CuO/g-C3N4 nanocomposite for elemental mercury capture at low temperature

Graphitic carbon nitride (g-C 3 N 4 ) with unique and versatile properties has gained increasing research concerns. Here, CuO/g-C 3 N 4 nanocomposite is fabricated and employed for gas-phase mercury (Hg 0 ) removal at low temperature. Pure g-C 3 N 4 performs well toward Hg 0 adsorption at 40–200 °C with the optimal Hg 0 removal efficiency of ~ 54.5% at 120 °C. CuO-modification can significantly promote the Hg 0 capture ability of g-C 3 N 4 , probably due to the intimate interface contact of CuO and g-C 3 N 4 . The Hg 0 removal efficiency of g-C 3 N 4 first increases and then decreases with rising temperature, while temperature shows a promotional effect on Hg 0 removal efficiency of CuO/g-C 3 N 4 . Hg 0 is oxidized into HgO by the chemisorbed oxygen originated from the O–C–N structure of g-C 3 N 4 and the lattice oxygen of CuO. g-C 3 N 4 can be efficiently activated by modifying with CuO toward enhanced Hg 0 oxidation ability, presumably attributed to the electron transfer at the interface of CuO and g-C 3 N 4 .