From 6 February through 17 March 2017, in cooperation with the Graduate School of Energy Science, the Institute of Advanced Energy (IAE) held its fifth ASEAN Young Researcher Training Program in the Energy Field. One student from the Joint Graduate School of Energy and Environment (JGSEE), King Mongkut's University of Technology Thonburi (KMUTT), Thailand, took part.
The participating student, Ms Sanglee Kanyanee, prepared visible light-responsive composite nanomaterials from titanium oxide and cadmium sulfide, to be used either as photocatalysts for glucose conversion or as photovoltaic components of hybrid solar cells, before characterizing their properties. She then synthesized these materials with a mixture made with titanium alkoxide and cadmium nitroxide as precursors, using cetyltrimethylammonium bromide (CTAB, a cationic surfactant) and sodium sulfide as promoters. The resulting product was calcined to yield pale yellow powder.
While titanium oxide itself has a relatively intense and broad light-emission peak of 400-500 nm, this emission was quenched in the materials Ms Sanglee Kanyanee produced, suggesting that energy transfer might have occurred from the titanium oxide to cadmium sulfide.
Regarding the powder's particles, their X-ray diffraction (XRD) peaks confirmed them to be 5-10-nm crystallites, although scanning electron microscopy (SEM) showed aggregated grains.
Ms Sanglee Kanyanee concluded from these results that in order to obtain nanoparticles, she must optimize the concentrations of the surfactant and promoter -- and the atomic ratios of the cadmium and titanium -- used, as well as the reaction time and temperature, and adjust the optical and electronic properties of the target materials accordingly.
Ms Sanglee Kanyanee having lunch with members of the host lab
Measuring absorption-desorption isotherms
Measuring photoluminescence
Preparing composite materials (1)
Preparing composite materials (2)
Preparing composite materials (3)
