|
1
|
Grover R, Srivastava R, Saxena K. Luminescence studies in cadmium telluride nanocrystals grown on glass substrates. RSC Adv 2022; 12:26596-26602. [PMID: 36275160 PMCID: PMC9487583 DOI: 10.1039/d2ra01387h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 08/10/2022] [Indexed: 11/25/2022] Open
Abstract
The thermal evaporation method can easily be employed to fabricate hybrid inorganic-organic LEDs and the emission properties can be controlled by varying the thickness of the nanocrystalline CdTe film. The fabrication of CdTe nanocrystals on glass substrates was demonstrated using a thermal evaporation method. Films were characterised using various experimental tools, such as SEM, TEM, AFM, UV-Vis and PL spectroscopy. The formation of nanoparticles with diameters from 1.5 nm up to 9 nm was observed in the nanocrystalline thin films. The organic light emitting diodes (OLEDs) based on these nanocrystals as an emissive layer exhibit electroluminescence (EL) in the green to yellow region of the visible spectrum, which is ascribed to the varying size dependent EL from the nanocrystals of CdTe present in the thin film. The method demonstrates an easy and convenient way to incorporate inorganic CdTe nanocrystals inside the organic light emitting devices.
Collapse
Affiliation(s)
- Rakhi Grover
- Amity Institute of Advanced Research and Studies (Materials and Devices) AIARS (M&D) & Amity Institute of Renewable and Alternative Energy AIRAE, Amity University Sector 125 Noida UP 201303 India
| | - Ritu Srivastava
- Advanced Materials and Device Metrology Division, Council of Scientific and Industrial Research-National Physical Laboratory (CSIR-NPL) Dr K. S. Krishnan Road New Delhi-110012 India
| | - Kanchan Saxena
- Amity Institute of Advanced Research and Studies (Materials and Devices) AIARS (M&D) & Amity Institute of Renewable and Alternative Energy AIRAE, Amity University Sector 125 Noida UP 201303 India
| |
Collapse
|
|
2
|
Xu A, Huang Q, Luo K, Qin D, Xu W, Wang D, Hou L. Efficient Nanocrystal Photovoltaics with PTAA as Hole Transport Layer. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3067. [PMID: 36080104 PMCID: PMC9458081 DOI: 10.3390/nano12173067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/31/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
The power conversion efficiency (PCE) of solution-processed CdTe nanocrystals (NCs) solar cells has been significantly promoted in recent years due to the optimization of device design by advanced interface engineering techniques. However, further development of CdTe NC solar cells is still limited by the low open-circuit voltage (Voc) (mostly in range of 0.5-0.7 V), which is mainly attributed to the charge recombination at the CdTe/electrode interface. Herein, we demonstrate a high-efficiency CdTe NCs solar cell by using organic polymer poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) as the hole transport layer (HTL) to decrease the interface recombination and enhance the Voc. The solar cell with the architecture of ITO/ZnO/CdS/CdSe/CdTe/PTAA/Au was fabricated via a layer-by-layer solution process. Experimental results show that PTAA offers better back contact for reducing interface resistance than the device without HTL. It is found that a dipole layer is produced between the CdTe NC thin film and the back contact electrode; thus the built-in electric field (Vbi) is reinforced, allowing more efficient carrier separation. By introducing the PTAA HTL in the device, the open-circuit voltage, short-circuit current density and the fill factor are simultaneously improved, leading to a high PCE of 6.95%, which is increased by 30% compared to that of the control device without HTL (5.3%). This work suggests that the widely used PTAA is preferred as the excellent HTL for achieving highly efficient CdTe NC solar cells.
Collapse
Affiliation(s)
- Ao Xu
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
| | - Qichuan Huang
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
| | - Kaiying Luo
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
| | - Donghuan Qin
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
| | - Wei Xu
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
| | - Dan Wang
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
| | - Lintao Hou
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Siyuan Laboratory, Department of Physics, Jinan University, Guangzhou 510632, China
| |
Collapse
|
|
3
|
Hou M, Zhou Z, Xu A, Xiao K, Li J, Qin D, Xu W, Hou L. Synthesis of Group II-VI Semiconductor Nanocrystals via Phosphine Free Method and Their Application in Solution Processed Photovoltaic Devices. NANOMATERIALS 2021; 11:nano11082071. [PMID: 34443902 PMCID: PMC8399757 DOI: 10.3390/nano11082071] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/10/2021] [Accepted: 08/11/2021] [Indexed: 11/16/2022]
Abstract
Solution-processed CdTe semiconductor nanocrystals (NCs) have exhibited astonishing potential in fabricating low-cost, low materials consumption and highly efficient photovoltaic devices. However, most of the conventional CdTe NCs reported are synthesized through high temperature microemulsion method with high toxic trioctylphosphine tellurite (TOP-Te) or tributylphosphine tellurite (TBP-Te) as tellurium precursor. These hazardous substances used in the fabrication process of CdTe NCs are drawing them back from further application. Herein, we report a phosphine-free method for synthesizing group II-VI semiconductor NCs with alkyl amine and alkyl acid as ligands. Based on various characterizations like UV-vis absorption (UV), transmission electron microscope (TEM), and X-ray diffraction (XRD), among others, the properties of the as-synthesized CdS, CdSe, and CdTe NCs are determined. High-quality semiconductor NCs with easily controlled size and morphology could be fabricated through this phosphine-free method. To further investigate its potential to industrial application, NCs solar cells with device configuration of ITO/ZnO/CdSe/CdTe/Au and ITO/ZnO/CdS/CdTe/Au are fabricated based on NCs synthesized by this method. By optimizing the device fabrication conditions, the champion device exhibited power conversion efficiency (PCE) of 2.28%. This research paves the way for industrial production of low-cost and environmentally friendly NCs photovoltaic devices.
Collapse
Affiliation(s)
- Mingyue Hou
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (M.H.); (Z.Z.); (A.X.); (K.X.); (J.L.)
| | - Zhaohua Zhou
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (M.H.); (Z.Z.); (A.X.); (K.X.); (J.L.)
| | - Ao Xu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (M.H.); (Z.Z.); (A.X.); (K.X.); (J.L.)
| | - Kening Xiao
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (M.H.); (Z.Z.); (A.X.); (K.X.); (J.L.)
| | - Jiakun Li
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (M.H.); (Z.Z.); (A.X.); (K.X.); (J.L.)
| | - Donghuan Qin
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (M.H.); (Z.Z.); (A.X.); (K.X.); (J.L.)
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
- Correspondence: (D.Q.); (W.X.); (L.H.)
| | - Wei Xu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (M.H.); (Z.Z.); (A.X.); (K.X.); (J.L.)
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
- Correspondence: (D.Q.); (W.X.); (L.H.)
| | - Lintao Hou
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Siyuan Laboratory, Department of Physics, Jinan University, Guangzhou 510632, China
- Correspondence: (D.Q.); (W.X.); (L.H.)
| |
Collapse
|
|
4
|
Efficient PbS Quantum Dot Solar Cells with Both Mg-Doped ZnO Window Layer and ZnO Nanocrystal Interface Passivation Layer. NANOMATERIALS 2021; 11:nano11010219. [PMID: 33467785 PMCID: PMC7830923 DOI: 10.3390/nano11010219] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 11/16/2022]
Abstract
In this paper, a Mg-doped ZnO (MZO) thin film is prepared by a simple solution process under ambient conditions and is used as the window layer for PbS solar cells due to a wide n-type bandgap. Moreover, a thin layer of ZnO nanocrystals (NCs) was deposited on the MZO to reduce carrier recombination at the interface for inverted PbS quantum dot solar cells with the configuration Indium Tin Oxides (ITO)/MZO/ZnO NC (w/o)/PbS/Au. The effect of film thickness and annealing temperature of MZO and ZnO NC on the performance of PbS quantum dot solar cells was investigated in detail. It was found that without the ZnO NC thin layer, the highest power conversion efficiency(PCE) of 5.52% was obtained in the case of a device with an MZO thickness of 50 nm. When a thin layer of ZnO NC was introduced between MZO and PbS quantum dot film, the PCE of the champion device was greatly improved to 7.06% due to the decreased interface recombination. The usage of the MZO buffer layer along with the ZnO NC interface passivation technique is expected to further improve the performance of quantum dot solar cells.
Collapse
|
|
5
|
Jiang Y, Pan Y, Wu W, Luo K, Rong Z, Xie S, Zuo W, Yu J, Zhang R, Qin D, Xu W, Wang D, Hou L. Hole Transfer Layer Engineering for CdTe Nanocrystal Photovoltaics with Improved Efficiency. NANOMATERIALS 2020; 10:nano10071348. [PMID: 32664220 PMCID: PMC7407640 DOI: 10.3390/nano10071348] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 06/28/2020] [Accepted: 07/04/2020] [Indexed: 11/17/2022]
Abstract
Interface engineering has led to significant progress in solution-processed CdTe nanocrystal (NC) solar cells in recent years. High performance solar cells can be fabricated by introducing a hole transfer layer (HTL) between CdTe and a back contact electrode to reduce carrier recombination by forming interfacial dipole effect at the interface. Here, we report the usage of a commercial product 2,2′,7,7′-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (Spiro) as a hole transfer layer to facilitate the hole collecting for CdTe nanocrystal solar cells. It is found that heat treatment on the hole transfer layer has significant influence on the NC solar cells performance. The Jsc, Voc, and power conversion efficiency (PCE) of NC solar cells are simultaneously increased due to the decreased contact resistance and enhanced built-in electric field. We demonstrate solar cells that achieve a high PCE of 8.34% for solution-processed CdTe NC solar cells with an inverted structure by further optimizing the HTL annealing temperature, which is among the highest value in CdTe NC solar cells with the inverted structure.
Collapse
Affiliation(s)
- Yasi Jiang
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Yiyang Pan
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Wanhua Wu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Kaiying Luo
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Zhitao Rong
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Sihang Xie
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Wencai Zuo
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Jingya Yu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Ruibo Zhang
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
| | - Donghuan Qin
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
- Correspondence: (D.Q.); (L.H.); Tel.: +86-020-8711-4346 (D.Q.); +86-020-8522-4386 (L.H.)
| | - Wei Xu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
| | - Dan Wang
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; (Y.J.); (Y.P.); (W.W.); (K.L.); (Z.R.); (S.X.); (W.Z.); (J.Y.); (R.Z.); (W.X.); (D.W.)
- State Key Laboratory of Luminescent Materials & Devices, Institute of Polymer Optoelectronic Materials & Devices, South China University of Technology, Guangzhou 510640, China
| | - Lintao Hou
- Siyuan Laboratory, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Department of Physics, Jinan University, Guangzhou 510632, China
- Correspondence: (D.Q.); (L.H.); Tel.: +86-020-8711-4346 (D.Q.); +86-020-8522-4386 (L.H.)
| |
Collapse
|
|
6
|
Abstract
The use of solution-processed photovoltaics is a low cost, low material-consuming way to harvest abundant solar energy. Organic semiconductors based on perovskite or colloidal quantum dot photovoltaics have been well developed in recent years; however, stability is still an important issue for these photovoltaic devices. By combining solution processing, chemical treatment, and sintering technology, compact and efficient CdTe nanocrystal (NC) solar cells can be fabricated with high stability by optimizing the architecture of devices. Here, we review the progress on solution-processed CdTe NC-based photovoltaics. We focus particularly on NC materials and the design of devices that provide a good p–n junction quality, a graded bandgap for extending the spectrum response, and interface engineering to decrease carrier recombination. We summarize the progress in this field and give some insight into device processing, including element doping, new hole transport material application, and the design of new devices.
Collapse
|
|
7
|
The Effects of ZnTe:Cu Back Contact on the Performance of CdTe Nanocrystal Solar Cells with Inverted Structure. NANOMATERIALS 2019; 9:nano9040626. [PMID: 30999645 PMCID: PMC6523567 DOI: 10.3390/nano9040626] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 04/08/2019] [Accepted: 04/12/2019] [Indexed: 11/16/2022]
Abstract
CdTe nanocrystal (NC) solar cells have received much attention in recent years due to their low cost and environmentally friendly fabrication process. Nowadays, the back contact is still the key issue for further improving device performance. It is well known that, in the case of CdTe thin-film solar cells prepared with the close-spaced sublimation (CSS) method, Cu-doped CdTe can drastically decrease the series resistance of CdTe solar cells and result in high device performance. However, there are still few reports on solution-processed CdTe NC solar cells with Cu-doped back contact. In this work, ZnTe:Cu or Cu:Au back contact layer (buffer layer) was deposited on the CdTe NC thin film by thermal evaporation and devices with inverted structure of ITO/ZnO/CdSe/CdTe/ZnTe:Cu (or Cu)/Au were fabricated and investigated. It was found that, comparing to an Au or Cu:Au device, the incorporation of ZnTe:Cu as a back contact layer can improve the open circuit voltage (Voc) and fill factor (FF) due to an optimized band alignment, which results in enhanced power conversion efficiency (PCE). By carefully optimizing the treatment of the ZnTe:Cu film (altering the film thickness and annealing temperature), an excellent PCE of 6.38% was obtained, which showed a 21.06% improvement compared with a device without ZnTe:Cu layer (with a device structure of ITO/ZnO/CdSe/CdTe/Au).
Collapse
|
|
8
|
Mei X, Wu B, Guo X, Liu X, Rong Z, Liu S, Chen Y, Qin D, Xu W, Hou L, Chen B. Efficient CdTe Nanocrystal/TiO₂ Hetero-Junction Solar Cells with Open Circuit Voltage Breaking 0.8 V by Incorporating A Thin Layer of CdS Nanocrystal. NANOMATERIALS (BASEL, SWITZERLAND) 2018; 8:E614. [PMID: 30104543 PMCID: PMC6116231 DOI: 10.3390/nano8080614] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 08/10/2018] [Accepted: 08/10/2018] [Indexed: 11/18/2022]
Abstract
Nanocrystal solar cells (NCs) allow for large scale solution processing under ambient conditions, permitting a promising approach for low-cost photovoltaic products. Although an up to 10% power conversion efficiency (PCE) has been realized with the development of device fabrication technologies, the open circuit voltage (Voc) of CdTe NC solar cells has stagnated below 0.7 V, which is significantly lower than most CdTe thin film solar cells fabricated by vacuum technology (around 0.8 V~0.9 V). To further improve the NC solar cells' performance, an enhancement in the Voc towards 0.8⁻1.0 V is urgently required. Given the unique processing technologies and physical properties in CdTe NC, the design of an optimized band alignment and improved junction quality are important issues to obtain efficient solar cells coupled with high Voc. In this work, an efficient method was developed to improve the performance and Voc of solution-processed CdTe nanocrystal/TiO₂ hetero-junction solar cells. A thin layer of solution-processed CdS NC film (~5 nm) as introduced into CdTe NC/TiO₂ to construct hetero-junction solar cells with an optimized band alignment and p-n junction quality, which resulted in a low dark current density and reduced carrier recombination. As a result, devices with improved performance (5.16% compared to 2.63% for the control device) and a Voc as high as 0.83 V were obtained; this Voc value is a record for a solution-processed CdTe NC solar cell.
Collapse
Affiliation(s)
- Xianglin Mei
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Bin Wu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Xiuzhen Guo
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Xiaolin Liu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Zhitao Rong
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Songwei Liu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Yanru Chen
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Donghuan Qin
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
- Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices, South China University of Technology, Guangzhou 510640, China.
| | - Wei Xu
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
- Institute of Polymer Optoelectronic Materials & Devices, State Key Laboratory of Luminescent Materials & Devices, South China University of Technology, Guangzhou 510640, China.
| | - Lintao Hou
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials, Siyuan Laboratory, Department of Physics, Jinan University, Guangzhou 510632, China.
| | - Bingchang Chen
- School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
| |
Collapse
|
|
9
|
Solution-Processed CdTe Thin-Film Solar Cells Using ZnSe Nanocrystal as a Buffer Layer. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8071195] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The CdTe nanocrystal (NC) is an outstanding, low-cost photovoltaic material for highly efficient solution-processed thin-film solar cells. Currently, most CdTe NC thin-film solar cells are based on CdSe, ZnO, or CdS buffer layers. In this study, a wide bandgap and Cd-free ZnSe NC is introduced for the first time as the buffer layer for all solution-processed CdTe/ZnSe NC hetero-junction thin-film solar cells with a configuration of ITO/ZnO/ZnSe/CdTe/MoOx/Au. The dependence of the thickness of the ZnSe NC film, the annealing temperature and the chemical treatment on the performance of NC solar cells are investigated and discussed in detail. We further develop a ligand-exchanging strategy that involves 1,2-ethanedithiol (EDT) during the fabrication of ZnSe NC film. An improved power conversion efficiency (PCE) of 3.58% is obtained, which is increased by 16.6% when compared to a device without the EDT treatment. We believe that using ZnSe NC as the buffer layer holds the potential for developing high-efficiency, low cost, and stable CdTe NC-based solar cells.
Collapse
|