Jiabei Zhou

Synthesis and characterization of tungsten carbide and application to electrocatalytic hydrogen evolution

Tungsten carbide was synthesized and further hydrogen treated to remove excess carbon. The obtained WC with different carbon contents was investigated by XRD, TG, SEM, EDS, BET and Raman. This work evaluated the effect of excess carbon on the properties of WC as a support for platinum. The hydrogen evolution reaction (HER) activity was used as a metric to test the effect of excess carbon on the electrochemical activity in 0.5 M sulfuric acid using a linear sweep voltammogram (LSV). Pt deposited on WC after hydrogen treatment exhibited a better electrocatalytic performance than Pt deposited on untreated WC. The investigations show that the presence of excess carbon is harmful to HER activity.

Study on transformation mechanism of lithium titanate modified with hydrochloric acid

The effects of the concentration of hydrochloric acid and treatment time on the transformation of Li2TiO3 were studied in detail. The results demonstrate that lithium ions are easily removed from the (−133) and (−206) planes. In contrast, Li+ extraction requires a longer time for the (002) and (−131) planes. A mixture of the anatase and rutile phases, pure rutile, and pure anatase can be generated by treating Li2TiO3 with a suitable concentration of hydrochloric acid for an appropriate amount of time. The phase(s) that are present significantly affect the cyclic adsorption performance of a titanium lithium ion sieve and the dissolution of Ti. The transformation from H2TiO3 particles to TiO2 primarily occurs via the dissolution-recrystallization process. The electrophilic H+ and highly electronegative Cl− affect the Ti–O bond, resulting in the destruction of the Ti–O bond in TiO6 octahedrons, promoting the structural rearrangement of anatase to rutile TiO2.