Mesoporous tellurium oxide incorporated g-C3N4 for boosted photoinduced – visible-light reduction of Hg(II)

Abstract

Two-dimensional (2D) tellurium oxide (TeO2) nanoparticles were homogenously incorporated porous graphitic carbon nitride (g-C3N4) utilizing a simple synthesis sol–gel approach in the occurrence of soft and hard templates. The photocatalytic performance of TeO2/g-C3N4 photocatalysts was performed to reduce Hg(II) ions during visible light illumination. α-TeO2 NPs as tetragonal phases are uniformly scattered with small particle size (15 nm) onto layer structure of g-C3N4. The highest photocatalytic performance (100%) within 40 min is 3 %TeO2/g-C3N4 photocatalyst, and it was enhanced 6.66 and 3.7 folds larger than bare g-C3N4 and TeO2. The rate constant of 3 %TeO2/g-C3N4 photocatalyst is fostered nearly 7.6 and 14.3 times larger than the bare TeO2 NPs and g-C3N4. TeO2 with a nanoscale diameter size (∼15 nm) exhibited a higher photoreduction rate and faster kinetics. Such high reduction ability over TeO2/g-C3N4 photocatalyst was ascribed to the advantageous construction of TeO2/g-C3N4 heterojunction, the synergistic effects of TeO2 and g-C3N4 and the enhancement in electron mobility and efficient electrons and holes separation rate. Owing to such advantageous properties, the 2D- TeO2/g-C3N4 photocatalyst presents promising application potentials as a high-performance photoreduction process.