This paper is a study of ZnO doped TiO2 in various percentages ranging from 0% (undoped) up to 10%. The effect of doping was observed via the change in morphological, optical, electrical and physical properties of ZnO-TiO2 nanospheres. Hydrothermally grown nanospheres are used for removing contaminants photo-catalytically from waste water and also as photoanodes in dye-sensitized solar cells (DSSCs) with graphene as counter electrode. Of the many approaches that have been explored for purification of contaminated water, this work presents designing of an environmental friendly solution, based on easily available filter paper membrane and incorporating it with the synthesized catalyst for photodegradation of the harmful toxic substances. These reusable membranes assist in the photodegradation process by creating room for better light-catalyst-dye interaction via large surface sites. The spherically structured heterojunction of ZnO-TiO2 generates excitons that oxidize methyl orange (MO) and reduce harmful Cr(VI) to non-toxic Cr(III) with high efficacy. Additionally, the agile nanostructures were employed as efficient photoanode material by fabricating dye sensitized solar cells with graphene as counter electrode. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim