Coating method Time used References
Stober method 24 h [4]
Reverse Microemulsion method > 16 h [8]
General method > 16 h [9]
Reverse Microemulsion method 48 h [7]
Sol-gel method 6-48 h [1]
Microemulsion method 24 h [6]
Microemulsion method 20 h [5]
Modified Sol-gel method(Our method) 4 h -
Table 1: Total coating process.