Synergistic hybrid of polypyrrole microtubes and magnesium silicates for efficient organic pollutant removal

Abstract

Wastewater contaminated with dyes has garnered significant attention due to its detrimental effects on the environment and public health. Adsorption, being a non-toxic, cost-effective, and highly efficient method, is widely employed for dye removal. Tubular structured materials stand out as attractive adsorbents because of their high specific surface areas and rapid mass transfer capabilities. In this study, we present, for the first time, the synthesis of tubular structured PPy@MgSiO₃ nanocomposites through an innovative approach combining polymerization, the Stöber method, and subsequent hydrothermal treatment. These nanocomposites, featuring hierarchical MgSiO₃ nanosheets (NSs), PPy interlayers, and a tubular structure with an exceptional specific surface area, demonstrate remarkable adsorption capabilities. Specifically, they effectively remove methylene blue (MB) from water within 180 min at room temperature. The adsorption process primarily adheres to Lagergren pseudo-first-order kinetics, while the Langmuir isotherm model provides an excellent fit, indicating a very high monolayer adsorption capacity of 224.57 mg/g at ambient temperature. Moreover, this protecting layer assisted Stöber method can be extended to synthesize tubular FeOOH@CuSiO₃ composites, which was also proved to be an excellent dye adsorbent. This work pioneers a straightforward strategy for crafting different kinds of hierarchical tubular metal silicate composites for dye removal.