Colloidal quantum dots (QDs) are attractive materials for application in photovoltaic and photoelectrochemical devices, due to their unique properties including band energy tunability, high absorption coefficient and multiple exciton generation. Here, we construct continuous and automated microfluidic reactors for the synthesis of CdSe QDs, and apply the synthesized QDs to the QD-sensitized solar cells (QDSCs) as a photosensitizer. The spectral range, quantum yield (QY) and surface states of QDs are facilely and finely tuned by controlling the flow rates of precursor solutions and solvents in the microfluidic reactors. The photovoltaic and photoelectrochemical performances of QDSCs are strongly affected by both the spectral range and QY of CdSe QDs. In particular, the conversion efficiency is enhanced by about 19% with the increase in QY from 15.4% to 23.2%, at the same spectral range. Furthermore, the enhanced surface purity of QDs by modified synthetic condition leads to the reduced electron recombination in the QD-sensitized TiO2 electrodes, which is confirmed by electrochemical impedance analysis. This study demonstrates the great potential of microfluidic system for the synthesis QDs and their application in photoelectrochemical solar cells.
Bibliographical noteFunding Information:
B.S.K. acknowledges the financial support by Regional Industry Nurturing Program “Development of high sensitive and functional organic/inorganic hybrid plastic composite for LED (Project No. A010400068)”, which is funded by MOTIE (Ministry of Trade Industry & Energy). M.J.K. acknowledges the funding support by development program “Development of high drapability of textile type dye-sensitized solar cell materials and outdoor applications (project NO. 10052064)” funded by MOTIE and the Technology Development Program to Solve Climate Changes (2015M1A2A2056824) funded by the National Research Foundation under the Ministry of Science, ICT & Future Planning, Korea.
- Microfluidic Reactors
- Quantum Dots
ASJC Scopus subject areas
- Chemical Engineering(all)