Polyaniline (PANI) is one of the most widely studied conducting polymers due to its many interesting properties like chemical and environmental stability, redox reversibility, and ease of synthesis . The conducting or semiconducting nature of PANI has been used in various applications, like biosensors , supercapacitors , metal-semiconductor devices , actuators , secondary batteries , light emitting diodes , photovoltaic devices , field effect transistors , laser printing , anticorrosion coating , etc. However, the main drawback of PANI is its poor solubility in water . Till date, the most common method to improve the solubility, and hence processability of PANI in water is sulfonation, in which the emeraldine salt form of PANI is treated with chlorosulfonic acid in an inert solvent . The sulfonated PANI (SPANI) so prepared is water soluble at all pH values, though at the cost of conductivity to some extent due to the presence of strong electron withdrawing sulfonic acid (-SO3H) groups .