The ionic liquid-based coating is a coating for both porous and nonporous materials. As non-limiting examples, a porous substrate coated with the ionic liquid-based coating may be used to disinfect and remove microorganisms from air and water, to provide an antimicrobial surface for preventing microbial contamination, or to enhance filtration efficiency of the porous material for airborne and waterborne particulate matter without increasing flow resistance. As a further non-limiting example, a nonporous substrate coated with the ionic liquid-based coating may be used to form a surface capable of self-disinfection from microorganisms contacting surface. The ionic liquid-based coating includes at least one ionic liquid, an adhesive, and at least one additive, which may be a disinfectant, a viscosity modifier, a pH buffer, a fragrance, or combinations thereof.