Electrocatalytic Degradation of Azo Dye by Vanadium-Doped TiO2 Nanocatalyst

Abstract

In this work, nano V/TiO2 catalysts at different molar ratios were prepared and fabricated as the electrocatalytic electrodes for electrocatalytic degradation. The effect of the vanadium doping on the surface morphology, microstructural, and specific surface area of V/TiO2 catalysts was probed by field emission scanning electron microscope (FESEM) x-ray diffractometer (XRD), and Brunauer–Emmett–Teller (BET), respectively. Afterward, the solution of Acid Red 27 (AR 27, one kind of azo dye) was treated by an electrocatalytic system in which the nano V/TiO2 electrode was employed as the anode and graphite as the cathode. Results demonstrate that AR 27 can be effectively degraded by the nano V/TiO2 electrodes; the highest removal efficiency of color and total organic carbon (TOC) reached 99% and 76%, respectively, under 0.10 VT (molar ratio of vanadium to titanium) condition. The nano V/TiO2 electrode with high specific surface area facilitated the electrocatalytic degradation. The current density of 25 mA cm−2 was found to be the optimum operation for this electrocatalytic system whereas the oxygen was increased with the current density. The electricity consumption of pure TiO2 and nano V/TiO2 electrode in this electrocatalytic system was around 0.11 kWh L−1 and 0.02 kWh L−1, respectively. This implies that the nano V/TiO2 electrode possesses both high degradation and energy saving features. Moreover, the nono V/TiO2 electrode shows its possible repeated utilization.

Enhancement of oxygen reduction reactivity on TiN by tuning the work function via metal doping

“…2(iv), sheets can be observed only for Ti 0.8 V 0.2 O x N y , indicating that dissolved V ions interconnect the particles. Similar results were reported by Yao and Wang 22 and Chang et al 23 for V-doped TiO 2 as an electrode for sodium ion batteries and a catalyst for the degradation of azo dyes, respectively.…”

Ab Initio Prediction of the Redox Potentials of 3d Transition Metals Embedded in a Semiconducting Host Lattice

“…These intentionally introduced point defects are well-known to create local structural distortions and in-gap electronic states, [16][17][18][19][20] which may significantly modify the electronic, magnetic and/or optical properties of host materials. In the case of the TiO2 compound, the introduction of transition metal (TM) dopants has been reported to enhance photocatalytic, [21][22][23][24][25][26][27][28][29] electrocatalytic 30,31 or ferromagnetic [32][33][34][35][36][37][38][39][40][41] properties, but also to alter the irreversible anatase-torutile phase transition. 42 It remains evident that properties strongly depend on the electronic configuration of impurities, which is usually discussed through their oxidation state.…”

“…These intentionally introduced point defects are well-known to create local structural distortions and in-gap electronic states, − which may significantly modify the electronic, magnetic, and/or optical properties of host materials. In the case of the TiO 2 compound, the introduction of TM dopants has been reported to enhance photocatalytic, − electrocatalytic, , or ferromagnetic − properties but also to alter the irreversible anatase-to-rutile phase transition …”

Advanced Synthesis and Characterization of Vanadia/Titania Catalysts through a Molecular Approach

“…More specifically, vanadia supported on titania catalysts is a very important material for many industrial processes, including those of environmental interest. It is worth mentioning dehydrogenation reactions [2][3][4][5], oxidation processes [6][7][8][9][10][11], water treatment through photocatalysis [12,13], and electrocatalysis [14]. However, the technology in which these catalysts are widely used is the selective catalytic reduction (SCR) of NO x , using mainly NH 3 as a reductant.…”