The invention provides methods and materials for decontamination of surfaces and fabrics, such as non-woven fabrics, that are contaminated with infestations of microorganisms such as bacteria. Biocidal oligomers having conjugated oligo-(aryl/heteroaryl ethynyl) structures and comprising at least one cationic group can be used to decontaminate infested surfaces in the presence of oxygen and, optionally, illumination. Fibers incorporating biocidal oligomers having conjugated oligo-(aryl/heteroaryl ethynyl) structures and comprising at least one cationic group, wherein the oligomer is physically associated with or covalently bonded to, or both, the fiber-forming polymer can be used to form non-woven mats. Biocidal non-woven mats prepared by methods of the invention, incorporating the biocidal oligomers, can be used to suppress bacterial growth in wound and surgical dressings and personal hygiene products.