For exfoliation of the Cr2O3/rGO film it was cut into small pieces and soaked in DI water and sonicated for 7 hours. After the Cr2O3/rGO film delaminates from the silver substrate the resulting solution was mixed with 100% ethanol (volume ratio 1:4). Via drop casting Cr2O3/rGO flakes were placed onto SiO2/Si substrate (90 nm oxide thickness). The flakes were characterized with Scanning electron microscopy (SEM, F.E.I. Nova NanoSEM 230 and NanoSEM 450) and Raman spectroscopy (Renishaw inVia Raman Microscope, 532 nm excitation laser).