| Ti O2 nano-materials have attracted much attention in recent years because of their unique morphology and physicochemical properties, high regulation, large surface area, excellent controllability, stability, and simple fabrication method. Ti O2 nano-materials have been intensively investigated for a variety of applications including solar energy harvesting, energy storage, photocatalysis, and biomaterials. Thus, using Ti O2 nano-materials as an alternative to current collector materials in supercapacitors has become an interesting area to be explored. However, the semiconductor nature of Ti O2 often leads to low electrochemical activity and poor conductivity thereby restricting its applications in the construction of high performance.In this work, the highly ordered anodic Ti O2 nanotube array(ATO) were fabricated on the surface of titanium foil by electrochemical anodization in a ethylene glycol solution containing 0.1M NH4 F for 1h followed by calcination with different atmosphere. The morphology, crystal structure, elements and absorption spectrum of samples were characterized by field emission scanning electron microscopy applications(FE-SEM), X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS). The results show that the samples do not show any significant change after calcination with different atmosphere. But the Raman spectra by Raman spectroscopy analysis shows that a slightly blue-shift and broadening of the Eg peaks which implied oxygen vacancies that originate from Ti4+ reduction. The sample followed by calcination with argon exhibit a very high average specific capacitance at the scan rate of 100 m V/s who is 84 times more than the sample treated with air and the photoelectrocatalytic degradation rate is 1.23 times more than the sample treated with air. The improved electrochemical performances and a high-performance photocatalysis can be attributed to the introduction of more oxygen vacancies by calcination with argon. Modification of the semiconductor nature of Ti O2 is important for its application in constructing high-performance supercapacitors and catalytic performance. Hence, the present study demonstrates a novel method involving fabrication of self-doped Ti O2 nanotubes by a simple cathodic polarization treatment on the pristine Ti O2 nanotubes to achieve improved catalytic performance, conductivity and capacitive properties of Ti O2. The results demonstrated that doping voltage, interelectrode distances and doping time play a key role in the electrochemical performances of self-doped Ti O2 nanotubes electrodes. The optimum doping process was: the doping voltage 5 V, the interelectrode distance 1.5 cm and the doping time 60 s.The self-doped Ti O2 nanotubes electrodes exhibited a high average specific capacitance at the scan rate of 100 m V/s who is 3.32 times and the photoelectrocatalytic degradation rate is 1.25 times more than the pristine Ti O2 nanotubes.Single crystalline Ti O2 nanowires on Ti foil by alkali(Na OH) hydrothermal followed by calcination with different atmosphere. The morphology, crystal structure, elements and absorption spectrum of samples were characterized by field emission scanning electron microscopy applications(FE-SEM), X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS). The results show that the samples do not show any significant change after calcination with different atmosphere. But the sample followed by calcination with argon exhibit a very high average specific capacitance at the scan rate of 100 m V/s who is 15 times more than the sample treated with air. The improved electrochemical performances can be attributed to the introduction of more oxygen vacancies by calcination with argon. Carbon coating on Ti O2 nanowires via a glucose-assisted hydrothermal treatment, and subsequent heat treatment, and Mn O2 nanoparticle decoration onto Ti O2@C nanowire arrays through immersion into KMn O4 aqueous solution at room temperature. In these unique composite materials, the carbon coating provides dual functionality. First, it significantly enhances electron transport throughout the composite materials, and second, it facilitates the deposition of Mn O2 nanoparticles on the surface of Ti O2@C nanowire arrays via a redox reaction with the KMn O4 solution. The Ti O2@C /Mn O2 nanowire arrays exhibited 540 times enhancement in capacitance compared to those of the pristine Ti O2 nanowire at the scan rate of 100 m V/s and it exhibit excellent cycling performance with 78.72% areal capacitance retained after 1000 cycles. |
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