The impact of surface charge on the capability of organic NRs to deliver electrons to CODH, as well as its role on overall CO2 conversion to CO was studied next in detail. In a photocatalytic reaction, we employed methyl viologen (MV 2+ ) as an electron mediator to deliver electrons to CODH. To investigate the electron transfer suitability of synthesized organic NRs, a solution containing either POZ-M(-) NRs or POZ(+) NRs, with methyl viologen (MV 2+ ) and cysteine was purged with CO2. After light illumination (LED, 420 -750 nm, 50 mW•cm -2 ), the rise of the characteristic MV •+ peak (605 nm, Figure ) was monitored as a function of time (Fig. ). The corresponding reaction rates of MV 2+ reduction (υNRs-MV) by organic NPs in the presence of cysteine were estimated and collected in Table . By replacing the negatively charged POZ -M(-) NRs to positively charged POZ-M(+) NRs, we increased the rate of MV 2+ reduction from υNRs-MV = 195 to 320 µmol•L -1 •h -1 (Fig. ).