Abstract
Chemical doping of organic semiconductors has been recognized as an effective way to enhance the electrical conductivity. In perovskite solar cells (PSCs), various types of dopants have been developed for organic hole transport materials (HTMs); however, the knowledge of the basic requirements for being efficient dopants as well as the comprehensive roles of the dopants in PSCs has not been clearly revealed. Here, three copper-based complexes with controlled redox activities are applied as dopants in PSCs, and it is found that the oxidative reactivity of dopants presents substantial impacts on conductivity, charge dynamics, and solar cell performance. A significant improvement of open-circuit voltage (V oc ) by more than 100 mV and an increase of power conversion efficiency from 13.2 to 19.3% have been achieved by tuning the doping level of the HTM. The observed large variation of V oc for three dopants reveals their different recombination kinetics at the perovskite/HTM interfaces and suggests a model of an interfacial recombination mechanism. We also suggest that the dopants in HTMs can also affect the charge recombination kinetics as well as the solar cell performance. Based on these findings, a strategy is proposed to physically passivate the electron-hole recombination by inserting an ultrathin Al 2 O 3 insulating layer between the perovskite and the HTM. This strategy contributes a significant enhancement of the power conversion efficiency and environmental stability, indicating that dopant engineering is one crucial way to further improve the performance of PSCs.
| Original language | English |
|---|---|
| Pages (from-to) | 10452-10462 |
| Number of pages | 11 |
| Journal | ACS Nano |
| Volume | 12 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 12 Sep 2018 |
Keywords
- Al O
- chemical dopants
- hole transport materials
- interfacial recombination
- passivation
- perovskite solar cells
Cite this
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Chemical dopant engineering in hole transport layers for efficient perovskite solar cells : insight into the interfacial recombination. / Zhang, Jinbao; Daniel, Quentin; Zhang, Tian; Wen, Xiaoming; Xu, Bo; Sun, Licheng; Bach, Udo; Cheng, Yi Bing.
In: ACS Nano, Vol. 12, No. 10, 12.09.2018, p. 10452-10462.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - Chemical dopant engineering in hole transport layers for efficient perovskite solar cells
T2 - insight into the interfacial recombination
AU - Zhang, Jinbao
AU - Daniel, Quentin
AU - Zhang, Tian
AU - Wen, Xiaoming
AU - Xu, Bo
AU - Sun, Licheng
AU - Bach, Udo
AU - Cheng, Yi Bing
PY - 2018/9/12
Y1 - 2018/9/12
N2 - Chemical doping of organic semiconductors has been recognized as an effective way to enhance the electrical conductivity. In perovskite solar cells (PSCs), various types of dopants have been developed for organic hole transport materials (HTMs); however, the knowledge of the basic requirements for being efficient dopants as well as the comprehensive roles of the dopants in PSCs has not been clearly revealed. Here, three copper-based complexes with controlled redox activities are applied as dopants in PSCs, and it is found that the oxidative reactivity of dopants presents substantial impacts on conductivity, charge dynamics, and solar cell performance. A significant improvement of open-circuit voltage (V oc ) by more than 100 mV and an increase of power conversion efficiency from 13.2 to 19.3% have been achieved by tuning the doping level of the HTM. The observed large variation of V oc for three dopants reveals their different recombination kinetics at the perovskite/HTM interfaces and suggests a model of an interfacial recombination mechanism. We also suggest that the dopants in HTMs can also affect the charge recombination kinetics as well as the solar cell performance. Based on these findings, a strategy is proposed to physically passivate the electron-hole recombination by inserting an ultrathin Al 2 O 3 insulating layer between the perovskite and the HTM. This strategy contributes a significant enhancement of the power conversion efficiency and environmental stability, indicating that dopant engineering is one crucial way to further improve the performance of PSCs.
AB - Chemical doping of organic semiconductors has been recognized as an effective way to enhance the electrical conductivity. In perovskite solar cells (PSCs), various types of dopants have been developed for organic hole transport materials (HTMs); however, the knowledge of the basic requirements for being efficient dopants as well as the comprehensive roles of the dopants in PSCs has not been clearly revealed. Here, three copper-based complexes with controlled redox activities are applied as dopants in PSCs, and it is found that the oxidative reactivity of dopants presents substantial impacts on conductivity, charge dynamics, and solar cell performance. A significant improvement of open-circuit voltage (V oc ) by more than 100 mV and an increase of power conversion efficiency from 13.2 to 19.3% have been achieved by tuning the doping level of the HTM. The observed large variation of V oc for three dopants reveals their different recombination kinetics at the perovskite/HTM interfaces and suggests a model of an interfacial recombination mechanism. We also suggest that the dopants in HTMs can also affect the charge recombination kinetics as well as the solar cell performance. Based on these findings, a strategy is proposed to physically passivate the electron-hole recombination by inserting an ultrathin Al 2 O 3 insulating layer between the perovskite and the HTM. This strategy contributes a significant enhancement of the power conversion efficiency and environmental stability, indicating that dopant engineering is one crucial way to further improve the performance of PSCs.
KW - Al O
KW - chemical dopants
KW - hole transport materials
KW - interfacial recombination
KW - passivation
KW - perovskite solar cells
UR - http://www.scopus.com/inward/record.url?scp=85053682102&partnerID=8YFLogxK
U2 - 10.1021/acsnano.8b06062
DO - 10.1021/acsnano.8b06062
M3 - Article
VL - 12
SP - 10452
EP - 10462
JO - ACS Nano
JF - ACS Nano
SN - 1936-0851
IS - 10
ER -