Synthesis of calcium aluminate nanoflakes for degradation of organic pollutants

Abstract

Calcium aluminate nanoflakes possessing a single crystalline orthorhombic Ca₅Al₆O₁₄ phase and a thickness of about 50 nm were synthesized via a simple route. The elements O, Al, and Ca were confirmed in the nanoflakes by element mapping and X-ray photoelectron spectroscopy. Formation and growth of the nanoflakes can be explained by a nucleation and crystalline growth process. The nanoflakes exhibit a band gap of 3.87 eV which entails good photocatalytic activity towards gentian violet which, in aqueous solution at a concentration of 10 mg L⁻¹, can be entirely degraded within 100 min upon irradiation of a 175 W mercury lamp using 1 g L⁻¹ calcium aluminate nanoflakes as catalyst. The reaction rate constant is 0.032 min⁻¹ which is six times higher than that using calcium aluminate nanostructures obtained from different conditions. The nanoflakes are recoverable and possess good stability for the gentian violet degradation.

Keywords:

• Ca aluminate nanoflakes
• hydrothermal synthesis
• gentian violet
• photocatalysis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Natural Science Foundation of Anhui Province of P. R. China [2008085ME172], National Scholarship Fund of China Scholarship Council (CSC) [202008340046] and Student Innovation and Entrepreneurship Training Program of Anhui Province of P. R. China [S202210360176].