The catalytic role of metallic substrates is a perfect starting point for growing high quality graphene layers by thermal decomposition of aromatics. However, metallic substrates quench the outstanding properties that make graphene the most promising material for future applications. Thus, protocols to transfer graphene to different technologically relevant substrates are mandatory. These transfer processes are cost inefficient and some can severely degrade the properties of graphene by introducing structural and chemical defects. As an alternative, we propose a novel, less invasive approach that is easily scalable. We target pristine graphene sheets grown on metals (Pt and Ir) and employ electrochemical oxidation at controlled potentials to introduce a single atom-thick hydroxide decoupling layer. To fully understand this decoupling a multi-technique characterization (STM, AFM, XPS and Raman) combined with theoretical studies (ab-initio calculations) of each step of the process has been undertaken.