Brundabana Naik1,2, Sun Mi Kim1,2, Chan Ho Jung1,2, Song Yi Moon1,2, Sang Hoon Kim3, Jeong Young Park1,2
1Center for Nanomaterials and Chemical Reactions, Institute for Basic Science, Daejeon 305-701, Republic of Korea
2Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea
3Center for Materials Architecturing, Korea Institute of Science and Technology (KIST), Seoul 136-791, Republic of Korea
Tóm tắt
Hierarchical N‐doped TiO2 nanostructured catalysts with micro‐, meso‐, and macroporosity are synthesized by a facile self‐formation route using ammonia and titanium isopropoxide precursor. UV–vis diffuse reflectance spectra confirm the red shift and band gap narrowing due to the doping of N species in the TiO2 nanoporous catalyst. Hierarchical macroporosity with fibrous channel patterning is observed and well preserved even after calcination at 800 °C, indicating thermal stability, whereas micro‐ and mesoporosity are lost after calcination at 500 °C. The photocatalytic activity of hiearchical N doped TiO2 catalysts loaded with Au is evaluated for H2 production reaction in visible light. The enhanced photocatalytic activity is attributed to the combined synergetic effect of N doping for visible light absorption, micro‐ and mesoporosity for an increase of effective surface area and light harvestation, and hierarchical macroporous fibrous structure for multiple reflection and effective charge transfer.
