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Gour KS, Pawar PS, Lee M, Karade VC, Yun JS, Heo J, Park J, Yun JH, Kim JH. Fostering Charge Carrier Transport and Absorber Growth Properties in CZTSSe Thin Films with an ALD-SnO 2 Capping Layer. ACS APPLIED MATERIALS & INTERFACES 2024; 16:30010-30019. [PMID: 38814930 DOI: 10.1021/acsami.4c02432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
The present study demonstrates that precursor passivation is an effective approach for improving the crystallization process and controlling the detrimental defect density in high-efficiency Cu2ZnSn(S,Se)4 (CZTSSe) thin films. It is achieved by applying the atomic layer deposition (ALD) of the tin oxide (ALD-SnO2) capping layer onto the precursor (Cu-Zn-Sn) thin films. The ALD-SnO2 capping layer was observed to facilitate the homogeneous growth of crystalline grains and mitigate defects prior to sulfo-selenization in CZTSSe thin films. Particularly, the CuZn and SnZn defects and deep defects associated with Sn were effectively mitigated due to the reduction of Sn2+ and the increase in Sn4+ levels in the kesterite CZTSSe film after introducing ALD-SnO2 on the precursor films. Subsequently, devices integrating the ALD-SnO2 layer exhibited significantly reduced recombination and efficient charge transport at the heterojunction interface and within the bulk CZTSSe absorber bulk properties. Finally, the CZTSSe device showed improved power conversion efficiency (PCE) from 8.46% to 10.1%. The incorporation of ALD-SnO2 revealed reduced defect sites, grain boundaries, and surface roughness, improving the performance. This study offers a systematic examination of the correlation between the incorporation of the ALD-SnO2 layer and the improved PCE of CZTSSe thin film solar cells (TFSCs), in addition to innovative approaches for improving absorber quality and defect control to advance the performance of kesterite CZTSSe devices.
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Affiliation(s)
- Kuldeep Singh Gour
- Surface Engineering Group, Advanced Materials & Processes Division,CSIR-National Metallurgical Laboratory, Jamshedpur 831007, India
- Department of Energy Engineering, Korea Institute of Energy Technology (KENTECH), Naju, Jeonnam 58217, Republic of Korea
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Pravin S Pawar
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Minwoo Lee
- Australian Centre for Advanced Photovoltaics (ACAP), School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney, NSW 2052, Australia
| | - Vijay C Karade
- Wright Center for Photovoltaic Innovation and Commercialization, Department of Physics and Astronomy, University of Toledo, Toledo, Ohio 43606, United States
| | - Jae Sung Yun
- Australian Centre for Advanced Photovoltaics (ACAP), School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney, NSW 2052, Australia
- Department of Electrical and Electronic Engineering, Advanced Technology Institute (ATI), University of Surrey, Guildford, Surrey GU2 7XH, United Kingdom
| | - Jaeyeong Heo
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jongsung Park
- Department of Energy Engineering, Gyeongsang National University (GNU), Jinju, Gyeongnam 52849, Republic of Korea
| | - Jae Ho Yun
- Department of Energy Engineering, Korea Institute of Energy Technology (KENTECH), Naju, Jeonnam 58217, Republic of Korea
| | - Jin Hyeok Kim
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, Republic of Korea
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Wang J, Shi J, Yin K, Meng F, Wang S, Lou L, Zhou J, Xu X, Wu H, Luo Y, Li D, Chen S, Meng Q. Pd(II)/Pd(IV) redox shuttle to suppress vacancy defects at grain boundaries for efficient kesterite solar cells. Nat Commun 2024; 15:4344. [PMID: 38773145 PMCID: PMC11109278 DOI: 10.1038/s41467-024-48850-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 05/13/2024] [Indexed: 05/23/2024] Open
Abstract
Charge loss at grain boundaries of kesterite Cu2ZnSn(S, Se)4 polycrystalline absorbers is an important cause limiting the performance of this emerging thin-film solar cell. Herein, we report a Pd element assisted reaction strategy to suppress atomic vacancy defects in GB regions. The Pd, on one hand in the form of PdSex compounds, can heterogeneously cover the GBs of the absorber film, suppressing Sn and Se volatilization loss and the formation of their vacancy defects (i.e. VSn and VSe), and on the other hand, in the form of Pd(II)/Pd(IV) redox shuttle, can assist the capture and exchange of Se atoms, thus contributing to eliminating the already-existing VSe defects within GBs. These collective effects have effectively reduced charge recombination loss and enhanced p-type characteristics of the kesterite absorber. As a result, high-performance kesterite solar cells with a total-area efficiency of 14.5% (certified at 14.3%) have been achieved.
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Affiliation(s)
- Jinlin Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Jiangjian Shi
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China
| | - Kang Yin
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Fanqi Meng
- School of Materials Science and Engineering, Peking University, Beijing, 100871, P. R. China
| | - Shanshan Wang
- School of Microelectronics, Fudan University, Shanghai, 200433, P. R. China
| | - Licheng Lou
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Jiazheng Zhou
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Xiao Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Huijue Wu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China
| | - Yanhong Luo
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- Songshan Lake Materials Laboratory, Dongguan, 523808, P. R. China
| | - Dongmei Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
- Songshan Lake Materials Laboratory, Dongguan, 523808, P. R. China.
| | - Shiyou Chen
- School of Microelectronics, Fudan University, Shanghai, 200433, P. R. China.
| | - Qingbo Meng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences (CAS), Beijing, 100190, P. R. China.
- Songshan Lake Materials Laboratory, Dongguan, 523808, P. R. China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
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3
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Park SW, He M, Jang JS, Kamble GU, Suryawanshi UP, Baek MC, Suryawanshi MP, Gang MG, Park Y, Choi HJ, Hao X, Shin SW, Kim JH. Facile Approach for Metallic Precursor Engineering for Efficient Kesterite Thin-Film Solar Cells. ACS APPLIED MATERIALS & INTERFACES 2024; 16:16328-16339. [PMID: 38516946 DOI: 10.1021/acsami.4c01230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Kesterite-based Cu2ZnSn(S,Se)4 (CZTSSe) thin-film solar cells (TFSCs) are a promising candidate for low-cost, clean energy production owing to their environmental friendliness and the earth-abundant nature of their constituents. However, the advancement of kesterite TFSCs has been impeded by abundant defects and poor microstructure, limiting their performance potential. In this study, we present efficient Ag-alloyed CZTSSe TFSCs enabled by a facile metallic precursor engineering approach. The positioning of the Ag nanolayer in the metallic stacked precursor proves crucial in expediting the formation of Cu-Sn metal alloys during the alloying process. Specifically, Ag-included metallic precursors promote the growth of larger grains and a denser microstructure in CZTSSe thin films compared to those without Ag. Moreover, the improved uniformity of Ag, facilitated by the evaporation deposition technique, significantly suppresses the formation of detrimental defects and related defect clusters. This suppression effectively reduces nonradiative recombination, resulting in enhanced performance in kesterite TFSCs. This study not only introduces a metallic precursor engineering strategy for efficient kesterite-based TFSCs but also accelerates the development of microstructure evolution from metallic stacked precursors to metal chalcogenide compounds.
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Affiliation(s)
- Sang Woo Park
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, South Korea
| | - Mingrui He
- School of Photovoltaic and Renewable Energy Engineering, UNSW Sydney, New South Wales 2052, Australia
| | - Jun Sung Jang
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, South Korea
| | - Girish U Kamble
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, South Korea
| | - Umesh P Suryawanshi
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, South Korea
| | - Myeong Cheol Baek
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, South Korea
| | - Mahesh P Suryawanshi
- School of Photovoltaic and Renewable Energy Engineering, UNSW Sydney, New South Wales 2052, Australia
| | - Myeng Gil Gang
- SCOTRA Corporation, R&D Center, Seoul 05855, South Korea
| | - Youseong Park
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, South Korea
| | - Ho Jun Choi
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, South Korea
| | - Xiaojing Hao
- School of Photovoltaic and Renewable Energy Engineering, UNSW Sydney, New South Wales 2052, Australia
| | - Seung Wook Shin
- Future Agricultural Research Division, Rural Research Institute, Korea Rural Community Corporation, Ansan-si 15634, South Korea
| | - Jin Hyeok Kim
- Optoelectronics Convergence Research Center and Department of Materials Science and Engineering, Chonnam National University, Gwangju 61186, South Korea
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Korade SD, Gour KS, Karade VC, Jang JS, Rehan M, Patil SS, Bhat TS, Patil AP, Yun JH, Park J, Kim JH, Patil PS. Improving the Device Performance of CZTSSe Thin-Film Solar Cells via Indium Doping. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 38047907 DOI: 10.1021/acsami.3c13813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Cation incorporation emerges as a promising approach for improving the performance of the kesterite Cu2ZnSn(S,Se)4 (CZTSSe) device. Herein, we report indium (In) doping using the chemical bath deposition (CBD) technique to enhance the optoelectronic properties of CZTSSe thin-film solar cells (TFSCs). To incorporate a small amount of the In element into the CZTSSe absorber thin films, an ultrathin (<10 nm) layer of In2S3 is deposited on soft-annealed precursor (Zn-Sn-Cu) thin films prior to the sulfo-selenization process. The successful doping of In improved crystal growth and promoted the formation of larger grains. Furthermore, the CZTSSe TFSCs fabricated with In doping exhibited improved device performance. In particular, the In-CZTSSe-2-based device showed an improved power conversion efficiency (PCE) of 9.53%, open-circuit voltage (Voc) of 486 mV, and fill factor (FF) of 61% compared to the undoped device. Moreover, the small amount of In incorporated into the CZTSSe absorber demonstrated reduced nonradiative recombination, improved carrier separation, and enhanced carrier transport properties. This study suggests a simple and effective way to incorporate In to achieve high efficiency and low Voc loss.
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Affiliation(s)
- Sumit D Korade
- Thin Film Materials Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, Maharashtra, India
- Optoelectronics Convergence Research Center and Department of Materials Science & Engineering, Chonnam National University, Gwangju 61186, Republic of Korea
- Department of Physics, Kisan Veer Mahavidyalaya, Wai 412803, Maharashtra, India
| | - Kuldeep Singh Gour
- Surface Engineering Group, Advanced Materials & Processes Division, CSIR-National Metallurgical Laboratory, Jamshedpur 831007, Jharkhand, India
| | - Vijay C Karade
- Department of Energy Engineering, Korea Institute of Energy Technology (KENTECH), Naju, Jeonnam 58217, Republic of Korea
| | - Jun Sung Jang
- Optoelectronics Convergence Research Center and Department of Materials Science & Engineering, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Muhammad Rehan
- Photovoltaics Research Department, Korea Institute of Energy Research (KIER), 152-Gajeong-ro, Yuseong-gu, Daejeon 34129, Republic of Korea
| | - Satyajeet S Patil
- Thin Film Materials Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, Maharashtra, India
| | - Tejasvinee S Bhat
- School of Nanoscience and Biotechnology, Shivaji University, Kolhapur 416004, Maharashtra, India
| | - Akhilesh P Patil
- School of Nanoscience and Biotechnology, Shivaji University, Kolhapur 416004, Maharashtra, India
| | - Jae Ho Yun
- Department of Energy Engineering, Korea Institute of Energy Technology (KENTECH), Naju, Jeonnam 58217, Republic of Korea
| | - Jongsung Park
- Department of Energy Engineering, Gyeongsang National University, Jinju, Gyeongnam 52849, Republic of Korea
| | - Jin Hyeok Kim
- Optoelectronics Convergence Research Center and Department of Materials Science & Engineering, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Pramod S Patil
- Thin Film Materials Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, Maharashtra, India
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Rodriguez-Osorio KG, Morán-Lázaro JP, Ojeda-Martínez M, Montoya De Los Santos I, Ouarie NE, Feddi EM, Pérez LM, Laroze D, Routray S, Sánchez-Rodríguez FJ, Courel M. Analytical Modeling and Optimization of Cu 2ZnSn(S,Se) 4 Solar Cells with the Use of Quantum Wells under the Radiative Limit. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2058. [PMID: 37513069 PMCID: PMC10384985 DOI: 10.3390/nano13142058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/04/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023]
Abstract
In this work, we present a theoretical study on the use of Cu2ZnSn(S,Se)4 quantum wells in Cu2ZnSnS4 solar cells to enhance device efficiency. The role of different well thickness, number, and S/(S + Se) composition values is evaluated. The physical mechanisms governing the optoelectronic parameters are analyzed. The behavior of solar cells based on Cu2ZnSn(S,Se)4 without quantum wells is also considered for comparison. Cu2ZnSn(S,Se)4 quantum wells with a thickness lower than 50 nm present the formation of discretized eigenstates which play a fundamental role in absorption and recombination processes. Results show that well thickness plays a more important role than well number. We found that the use of wells with thicknesses higher than 20 nm allow for better efficiencies than those obtained for a device without nanostructures. A record efficiency of 37.5% is achieved when 36 wells with a width of 50 nm are used, considering an S/(S + Se) well compositional ratio of 0.25.
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Affiliation(s)
- Karina G Rodriguez-Osorio
- Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca C.P. 46600, Jalisco, Mexico
| | - Juan P Morán-Lázaro
- Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca C.P. 46600, Jalisco, Mexico
| | - Miguel Ojeda-Martínez
- Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca C.P. 46600, Jalisco, Mexico
| | - Isaac Montoya De Los Santos
- Instituto de Estudios de la Energía, Universidad del Istmo, Santo Domingo Tehuantepec C.P. 70760, Oaxaca, Mexico
| | - Nassima El Ouarie
- Group of Optoelectronic of Semiconductors and Nanomaterials, ENSAM, Mohammed V University in Rabat, Rabat 10100, Morocco
| | - El Mustapha Feddi
- Group of Optoelectronic of Semiconductors and Nanomaterials, ENSAM, Mohammed V University in Rabat, Rabat 10100, Morocco
- Institute of Applied Physics, Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, Ben Guerir 43150, Morocco
| | - Laura M Pérez
- Departamento de Física, FACI, Universidad de Tarapacá, Casilla 7D, Arica 1000000, Chile
| | - David Laroze
- Instituto de Alta Investigación, Universidad de Tarapacá, Casilla 7D, Arica 1000000, Chile
| | - Soumyaranjan Routray
- Department of Electronics and Communication Engineering, SRM Institute of Science and Technology, Chennai 603203, India
| | | | - Maykel Courel
- Centro Universitario de los Valles, Universidad de Guadalajara, Carretera Guadalajara-Ameca Km. 45.5, Ameca C.P. 46600, Jalisco, Mexico
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6
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Probing the depth inhomogeneity of spray pyrolyzed CZTS thin films via chemical etching. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2022.109952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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7
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Heidariramsheh M, Forouzandeh M, Taghavinia N, Mahdavi SM. Effect of Zn/Sn Ratio on Perovskite Solar Cell Performance Applying Off-Stoichiometric Cu 2ZnSnS 4/Carbon Hole-Collecting Electrodes. ACS APPLIED MATERIALS & INTERFACES 2022; 14:17296-17311. [PMID: 35380777 DOI: 10.1021/acsami.2c00206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Low-cost inorganic hole-transporting materials (HTMs) accompanied by a printable carbon electrode is an efficient approach to address the limitation of material cost of perovskite solar cells (PSCs) and get this technology closer to commercialization. The present work is focused on optimizing the Zn/Sn ratio of Cu2ZnSnS4/carbon hole collectors in n-i-p structured PSCs, where CuInS2/carbon is applied as the reference hole collector. This composition regulation is a solution to address the challenge of composition-related defects of the Cu2ZnSnS4 (CZTS) material. The Zn/Sn ratio was tuned by the initial proportion of the zinc precursor during the nanoparticle (NP) synthesis using a heating-up procedure. It was found that the enhancement of the Zn/Sn ratio leads to a gradual increase of the optical band gap. More importantly, an increased density of B-type defect clusters [2ZnCu + ZnSn] is confirmed using Raman results. Additionally, results from the cyclic voltammetry measurement show that by increasing the Zn/Sn value, the highest occupied molecular orbital (HOMO) of HTM is pulled down. These data match the upward trend of photovoltage. CZTS HTM with an optimal Zn/Sn ratio of 1.5 has a compatible energy level, along with the features of uniform and smooth coverage. The best efficiency of about 14.86% was obtained for optimal CZTS/carbon-based PSCs, which reaches from 14.86 to 15.49% after 25 days of aging.
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Affiliation(s)
- Maryam Heidariramsheh
- Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran 14588-89694, Iran
| | - Mozhdeh Forouzandeh
- Department of Physics, Sharif University of Technology, Tehran 11365-9161, Iran
| | - Nima Taghavinia
- Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran 14588-89694, Iran
- Department of Physics, Sharif University of Technology, Tehran 11365-9161, Iran
| | - Seyed Mohammad Mahdavi
- Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran 14588-89694, Iran
- Department of Physics, Sharif University of Technology, Tehran 11365-9161, Iran
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Liu J, Liu Z, Gao K, Cai H, Liu Y, Zhao W, Liu X, Cheng K, Du Z. Back Shallow Ge Gradient Enhanced Carrier Separation for CZTSe Solar Cells through a Coselenization Process. ACS APPLIED MATERIALS & INTERFACES 2021; 13:56302-56308. [PMID: 34788530 DOI: 10.1021/acsami.1c16861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Given the prominent success of the Ga gradient in CuIn1-xGaxSe2 (CIGSe) solar cells, Ge gradient implementation is a promising way to boost Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. However, Ge-graded CZTSSe solar cells only possess a low efficiency of 9.2%, far from that of Ge-incorporated CZTSSe without a gradient (12.3%). Herein, we demonstrated a shallow Ge gradient CZTSe solar cell with an improved efficiency over 10%. The Ge gradient was achieved through a GeSe2-Se coselenization process, where GeSe2 acts as a low-temperature fluxing agent to assist crystallization and induce Ge transport toward the back interface. The relieved band tails and improved junction quality, leading to a better carrier separation, were found to take a primary responsibility for device improvement. These results highlight a remarkable breakthrough for Ge-graded CZTSe solar cells and offer a promising way to develop Ge-involved solar cells.
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Affiliation(s)
- Jingling Liu
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
| | - Zhiwen Liu
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
| | - Kang Gao
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
| | - Hang Cai
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
| | - Yongjun Liu
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
| | - Weiqiang Zhao
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
| | - Xinsheng Liu
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
| | - Ke Cheng
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
| | - Zuliang Du
- Key Laboratory for Special Functional Materials of Ministry of Education, Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, Henan Province, People's Republic of China
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