Na2SO4-assisted synthesis of hexagonal-phase WO3 nanosheet assemblies with applicable electrochromic and adsorption properties

Abstract

For the first time, a mesoporous hexagonal-phase Na_0.17WO_3.085·0.29H₂O nanosheet/microflower hierarchical structure has been synthesized employing a one-pot hydrothermal process with the assistance of Na₂SO₄. It is shown that Na₂SO₄ not only acts as a stabilizer to facilitate the generation of a metastable hexagonal phase, but also function as a structure directing agent to assist the construction of nanosheet assemblies. The formation mechanisms have been rationalized. The materials have been thoroughly characterized by XRD/BET/FESEM/EDX/TEM/TGA. This hexagonal-phase Na_0.17WO_3.085·0.29H₂O nanosheet/microflower hierarchical structure exhibits applicable electrochromic and adsorptive properties due to its unique crystallographic configuration and microstructures, promising its application in energy-saving smart windows and wastewater treatment.