We developed a postsynthetic treatment to produce impurity n-type doped PbSe QDs with In3+ as the substitutional dopant. Increasing the incorporated In content is accompanied by a gradual bleaching of the interband first-exciton transition and concurrently the appearance of a size-dependent, intraband absorption, suggesting the controlled introduction of delocalized electrons into the QD band edge states under equilibrium conditions. We compare the optical properties of our In-doped PbSe QDs to cobaltocene treated QDs, where the n-type dopant arises from remote reduction of the PbSe QDs and observe similar behavior. Spectroelectrochemical measurements also demonstrate characteristic n-type signatures, including both an induced absorption within the electrochemical bandgap and a shift of the Fermi-level toward the conduction band. Finally, we demonstrate that the In3+ dopants can be reversibly removed from the PbSe QDs, whereupon the first exciton bleach is recovered. Our results demonstrate that PbSe QDs can be controllably n-type doped via impurity aliovalent substitutional doping.
Lu, Haipeng, et al. "<em>n</em>-Type PbSe Quantum Dots via Post-Synthetic Indium Doping." Journal of the American Chemical Society, vol. 140, no. 42, Sep. 2018. https://doi.org/10.1021/jacs.8b07910
Lu, Haipeng, Carroll, Gerard M., Chen, Xihan, Amarasinghe, Dinesh K., Neale, Nathan R., Miller, Elisa M., Sercel, Peter C., Rabuffetti, Federico A., Efros, Alexander L., & Beard, Matthew C. (2018). <em>n</em>-Type PbSe Quantum Dots via Post-Synthetic Indium Doping. Journal of the American Chemical Society, 140(42). https://doi.org/10.1021/jacs.8b07910
Lu, Haipeng, Carroll, Gerard M., Chen, Xihan, et al., "<em>n</em>-Type PbSe Quantum Dots via Post-Synthetic Indium Doping," Journal of the American Chemical Society 140, no. 42 (2018), https://doi.org/10.1021/jacs.8b07910
@article{osti_1487326,
author = {Lu, Haipeng and Carroll, Gerard M. and Chen, Xihan and Amarasinghe, Dinesh K. and Neale, Nathan R. and Miller, Elisa M. and Sercel, Peter C. and Rabuffetti, Federico A. and Efros, Alexander L. and Beard, Matthew C.},
title = {<em>n</em>-Type PbSe Quantum Dots via Post-Synthetic Indium Doping},
annote = {We developed a postsynthetic treatment to produce impurity n-type doped PbSe QDs with In3+ as the substitutional dopant. Increasing the incorporated In content is accompanied by a gradual bleaching of the interband first-exciton transition and concurrently the appearance of a size-dependent, intraband absorption, suggesting the controlled introduction of delocalized electrons into the QD band edge states under equilibrium conditions. We compare the optical properties of our In-doped PbSe QDs to cobaltocene treated QDs, where the n-type dopant arises from remote reduction of the PbSe QDs and observe similar behavior. Spectroelectrochemical measurements also demonstrate characteristic n-type signatures, including both an induced absorption within the electrochemical bandgap and a shift of the Fermi-level toward the conduction band. Finally, we demonstrate that the In3+ dopants can be reversibly removed from the PbSe QDs, whereupon the first exciton bleach is recovered. Our results demonstrate that PbSe QDs can be controllably n-type doped via impurity aliovalent substitutional doping.},
doi = {10.1021/jacs.8b07910},
url = {https://www.osti.gov/biblio/1487326},
journal = {Journal of the American Chemical Society},
issn = {ISSN 0002-7863},
number = {42},
volume = {140},
place = {United States},
publisher = {American Chemical Society (ACS)},
year = {2018},
month = {09}}