Synergetic photocatalytic-activity enhancement of lanthanum doped TiO2 on halloysite nanocomposites for degradation of organic dye

Strainer-Separable TiO2 on Halloysite Nanocomposite-Embedded Alginate Capsules with Enhanced Photocatalytic Activity for Degradation of Organic Dyes

“…The separation time can be shortened by increasing the water flow rate and broadening the mesh size of the strainer. Although the TiO 2 @HNT/Alcaps had lower photocatalytic activity ( k 1 : 0.0321 min −1 ) compared to the nanocatalysts (TiO 2 @HNTs, k 1 : 0.1206 min −1 ) [ 19 ], our catalysts possess economic benefits for the treatment of a large amount of wastewater, considering that the centrifugation of a large amount of wastewater would require huge equipment and energy. Without the centrifugal separation process, the TiO 2 @HNT/Alcaps could maintain their photocatalytic activity at under 10% loss in five cycle reuses, showing the potential of reusable catalysts for industrial use ( Figure 7 and Figure S3 ).…”

“…TiO 2 nanoparticles on the HNT surface were synthesized by the sol-gel method [ 19 , 34 ] ( Figure 2 a). In brief, 5 mL of TTIP was dissolved in 24 mL of isopropanol.…”

“…The negatively charged Si-O-Si surface structure and positively charged Al-OH internal structure can adsorb cationic dyes (methylene blue, neutral red, crystal violet, and malachite green) and anionic dyes (congo red and methyl orange), respectively. [ 10 , 11 , 12 , 13 , 14 , 15 , 16 ] Although several TiO 2 @HNTs composites have shown enhanced activity in photocatalytic degradation of organic pollutants [ 17 , 18 , 19 , 20 , 21 , 22 , 23 ], their nanosize still requires complicated separation processes, hindering the catalysts’ retrieval.…”

Halloysite Nanotubes: Smart Nanomaterials in Catalysis

“…Different studies dealing with the photodegradation of antibiotics or organic dyes from aqueous solution by means of valuable nanocatalysts based on metal nanoparticles supported on HNTs, both pristine and modified, have been reported (Table 3) [48,[65][66][67][68][69][70]. Recently, to improve the photocatalytic properties of TiO 2 NPs, Lee et al synthetized a La 3+ doped TiO 2 on HNTs (La/TiO 2 @HNTs) catalyst by a two steps procedure based on a sol-gel process followed by a sonochemical method [79]. First, the authors synthetized TiO 2 NPs by a low-temperature sol-gel process using titanium(IV) isopropoxide precursor supported on the HNTs surface.…”

“…Then, the immobilized TiO 2 NPs were doped with lanthanum nitrate hexahydrate precursor in a sonochemical method (Figure 5). Recently, to improve the photocatalytic properties of TiO2 NPs, Lee et al synthetized a La 3+ doped TiO2 on HNTs (La/TiO2@HNTs) catalyst by a two steps procedure based on a sol-gel process followed by a sonochemical method [79]. First, the authors synthetized TiO2 NPs by a low-temperature sol-gel process using titanium(IV) isopropoxide precursor supported on the HNTs surface.…”