Role of PEG4000 in sol-gel synthesis of Sm2Ti2O7 photocatalyst for enhanced activity

PEG4000 was used as the template in sol-gel synthesizing of porous Sm2Ti2O7 material. Promoted crystallization of pyrochlore phase Sm2Ti2O7 occurs in the porous samples. The use of PEG4000 leads to particle refinement in the Sm(2)Ti(2)O7 samples. Metal-oxide bondings in the Sm2Ti2O7 are proven by FT far infrared spectra. Bandgap energy of the porous Sm2Ti2O7 slightly increases after the addition of PEG4000. BET surface area and pore volume in the samples constantly increase with rising PEG4000 amount. The addition of PEG4000 is beneficial to the production of hydroxyl radicals on Sm2T2O7 under UV light irradiation. The optimum photocatalytic activity and the largest decoloration efficiency belong to the sample using 1.5 g PEG4000. The conjugated chromophores in RBR-X3B molecule almost disappear after 120 min of photocatalytic degradation. (C) 2017 Elsevier B.V. All rights reserved.