Mixed-Phase MOF-Derived Titanium Dioxide for Photocatalytic Hydrogen Evolution: The Impact of the Templated Morphology

Abstract

Herein, we explored a simple metal-organic framework (MOF) mediated synthesis for the controlled preparation of pure and mixed phase titania (TiO2) nanoparticles. Scanning electron microscopy images revealed that the MOF-derived TiO2 retain the MOF crystal shape, and through powder X-ray diffraction and X-ray photoelectron spectroscopy, it is demonstrated that the crystal-template is composed of nanosized TiO2 rutile and anatase particles. The presence of both TiO2 rutile and anatase phases in the crystal-template enhances the interactions between them, thus suppressing the electron-hole recombination. This has an impact toward the photocatalytic reduction of water as the templated MOF-derived TiO2 outperforms the commercial (P25 Degussa), titanium isopropoxide-derived and non-templated MOF-derived TiO2. Our study demonstrates that the morphologicallyinduced high charge separation efficiency afforded by using MOF crystals as precursors can lead to the generation of catalytically more active materials that can challenge existing photocatalysts in the field of hydrogen generation.

Bimetal–organic framework derived multi-heterostructured TiO2/CuxO/C nanocomposites with superior photocatalytic H2generation performance

“…TiO 2 /CuO x , Cu 2 O/g-C 3 N 4 ) to spatially separate the photogenerated electrons and holes. 3,4,[20][21][22] Moreover, the number of active sites for the photocatalytic water reduction reaction is increased with the help of noble metal (e.g. Pt, Au and Pd) cocatalysts.…”

Metal–Organic Frameworks for Photocatalytic Water Splitting

“…This behavior was proven in a study published by Stylianou and coworkers. [ 92 ] In this work, alternating the calcinated temperature allows the controllable formation of anatase and rutile ( Figure a). Particularly, MIL‐125‐NH 2 calcinated at 400 °C generated only 2 wt% of rutile (98 wt% of anatase).…”

Metal–organic framework derived nanomaterials for electrocatalysis: recent developments for CO2 and N2 reduction

“…Singh et al have grown Fe/Ni-MIL-53 over carbon cloth via electrophoretic deposition and pyrolyzed at a different temperature to achieve metal embedded carbons [ 47 ]. Kampouri et al synthesized mixed face TiO 2 embedded in a carbon framework, by pyrolyzing a Ti-based MIL-125-NH 2 at various temperatures [ 48 ]. Using post-synthesis modification strategy Chen et al have successfully anchored W atoms on N-doped carbon matrix derived from the mixing of WCl5 and UiO-66-NH2 at an elevated temperature 900 °C [ 24 ].…”