NOVELTY - Bi-layer multifunctional coating for applying on different substrates comprises the first layer (bottom) that is a composite sol having silicon dioxide as one of the ingredient and the second ingredient that is titanium dioxide, zirconium dioxide or mercaptopropyl trimethoxy silane (MPTS) and the second layer (top) layer that is formed from a highly positive charge silicon dioxide nanoparticle sol over the first composite layer.    USE - The multi-functional coatings are useful for article that is used in solar absorber tubes and photovoltaic devices for harnessing solar energy and other applications, optics, display cases, and automobile rear mirror (claimed).    ADVANTAGE - The multi-functional coatings: exhibit antireflective, antifogging, UV, weather and scratch resistance properties and maximum mechanical stability to withstand up to 9H pencil hardness test and exhibits high weather and UV stability to withstand greater than 100h in UV and weather meter test (all claimed) and abrasion resistant; are super hydrophilic and exhibits ant-fogging even after drying at ambient temperature; and exhibit optical and super hydrophilic property even after noted after 100 hour weather and UV stability test.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for applying the bi-layer multi-functional antireflective coatings with anti-fogging, UV, weather and scratch resistance properties on the substrates comprising: cleaning the substrate thoroughly with a mild detergent solution, rinsing with water followed preferably with deionized water, and drying at 100 degrees C for 10-15 minutes in an air-oven; coating the cleaned substrate with a composite sol comprising titanium dioxide-silicon oxide or zirconium oxide-silicon dioxide or silicon dioxide-MPTS for the formation of the bottom layer (first layer) using a mixture of organo metallic precursors consisting mainly of silicon alkoxide as the major part, titanium alkoxide or zirconium alkoxide or silane compounds (MPTS or others), one low and one high boiling solvent, essentially alcohol, hydrogen chloride and water; drying the coated substrate at 80-100 degrees C for 15-30 minutes in oven; coating the dried substrate with a highly positive charge silicon dioxide nanoparticle sol (pH of 3-4) produced from Levasil 200E (RTM: 20% Silicon dioxide nanoparticle suspension) one low and one high boiling solvent; drying the above coated substrate at 80-100 degrees C for 15-30 minutes in an oven and curing at 400-500 degrees C for 2-4 hours for a coating on glass substrate and 80-100 for 2-4 hours for a coating on plastic substrates at a heating rate with 5-100 degrees C/minute.