Functionalization of TiO2 nanotubes with palladium nanoparticles for hydrogen sorption and storage

The use of hydrogen as an energy carrier is an attractive solution toward addressing global energy issues and reducing the effects of climate change. Design of new materials with high hydrogen sorption capacity and high stability is critical for hydrogen purification and storage. In this study, titanium dioxide nanotubes (TiO₂NTs) were modified with palladium nanoparticles (PdNPs) utilizing a facile photo-assisted chemical deposition approach. Electrochemical anodization was employed for the direct growth of TiO₂NTs. The PdNP functionalized TiO₂NTs (TiO₂NT/Pd) were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The hydrogen sorption behaviours and stability of the TiO₂NT/Pd nanocomposites were investigated and compared with nanoporous Pd networks that were deposited on a bulk titanium substrate (Ti/Pd) using cyclic voltammetry (CV) and chronoamperometry (CA). Our studies show that the TiO₂NT/Pd nanocomposites possess a much higher hydrogen storage capacity, faster kinetics for hydrogen sorption and desorption, and higher stability than the nanoporous Pd.