Design of porous boron nitride materials for applications in adsorption

Porous boron nitride (BN) recently emerged as a new class of adsorbent material with bond polarity and unprecedented high thermal and oxidative stabilities. These properties make BN an attractive adsorbent for use in a wide range of adsorption applications, especially those operating under extreme conditions. Yet, the number of studies on this fascinating material remain limited and its structure and chemistry still vastly unknown. A full understanding of its formation mechanisms, as well as control of its pore structure and chemistry, are necessary to exploit its full potential. This thesis presents an in-depth investigation of the effects of synthesis conditions on the formation of porous BN and a detailed characterisation of the material. A novel synthesis method was developed for producing high surface area (>1900 m2/g) porous BN with tuneable micro- and mesoporosity, without the use of templates, presenting opportunity for scalability. The shaping of porous BN powders into industrially relevant pellet morphologies was achieved with no significant detriment to the desirable textural properties of the material. A way to reduce the hydrolytic instability of porous BN is elucidated and samples with significantly higher water tolerance were produced. Finally, porous BN materials with various pore structures and chemistries were tested for a range of adsorption applications in gas, liquid and vapour phase, identifying adsorption mechanisms and outlining potential ways to improve adsorption performance. Overall, this thesis opens the door to the design and improvement of porous BN, establishing it as a promising adsorbent material.Open Acces