Modification of g-C3N4 nanosheets by carbon quantum dots for highly efficient photocatalytic generation of hydrogen

• DOI: 10.1016/j.apsusc.2016.03.025
• Publication Date: 2016-03-05T20:06:21Z
• Authors: Kui Li; Feng-Yun Su; Wei-De Zhang
• Keywords: 7. Clean energy; 01 natural sciences; 0104 chemical sciences

Abstract Carbon quantum dots (CQDs) were deposited onto graphite-like carbon nitride nanosheets (CNNS) to form CNNS/CQDs composites. The prepared CNNS/CQDs composites exhibit much higher photocatalytic activity under visible light irradiation than pure CNNS do. The CNNS/CQDs-7 sample displays the highest photocatalytic performance, with H2 production rate of 116.1 μmol h−1, which is three times of that over pure CNNS (37.8 μmol h−1). Photoluminescence spectroscopy and photoelectrochemical (PEC) analysis reveal that the CQDs are favorable for trapping electrons and promoting the separation of photogenerated electron-hole pairs in CNNS. A possible photocatalytic mechanism of the enhanced photocatalytic performance for H2 generation over CNNS/CQDs will be proposed in this paper.