Infiltration of VOPcPhO into porous alumina template grown by in situ method

Abstract

In this study, the fabrication of in-situ anodic alumina template (AAO) directly onto glass substrate is realized by varying the stirring speeds and molarity of phosphoric acid. Porous alumina template will then be used to infiltrate vanadyl 2, 9, 16, 23-tetraphenoxy-29H, 31H-phthalocyanine (VOPcPhO) prior to the formation of alumina:VOPcPhO nanocomposite. VOPcPhO has seen to fully infiltrate the template with the excess formation of VOPcPhO layer on top of the porous due to the lengthy immersion time of 6 hours. Uniformity and density of pore size, and available pore, can be respectively tuned by varying the stirring speeds (0 -300 rpm) and molarity of pore widening agent (0 -10 % of phosphoric acid). Roundedsphere shape of pores has been observed with higher transparency template is dominated by stirring the speed between 100 and 200 rpm. At these speeds, the template's pore size and pore density are highly homogeneous. Different molarity of phosphoric acid as a pore widening agent has an effect on the pore size and pore density. Occurrence of merging pores is observed by increasing the molarity of agent to 10% which unlikely to happen in the lower molarity of 5% phosphoric acid. Optical properties of alumina:VOPcPhO nanocomposites that identified from the characterization of UV-vis, photoluminescence (PL) and Raman spectroscopies, support the successful infiltration of VOPcPhO. Alumina:VOPcPhO nanocomposite has ability to absorb light at the longer wavelength and photon can be emitted by the nanocomposite at the respective energies.