Carbon nanosphere templates for the preparation of inverse opal titania photonic crystals by atomic layer deposition

• Published in: Applied surface science Vol. 504; p. 144443
• Main Authors: Bakos, László Péter, Karajz, Dániel, Katona, András, Hernadi, Klara, Parditka, Bence, Erdélyi, Zoltán, Lukács, István, Hórvölgyi, Zoltán, Szitási, Géza, Szilágyi, Imre Miklós
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 28.02.2020
• Subjects: Carbon nanospheres; Inverse opal photonic crystal; Photocatalysis; TiO2; Carbon nanospheres; Photocatalysis; TiO2; Inverse opal photonic crystal
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.144443

[Display omitted] •Carbon nanospheres are novel templates for inverse opal photonic crystals.•Visible absorption of TiO2 can be increased using the slow photon effect.•TiO2 visible absorption is tuned by different template size for inverse opals.•A new method has been elaborated for measuring photocatalysis over films.•Photocatalysis can be followed on the surface with UV–Vis and Raman spectroscopy. Carbon nanospheres were used as templates for the first time to prepare titania inverse opal photonic crystal. From the spheres, opal colloid crystals were made by vertical deposition on microscope slides, and TiO2 was grown on them using atomic layer deposition (ALD). For this technique, the relatively high thermal stability and the presence of oxygen containing functional groups on the surface of the carbon spheres are beneficial. Subsequent annealing burned out the template spheres, leaving behind the inverse opal structures. The upper solid TiO2 layer was removed with argon ion sputtering. The samples were characterized with SEM, Raman spectroscopy, XRD, EDX, UV–Vis diffuse reflectance spectroscopy and their photocatalytic activity was investigated in decomposing organic dyes under UV and visible illumination. A new approach was used to test photocatalysis on the surface by utilizing UV–Vis reflectance and Raman spectroscopy in conjunction.