Functionalization of hydroxyapatite derived from cockle (Anadara granosa) shells into hydroxyapatite–nano TiO2 for photocatalytic degradation of methyl violet

Abstract

Photocatalyst of hydroxyapatite-nano TiO 2 (HAp-nTiO 2) was prepared from phosphatation of calcined cockle (Anadara granosa) shells followed by dispersion of nano TiO 2 powder into HAp precipitate and calcination at 400°C for 2 h. The prepared material was characterized using X-ray diffraction, scanning electron microscope-energy dispersive X-ray spectrophotometry, gas sorption analysis, and UV-Vis diffuse reflectance spectrophotometry. The photocatalytic activity of the material was evaluated for methyl violet degradation over photocatalysis and photooxidation mechanism. The results showed that the homogeneous dispersion of TiO 2 in the HAp-nTiO 2 composite was achieved, as seen in the X-ray diffraction analysis, diffuse reflectance UV-Vis, and gas sorption analyses. The physicochemical and photocatalytic character of the composite exhibited the positive role of HAp as TiO 2 support in enhancing the photocatalytic activity with a higher turnover number and reusability property than that of pure TiO 2. It was also noted that the HAp-nTiO 2 composite demonstrated rapid methyl violet degradation over photooxidation rather than by photocatalytic mechanism.

Hydrothermally synthesized titanium/hydroxyapatite as photoactive and antibacterial biomaterial

“…The measured band gap energy seems to be reliable since the band gap energy of Ti20/HA is similar to a generally known value of 3.2 eV [ 27 ]. However, the values are less than those the values of TiO 2 /HA reported by previous works at similar Ti content [ 27 , 28 ]. Evaluation on correlation of the band gap energy values with crystallite size reflects that the higher band gap energy value is in correlation with the reducing size.…”

Photocatalytic activity of ZnO Doped Nano Hydroxyapatite/GO Derived from Waste Oyster Shells for Removal of Methylene Blue.

“…The photocatalyst was washed several times with distilled water, and as an adsorption method, the process was carried out for five cycles under similar conditions 99, 98, 93, 88, and 85 % of dye degradation occurred. At first two cycles remain stable, as more cycles are carried to show a slight decrease in its degradation efficiency, due to the loss of reactive sites of the GO sheet, Is Fatimah et al (2019). This work indicates the efficiency and the potential of reusing the prepared composites without a drastic decrease and was shown in Fig.…”

Green Synthesis of Antibacterial Nanocomposite of Silver Nanoparticle-Doped Hydroxyapatite Utilizing Curcuma longa Leaf Extract and Land Snail (Achatina fulica) Shell Waste

“…About 10 g of washed leaves were crushed and soaked in aquadest for 4 h and filtered to obtain C. longa leaf extract (called CLE). Biogenic calcium (CaO) was derived by calcining crushed land snail shells at 1050 °C [ 20 , 21 ]; previous investigation revealed the single phase of CaO obtained by this treatment. Chemicals consisting of AgNO 3 (>99%) and (NH 4 ) 2 HPO 4 (99%) were purchased from Merck (Darmstadt, Germany).…”