We demonstrate herein the catalytic performance of unsupported Ni(OH)2 nanoparticles towards the dehydrogenation of primary alcohols to corresponding acids under aerobic conditions in refluxing toluene. An assortment of aromatic and aliphatic carboxylic acids/acids salts was prepared from corresponding alcohols in moderate to excellent yields. Interestingly, the protocol can also be employed to synthesize carboxylic acids on a gram scale, demonstrating the practical utility of the method. Mechanistic studies suggest that the reaction proceeds through an acceptorless dehydrogenation strategy and follow both Cannizzaro and catalytic dehydrogenative path. Broad substrate scope, operational simplicity, low cost, and reusability are the most interesting features of the current heterogeneous catalytic protocol described herein.