknowledge financial support from University Grants Commission, New Delhi, Government of India, for the Raman Fellowship. G. Brunetto and D. S. Galvao acknowledge financial support from the Brazilian Agencies CNPq, CAPES, and FAPESP and thank the Center for Computational Engineering and Sciences at Unicamp for financial support through the FAPESP/CEPID Grant 2013/08293-7 Ver menos

Abstract: Here, we report the scalable synthesis and characterization of low-density, porous, three-dimensional (3D) solids consisting of two-dimensional (2D) hexagonal boron nitride (h-BN) sheets. The structures are synthesized using bottom-up, low-temperature (similar to 300 degrees C), solid-state reaction of melamine and boric acid giving rise to porous and mechanically stable interconnected h-BN layers. A layered 3D structure forms due to the formation of h-BN, and significant improvements in the mechanical properties were observed over a range of temperatures, compared to graphene oxide or reduced graphene oxide foams. A theoretical model based on Density Functional Theory (DFT) is proposed for the formation of h-BN architectures. The material shows excellent, recyclable absorption capacity for oils and organic solvents Ver menos