Development of p-n Heterostructures Using Phosphorene and SnO₂: Its Efficacy toward the Adsorption Study of CO₂ and Rose Bengal Dye

Adsorption-mediated methods for environmental pollution control are suitable as they are cost-effective and easy to use. Porous materials can play an important role in adsorption studies. Herein, we synthesized a p-n heterostructure of phosphorene and metal oxide using a simple hydrothermal approach. The synthesized material is porous in nature, with a surface area of 127.44 m²/g and pore volume of about 1.73 nm with appreciable thermal stability. As the material is microporous, we used it for the adsorption of CO₂ gas and dye. For CO₂ adsorption, we determined the CO₂ gas uptake according to the mass balance principle of the ideal gas equation, and it was found to be about 21.478 mol/kg. We have also studied different isotherm models to check the adsorption phenomena. Moreover, for dye adsorption, we have chosen the xanthene-derived rose bengal (RB) dye, which shows a removal percentage of about 92.02%. In the case of dye adsorption, the material shows good reusability and significant adsorption up to five cycles.