Environmentally-stable eco-friendly pectin-silica bio-hybrid foams for soil remediation

Abstract

Here we present a new class of hybrid material composed of a polysaccharide macroporous core surrounded by a thin silica layer as new adsorption platforms for the retention of organic pollutants in soil media. The core-shell hybrid foams were fabricated by ice-templating to create highly anisotropic pectin foams, followed by vapor phase silica deposition. The structural stability of the hybrid foams was tested in compression, reaching a Young's Modulus up to 5 MPa, but also, and more importantly, in direct contact with wet soils over more than one month. Hybrid foams showed a sorption capacity for a toxic dye nearly two orders of magnitude higher than the surrounding soils. Altogether, these hybrid foams combine all chemical, structural and functional properties required to be effective materials for soil depollution and, thanks to their easy-recovery, should compete with common particulate sorbents.