Carbon quantum dots as a visible light sensitizer to significantly increase the solar water splitting performance of bismuth vanadate photoanodes

Research paper by Kai-Hang Ye, Zilong Wang, Jiuwang Gu, Shuang Xiao, Yufei Yuan, Yi Zhu, Yuanming Zhang, Wenjie Mai, Shihe Yang

Indexed on: 25 Jan '17Published on: 06 Jan '17Published in: Energy and Environmental Science


Here, we demonstrate that carbon quantum dots (CQDs), as a low cost, chemically stable, and environmentally friendly photosensitizer, can dramatically broaden the light absorption range to the entire visible range. Consequently, the NiOOH/FeOOH/CQD/BiVO4 (NFCB) photoanode has achieved a remarkable photocurrent density of 5.99 mA cm−2 at 1.23 V vs. RHE under AM 1.5G in KH2PO4 aqueous solution without a hole scavenger (pH = 7) and a record high applied bias photon-to-current efficiency of 2.29% at 0.6 V vs. RHE for BiVO4-based photoanodes. This novel NFCB photoanode could operate stably for 10 h with a Faraday efficiency of ∼95%, demonstrating the great potential of using CQDs for solar water splitting.

Graphical abstract 10.1039/C6EE03442J.gif