“…In the synthesis of metal oxides (homo, hetero or doped), hydrothermal syntheses in superheated or supercritical water can offer many advantages over conventional preparative methods including fewer synthetic steps and significantly faster reaction times [46][47][48][49][50][51].There are currently very few scientific reports utilizing hydrothermal routes for decorating graphene with nanoparticles [52][53][54][55].However, the current hydrothermal syntheses are conducted in batch reactors, which are time consuming and give little control over product properties such as crystallinity, size, etc.…”