Water soluble reduced graphene oxide as an efficient photoluminescence quencher for semiconductor quantum dots

Chemically derived water soluble reduced graphene oxide (rGO) is synthesized via a two-step reduction approach assisted with sulfonation. X-ray photoelectron spectroscopy confirms the removal of oxygen-related groups from GO. The obtained rGO can effectively quench the photoluminescence (PL) of CdTe quantum dots. Concentration- and volume-dependent quenching behaviors are investigated to reveal the quenching mechanism. The Stern-Volmer plot shows exponential dependence on the rGO concentration, indicating that “sphere of action” model works when the extent of quenching is large.