Synthesis And Propetries Of Titanium Nitride Mesoporous Nunotube Arrays

Titanium dioxide （TiO₂） is an exceptional material that has many promising applications inareas ranging rfom photocatalysis to lithium batteires and electrochemical capacitors. Owing toporous structure, high accessible sirface area, eiffcient transport path of electron, and lower iondiiffision resistance, anodized titanium dioxide nanotube arrays（TiO₂NTAs） exhibit good kineticcharacteristics and safety. We can deposite pseudo-capacitive materials on NTAs electrodes fornovel composite electrodes with superior capacitive properties. TiCh have good UV lightphotocatalytic activity, but no visible light photocatalytic activity. Doping nitrogen can increasetheir optical activity by shifting the response from UV to visible region. Although thesemi-conduction nature of TiCh is crucial for many of applications, the limited conductivityprevents an even broader and eiffcient use in electrochemical capacitors applications that requirea fast electron transport. Doping nitrogen can improve conductivity of TiCh. The main results aresummarized as following:（1）The TiO₂nanotube arrays（TiO₂NTAs）were prepared by anodic oxidation Ti using aself-organized approach.The nitrogen doping titanium dioxide nanotube arrays（N-TiO₂NTAs）electrode was fabricated by annealing TiCh NTAs in ammonia atmosphere.The effection of theannealing temperature and nanotube length on the morphology and electrochemical propertieshas been investigated.As expected, TiO₂and TiN exhibit the lowest and highest carirer densityrespectively.Given that the morphologies of these samples are similar, they should have similarion diiffision rate.Therefore, the improved capacitance in N-TiCh and TiN samples should be dueto the enhanced electrical conductivity of electrode.TiN NTAs electrode has good high powerdischarge performance and excellent cycle stability.（2）Nickelhydroxide（Ni（OH）₂） was introduced and decorated along the nanotube inner wall andsurface by electrodeposition. It is discovered that the capacitance of the Ni（OH）₂decorating TiNNTAs （TiN/Ni（OH）₂） is much higher than that of the TiN NTAs.（3）MesoporousN-TiO₂nanotubes with different nitrogen content were obtained rfomas-prepared mesoporous TiN nanotubes by heat-treatment in air with different oxidationtemperature and heating preservation time. The eiffciency of N-doped TiO₂nanotubesphotocatalysts with different heat-treatment temperature were proved by the photocatalyticdegradation of Rhodamine B （RhB） under visible illumination. The result suggests nitrogen inTiO₂can enhance its photocatalysis under visible light and mesoporous N-TiO₂nanotubesprepared at450°C3h showed the highest photocatalysis.