The PAM/LiCl precursor solution was prepared as described previously, stopping prior to the addition of TEMED. Filter papers (Whatman, Grade 4) were cut into 9 cm x 5 cm strips and carefully placed on the base substrate with a clean petri dish positioned underneath to collect any uncross-linked precursor. Following the addition of TEMED, the solution was stirred for three minutes before being evenly distributed over the filter paper. The substrate with filter paper was then subjected to UV light exposure while being rinsed with the precursor solution for 10 minutes. UV curing was continued overnight to ensure complete crosslinking.