Aluminum and Molybdenum Co-Doped Zinc Oxide Films as Dual-Functional Carrier-Selective Contact for Silicon Solar Cells
Zhiyuan XuXiaoning LiuJiakai ZhouYu YanYaya SongQian HuangHuizhi RenYi DingXiaodan ZhangYing ZhaoGuofu Hou
6
Citation
34
Reference
10
Related Paper
Citation Trend
Abstract:
Aluminum-doped zinc oxide (AZO) is considered as a promising candidate as transparent conductive oxide (TCO) for silicon heterojunction solar cells due to its high carrier density, nontoxic nature, and low cost. Herein, it is presented that the transparency of the AZO film can be optimized through co-sputtering of AZO and molybdenum oxide (MoOx). Furthermore, aluminum and molybdenum co-doped zinc oxide (MAZO) can be used as both the TCO layer and electron-selective contact (ESC) for silicon heterojunction solar cells. The surface morphology, cation oxidation state, and optical and electrical properties of all MAZO films are characterized. It is found that the transmittance of all MAZO films is significantly increased at a wavelength of 450-800 nm due to MAZO with a stronger Zn-O bond and a wider band gap. The conductivity of MAZO films is approximate to AZO films at a low MoOx target deposit power (50 W), and the sheet resistance of MAZO films increases significantly by increasing the deposition power up to 100 W. Finally, the optimized MAZO films are used as TCO and ESC for silicon heterojunction solar cells, showing a power conversion efficiency of 19.58%. The results show an effective stage to improve the optical properties of AZO through co-doping and the possibility of applying MAZO as a dual-functional layer for silicon solar cells.The development of low bandgap conducting polymers has made bulk heterojunction solar cells a viable low cost renewable energy source. The high boiling point of 1,8-diiodooctane (DIO) is usually used to control the morphology of the active layer consisting of a conducting polymer and PCBM, so that a high power conversion solar cell can be achieved. We report here an alternative approach using nonvolatile, crystalline and conducting P3HT as an effective morphology control agent. A model system of PCPDTBT/PC61BM was selected for this study. The change of optoelectronic properties with the introduction of P3HT was monitored by measuring the absorption spectra and charge carrier mobility, and the morphology change with the introduction of P3HT in the active layer was monitored by AFM, TEM, and GIXRD. The results indicate that favorable bi-continuous phase separation and appropriate domain size of each phase can be achieved to facilitate fast charge transport, and thus improve the power conversion efficiency of the solar cell. By adding 1 wt% P3HT into the blend of PCPDTBT/PC61BM, the power conversion efficiency can be improved by 20%. Moreover, with the incorporation of 1 wt% P3HT to the blend of PCPDTBT/PC61BM with DIO, the power conversion efficiency can be further increased by 17%. The strategy of this study can be expanded to other low bandgap conducting polymers for high efficiency bulk heterojunction solar cells.
Active layer
Hybrid solar cell
Charge carrier
Cite
Citations (47)
Quantum Efficiency
Cite
Citations (32)
The photovoltaic properties of bulk heterojunction solar cells using indene-C60 bisadduct (ICBA) as the electron acceptor were investigated by using three donor–acceptor copolymers (PSEHTT, PSOTT, and PSOxTT) in comparison with PC61BM-based solar cells. The open circuit voltage of the copolymer:ICBA devices was 0.82–0.92 V, which is 0.25 V enhanced compared to the copolymer:PCBM solar cells. Compared to PCBM-based solar cells, the photocurrent density of ICBA-based devices was significantly increased in the case of PSEHTT but decreased in PSOTT and PSOxTT. This variation of photocurrent density with the copolymer structure was correlated with the charge photogeneration efficiency as determined by transient absorption spectroscopy. A power conversion efficiency of 5.4% was achieved in PSEHTT:ICBA solar cells, which represents a 50% enhancement in efficiency compared to PC61BM devices. Our results demonstrate that ICBA can significantly increase the open circuit voltage, current density, and power conversion efficiency of donor–acceptor copolymer-based BHJ solar cells.
Open-circuit voltage
Photocurrent
Acceptor
Electron acceptor
Cite
Citations (103)
Cite
Citations (11)
Component (thermodynamics)
Transient (computer programming)
Cite
Citations (4)
Crystal (programming language)
Cite
Citations (0)
Open-circuit voltage
Acceptor
Cite
Citations (8)
Two medium-bandgap polymers composed of benzo[1,2-b:4,5-b']dithiohpene and 2,1,3-benzothiadiazole with 6-octyl-thieno[3,2-b]thiophene as a π-bridge unit are synthesized and their photovoltaic properties are analyzed. The two polymers have deep highest occupied molecular orbital energy levels, high crystallinity, optimal bulk-heterojunction morphology, and efficient charge transport, resulting in a power conversion efficiency of as high as 9.44% for a single-junction polymer solar-cell device.
Hybrid solar cell
HOMO/LUMO
Cite
Citations (90)
Active layer
HOMO/LUMO
Open-circuit voltage
Cite
Citations (15)
The photovoltaic performance of polymer bulk heterojunction solar cells is studied systematically. Using a new benzodithiophene polymer (PTB7) and PC71BM (see figure) a power conversion efficiency of 7.4% has been achieved in PTB7/PC71BM-blend film, indicating a great potential and bright future for polymer solar cells (FF = fill factor, PCE ;= power-conversion efficiency). Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Cite
Citations (3,602)