Sustainable and Cost-Effective Synthesis of Single-Layered 2D MIL-53(Al) Nanosheets for Efficient H₂S Capture

Hydrogen sulfide (H 2 S) poses negative effects on the realm of energy storage and conversion and human health owing to its corrosivity, catalyst poisoning, and toxicity. Hence, removing H 2 S from gas streams plays a crucial role in sections of gas-derived energy production and human life. Metal–organic frameworks (MOFs) have been extensively studied for H 2 S adsorption, thanks to their large surface area and tunable structure. This work presents a sustainable and cost-effective synthesis of single-layered two-dimensional (2D) MIL-53(Al) nanosheets with excellent ability for H 2 S adsorption. The 2D MIL-53(Al) is synthesized by an organic solvent-free protocol using plastic waste as a precursor source. Synthetic conditions are optimized to obtain a high-yield synthesis process and a material with tunable properties. The MIL-53(Al) nanosheet (thickness of 6.7 Å) with a single-layered structure is confirmed by scanning transmission electron microscopy and atomic force microscopy, which has never been reported yet. The material possesses a large surface area of 1112 m 2 ·g –1 and good chemical and thermal stability. Regarding H 2 S adsorption, the 2D MIL-53(Al) exhibits a H 2 S capacity of 556 mg·g –1 under ambient conditions, and its potential regenerability is proven. These performances arise from facile exposure of H 2 S molecules to adsorptive sites in the 2D framework and reversible adsorption of the material toward H 2 S. This study opens a pathway for designing 2D MOFs in the field of H 2 S adsorption and provides a well-designed 2D MOF for further research strategies.