The direct recycling of waste and residues has become essential due to the depletion of natural resources, increasing pollution, and greenhouse emissions. Hence conversion of waste/ biomass to valuable materials and energy (i.e., valorization) is crucial. We have been working for designing and development of heterogeneous and homogeneous catalysts for the valorization of cellulose and hemicellulose into sugars, sugar derivatives (furfural, HMF, sugar alcohols etc.), homogeneous and heterogeneous catalysts for the oxidation (FDCA, gluconic acid, furoic acid), hydrogenation (sorbitol, xylitol, furfuryl alcohol, DMF) of sugars and sugar derivatives, depolymerization of lignin into aromatic monomers and their further conversion via hydrodeoxygenation into hydrocarbons, development of new materials for their applications in biomass conversion.