Hexagonal boron nitride hollow capsules with collapsed surfaces: Chemical vapor deposition with single-source precursor ammonium fluoroborate

SBA-15 (mesoporous SiO₂) is used to stabilize and transfer F^- in the NH₄BF₄ CVD reaction for the first time, and a large-scale crystalline h-BN phase can be prepared. We successfully fabricate hollow h-BN capsules with collapsed surfaces in our designed NH₄BF₄ CVD system. Optimum temperature conditions are obtained, and a detailed formation mechanism is further proposed. The successful SBA-15-assisted NH₄BF₄ CVD route is of importance and enriches the engineering technology in the h-BN single-source CVD reaction.