Nickel (II) modified porous boron nitride : An effective adsorbent for tetracycline removal from aqueous solution

Contamination of aqueous environment caused by various antibiotics has attracted wide attention. It is important to find effective adsorbents for the removal of toxic compounds. Herein, Ni (II) was anchored at the surface of porous boron nitride (BN) by a facile way to enhance the adsorption performance for tetracycline (TC). The interaction between porous BN and Ni (II) was proved to be B-O-Ni bond. It is noteworthy that Ni (II) modified porous BN shows excellent removal percentage up to 99.769% for TC which far exceeds the pristine porous BN (70.853%) and most other reported adsorption materials. The maximum adsorption capacity calculated from the Langmuir model is 429.582 mg g⁻¹, confirming that Ni (II) modified porous BN has a remarkable performance for removing TC. In addition, the adsorption of TC onto Ni (II) modified porous BN followed pseudo-second-order kinetics and the equilibrium data fitted well with the Freundlich isotherm, revealing that chemisorption and multilayer adsorption was dominated. Finally, the results of DFT calculations further demonstrated that the effective adsorption of TC on Ni (II) modified porous BN could be ascribed to cation bridge interaction, π-π interaction, Van de Waals force and electrostatic interaction.