Higher concentration of trivalent and hexavalent chromium (percent to mg L -1 ) can be effectively removed from water by adsorption or precipitation process, but difficult to remove lower concentration (<0.25 mg L -1 ) upto prescribed limits of World Health Organization (WHO) and United State-Environment Protection Agency (US-EPA). The lower concentration of chromium can be effectively removed using reverse osmosis system. In the proposed study we have successfully removed higher to lower concentration (20 to 0.1 mg L -1 ) of trivalent and hexavalent chromium using alone polyvinylpyrrolidone (PVP) functionalized zinc peroxide (ZnO 2 ) nanomaterial below detection limit (0.001 mg L -1 ) of Flame Atomic Absorption Spectrophotometer instrument (FAAS) within 15 minutes. The utilized nanomaterial alone act as oxidizing as well adsorbing agent, and purify water upto safe potability limits. The adsorption capacity of functionalized ZnO 2 nanomaterial for total chromium was found to be 4.98 mg g -1 which is much better than the several other materials reported in the literature for chromium removal. A process patent for the synthesis of varying sizes functionalized ZnO 2 nanomaterials has been granted in United State