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Abstract
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In this research, a series of CuZnTi-LDHs with different Cu2+/Zn2+ molar ratio were
synthesized by co-precipitation method with the purpose of improving the sonocatalytic
performance of ZnTi-LDH. All the LDH samples were synthesized by a facile co-precipitation
process. The as-prepared LDHs were characterized by Powder X-ray diffraction (XRD), Field
emission-scanning electron microscopy (FESEM), Transition electron microscopy (TEM),
Brunauer-Emmelt-Teller (BET) analysis, and UV-visible diffuse reflectance spectroscopy (DRS)
analysis. The results showed that Cu2+ substitution can significantly enhance the sonocatalytic
properties of ZnTi-LDH. The Methylene blue degradation percentage over ZnTi-LDH reached
30% in 90 min, whilst this percentage reaches 71% over CuZnTi-LDH (1:1). The role of the
Cu2+ incorporation on the observed enhancement in sonocatalytic performance was revealed by
investigating the effect of radical scavengers on degradation efficiency and DRS spectra of ZnTi-
LDH and CuZnTi-LDH (1:1). Benzoquinone (BQ), ammonium oxalate and tert-Bu lead to
22.5%, 53.5% and 74.6% decrease in degradation percentage by CuZnTi-LDH (1:1). However,
the degradation efficiency showed 16.6%, 3.3% and 63.3% reduction in the presence of BQ,
ammonium oxalate and tert-Bu respectively, in dye degradation by ZnTi-LDH. DRS spectra
demonstrated that the band gap of the LDH decreases by Cu2+ substitution. The effect of
operational parameters on sonodegradation was investigated as well. The kinetics of
sonodegradation reaction obeyed the first order reaction kinetics with R2 of 0.95.
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