Synthesis, characterization and optimization of N‐TiO₂/PANI nanocomposite for photodegradation of acid dye under visible light

Abstract

Polyaniline (PANI) as an excellent conducting polymer was used to prepare an organic-inorganic hybrid nanocomposite based on nitrogen (N)-doped titanium dioxide (TiO 2 ) under different synthesis conditions. Based on the DRS, XRD, FESEM, BET, XPS, and FT-IR results, the optical and structural properties of the asprepared composites were found to be affected by N-TiO 2 to aniline (ANI) molar ratio, reaction time, and initial pH of solution, which in turn influence the photocatalytic performance of nanocomposites. The experimental design methodology was used to study the simultaneous effect of these synthesis parameters on the Vis activity performance of N-TiO 2 /PANI nanocomposites for degradation of Acid Red 73. The degradation efficiency was significantly affected by the reaction time of polymerization, initial pH of solution, and interaction between the reaction time and N-TiO 2 / ANI molar ratio. The optimal synthesis conditions for maximum Acid Red 73 degradation efficiency (58.25%) were found to be a molar ratio of N-TiO 2 /ANI of 106.13 M, the reaction time of 487.42 min, and pH of 3.37. TEM images, N 2 adsorption-desorption isotherms and BET analysis of the as-prepared nanocomposites show the increase in surface area and porosity and decrease in agglomeration formation by adding nitrogen and PANI. The N-TiO 2 /PANI nanocomposites prepared at optimal synthesis conditions show higher visible activity compared to those modified with nitrogen or PANI only due to the synergistic effect between PANI and N doping. The mineralization studies of Acid Red 73 using the as-prepared nanocomposites show their ability to decompose approximately all organic compounds present in the solution. POLYM. COMPOS., 00:000-000,

Photocatalytic and Oxidative Synthetic Pathways for Highly Efficient PANI-TiO2 Nanocomposites as Organic and Inorganic Pollutant Sorbents

“…PANI-TiO 2 nanocomposites prepared via UV-light mediated green procedure were here studied and applied to pollutant removal in water. The preparation of PANI-TiO 2 composites has been quite extensively reported in the literature by using both preformed particles and TiO 2 sols/gels [12,29,37,38,75,76]. However, the present synthesis differs from the state-of-the-art as the photocatalytic activity of TiO 2 is directly exploited to initiate a green polymerization process, leading to materials with unique properties.…”

“…In the present case, materials prepared with low H 2 O 2 amounts showed the best performance in terms of pollutant removal capability, exhibiting a fast and complete MO and Cr(VI) abatement in tests on a broad concentration range. In the literature PANI-TiO 2 composites are mostly applied as photocatalyst for pollutant degradation [29,38,75,76], with the inherent limitations of this approach such as slow reaction kinetics, interfering effect of common electrolytes and possible accumulation of stable and toxic by-products. In this respect, the prepared nanocomposites show instead excellent sorption properties that can be used even in the presence of concentrated electrolytes (e.g., chlorides, bicarbonates), enabling the recovery of the pristine molecule upon mild treatments.…”

Catalytic Composite Systems Based on N-Doped TiO2/Polymeric Materials for Visible-Light-Driven Pollutant Degradation: A Mini Review

“…To date, there are still few papers regarding the coupling of CPs with N-doped TiO 2 . In particular, Mohammad Vaez et al have prepared N-TiO 2 /PANI nanocomposites by the polymerization of aniline in acidic media using ammonium persulfate in the presence of nanocrystalline N-doped TiO 2 particles for the degradation of the Acid Red 73 under visible-light irradiation [45]. The authors evidenced the enhancement of photocatalytic degradation of N-TiO 2 /PANI nanocomposites compared to N-doped TiO 2 or PANI only (Figure 8).…”

“…However, it must be considered that such systems can be activated only by UV light. Recent studies have been focused on the supporting provided to N-doped TiO 2 by various polymeric substrates, such as polyvinylidene fluoride (PVDF) [42], polypropylene (PP) [43], polytetrafluoroethylene (PTFE) [44], polyaniline (PANI) [45] and polystyrene (PS) [46][47][48][49][50]. Many authors reported that the coupling of semiconductors with polymers improves the photoactivity of N-doped TiO 2 for the degradation of water pollutants as well as for the inactivation of bacteria under visible-light irradiation (Table 2).…”

Poly(vinylidene fluoride‐hexafluoropropylene)/mesoporous graphitic carbon nitride composite membranes for photocatalytic methylene blue degradation and sensing applications

“…However, due to the accessibility and simplicity of catalytic materials, photocatalytic degradation has garnered considerable interest. [35][36][37][38][39] The extensively used nano-catalysts are Cu, 40,41 CdS, 42,43 ZnO, 44,45 32,[51][52][53][54] or its composites. 55 Compared to other polymetric semiconductor photocatalysts, graphitic carbon nitride (g-C 3 N 4 ) has the highest band gap of 2.7 eV, which works under visible light to degrade organic pollutants.…”