To this solution,
100 ml of 0.1 M
NaOH/H2O solution was added with constant stirring for 1 h. The
nanocomposites powder was obtained after successive centrifugation
and dispersions in alcohol and the solid mass was dried at 75 ◦C
under vacuum for 4 h and calcinated at 200 ◦C for 2–3 h. The dried
ZnO–bentonite nanocomposite was then used for photocatalytic
experimentation.