Main content area

Sustainable Design of Hierarchically Porous Ag3PO4 Microspheres through a Novel Natural Template and Their Superior Photooxidative Capacity

Mandal, Subrata, Ananthakrishnan, Rajakumar
ACS sustainable chemistry & engineering 2018 v.6 no.1 pp. 1091-1104
2,4-dichlorophenol, Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, alanine, alginates, ambient temperature, collagen, design for environment, microparticles, microstructure, pH, photocatalysis, photocatalysts, photooxidation, porosity, reflectance spectroscopy, rhodamines, scanning electron microscopy, surface area, texture, thermogravimetry, transmission electron microscopy
Uniform hierarchical Ag₃PO₄ porous microspheres were synthesized for the first time by a sustainable route based on a novel natural bone glue (BG)-assisted one-step precipitation reaction at room temperature. By varying experimental conditions such as the bone glue content, template constituents (amino acid, alginic acid), precursor concentration, temperature, pH, and reaction time, we could tune the morphology, porosity, size, and properties of Ag₃PO₄. All of the phases, microstructures with different architectures, and textural properties of the Ag₃PO₄ were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller surface area analysis, and UV–vis diffuse reflectance spectroscopy. The oxidation state, local structure, and purity of the prepared Ag₃PO₄ were further characterized by X-ray photoelectron spectroscopy, Raman spectroscopy, and thermogravimetric analysis. The influence of the template on the morphology was characterized by syntheses of Ag₃PO₄ using different templates such as glycine, alanine, and alginic acid, and products such as pyramidal-shaped Ag₃PO₄, Ag₃PO₄ dodecahedra, and coiled-rod-like porous Ag₃PO₄ were obtained, respectively. This revealed that self-assembly of the collagen protein present in the bone glue plays a significant role as a structure-directing agent, crystal growth modifier, and aggregation-orienting agent in the formation of unique Ag₃PO₄ porous microspheres. Detailed photocatalytic studies on aqueous rhodamine B and 2,4-dichlorophenol (2,4-DCP) in the presence of Ag₃PO₄ porous microspheres exhibited enhanced photocatalytic degradation under visible light that was significantly higher than for other architectures. The findings of this study should offer new insights into the development of porous hierarchical materials as high-performance visible-light photocatalysts and their potential utilization in environmental sustainability.