二价阳离子掺杂优化铜锌锡硫(硒)薄膜太阳能电池性能的研究进展

赵鑫; 杨艳春; 崔国楠; 刘艳青; 任俊婷; 田晓; 朱成军

doi:10.13801/j.cnki.fhclxb.20230515.001

二价阳离子掺杂优化铜锌锡硫(硒)薄膜太阳能电池性能的研究进展

doi: 10.13801/j.cnki.fhclxb.20230515.001

赵鑫¹,
杨艳春^{1, 2, ,},
崔国楠¹,
刘艳青¹,
任俊婷¹,
田晓¹,
朱成军^2, ,

1.
内蒙古师范大学　物理与电子信息学院，呼和浩特 010022
2.
内蒙古大学　物理科学与技术学院，呼和浩特 010021

基金项目: 国家自然科学基金(62164010；62064010)；中央引导地方科技发展资金(2020ZY0009)；中国博士后科学基金(2019M653806XB)；内蒙古师范大学校级研究生科研创新基金发展资金(CXJJS22105)

详细信息

通讯作者:
杨艳春，博士，副教授，硕士生导师，研究方向为光伏材料制备及性能研究工作，包括铜锌锡硫硒、有机-无机钙钛矿材料的光伏性能、发光性能的研究　E-mail: 20170020@imnu.edu.cn；

朱成军，博士，教授，博士生导师，研究方向为新能源材料与器件：薄膜太阳能电池材料与器件、低温固体氧化物燃料电池材料与器件E-mail: ndcjzhu@126.com

中图分类号: TM914.4；TB33
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出版历程
- 收稿日期: 2023-03-07
- 修回日期: 2023-04-24
- 录用日期: 2023-05-04
- 网络出版日期: 2023-05-15
- 刊出日期: 2023-11-01

Research progress on optimizing performance of Cu₂ZnSnS₄(Cu₂ZnSn(S,Se)₄) thin-film solar cells by bivalent cations doping

1.
School of Physics and Electronic Information, Inner Mongolia Normal University, Hohhot 010022, China
2.
School of Physics Science and Technology, Inner Mongolia University, Hohhot 010021, China

Funds: Natural Science Foundation of China (62164010; 62064010); Central Government Guides Local Funds for Science and Technology Development (2020ZY0009); China Postdoctoral Science Foundation (2019M653806XB); Inner Mongolia Normal University Graduate Research and Innovation Fund Development Fund (CXJJS22105)

摘要

摘要: 阳离子掺杂措施被认为是调节优化铜锌锡硫硒薄膜(Cu₂ZnSn(S, Se)₄，CZTS(Se))太阳能电池有效措施之一，其中，二价阳离子掺杂措施是研究最多、应用最广的。本文从阳离子取代和阳离子额外添加两个方面详细介绍了二价阳离子掺杂措施在优化CZTS(Se)薄膜太阳能电池性能方面的研究进展，二价阳离子取代措施，如Cd²⁺取代Zn²⁺等，主要是可以有效降低CZTS(Se)薄膜太阳能电池吸收层的缺陷密度，提高结晶质量，解决吸收层和缓冲层之间界面能带偏移值较大的问题，从而减少电池器件的开路电压亏损，提高器件效率；二价阳离子的额外添加，如Co、Mn的额外添加，主要是优化薄膜的结晶性、帮助载流子的输运，提高吸收层薄膜的电学性能；最后，也总结两类阳离子掺杂措施的优缺点及应用前景。
- 铜锌锡硫 /
- 铜锌锡硫硒 /
- 薄膜太阳能电池 /
- 二价阳离子的取代 /
- 二价阳离子的额外添加
Abstract: Cation doping measures are considered as one of the effective measures to optimize the performance of Cu₂ZnSn(S,Se)₄ (CZTS(Se)) thin film solar cells, and divalent cation doping measures are the most studied and widely applied in all cation doping measures. Here, the research progress of divalent cation measures in optimizing the performance of CZTS(Se) thin film solar cells is introduced from two aspects: Cations substitution and extra cations addition. Divalent cations substitution measures, such as, substitution of Zn²⁺ with Cd²⁺, mainly reduce the defect density of the absorber layer of CZTS(Se) thin film solar cells, improve the crystalline quality, and solve the problem of large interface energy band offset between the absorber layer and buffer layer, thus reducing the open voltage circuit loss of the device and improving its efficiency. The extra addition of divalent cations, such as, the extra addition of Co²⁺/Mn²⁺, can optimize the crystallinity of the film, help the carrier transport, and improve the electrical properties of the absorber layer. Finally, their advantages, disadvantages, and the application prospects are also summarized.
- Cu₂ZnSnS₄ /
- Cu₂ZnSn(S,Se)₄ /
- thin film solar cell /
- divalent cations substitution /
- extra addition of divalent cations

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图 1 Cu₂ZnSnS₄(CZTS)和Cu₂Zn_1-xMg_xSnS₄(CZMTS)吸收层XRD图谱 (a) 和Raman图谱 (b)(插图为(112)衍射峰放大图)^[49]

Figure 1. XRD patterns (a) and Raman scattering spectra (b) of Cu₂ZnSnS₄ (CZTS) and Cu₂Zn_1-xMg_xSnS₄ (CZMTS) absorber (The inset is the enlarged view of the (112) diffraction peak)^[49]

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图 2 Cu₂ZnSnS₄和Cu₂Zn_1-xMg_xSnS₄吸收层横截面电场发射扫描电子显微镜(FESEM)图像^[49]

Figure 2. Field emission scanning electron microscope (FESEM) cross-sectional images of the Cu₂ZnSnS₄ and Cu₂Zn_1-xMg_xSnS₄ absorber^[49]

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图 3 Cu₂Zn_1-xBa_xSn(S,Se)₄薄膜表面SEM图像^[52]

Figure 3. SEM images of the Cu₂Zn_1-_xBa_xSn(S,Se)₄ thin films surface^[52]

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图 4 Cu₂BaSnSe₄中本征缺陷在化学势点处的形成焓(ΔH)与费米能级(E_F)的关系：(a) Cu-poor和Se-intermediate; (b) Cu-rich和Se-poor; (c) Cu-poor和Se-rich^[53]

Figure 4. Calculated formation enthalpies (ΔH) of intrinsic defects in Cu₂BaSnSe₄ as a function of Fermi level (E_F) at the chemical potential points: (a) Cu-poor and Se-intermediate; (b) Cu-rich and Se-poor; (c) Cu-poor and Se-rich^[53]

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图 5 器件参数与微量Ca掺杂Cu₂Ca_xZn_1-xSn(S,Se)₄(Ca/(Ca+Zn)%)的关系^[55]

PCE—Power conversion efficiency; V_OC—Open circuit voltage; J_SC—Short-circuit current density; FF—Fill factor

Figure 5. Relationship of the detail device parameters with trace Ca-doped Cu₂Ca_xZn_1-xSn(S,Se)₄ (Ca/(Ca+Zn)%) devices^[55]

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图 6 在不同μ_Cu下Cu₂ZnSnS₄在(μ_Zn, μ_Sn)面的稳定化学势区域(黑色区域)和在(μ_Cu,μ_Zn, μ_Sn)化学势^[29]

μ—Chemical potential

Figure 6. Calculated stable chemical potential region (black area) of Cu₂ZnSnS₄ in (μ_Zn, μ_Sn) planes with different μ_Cu in the (μ_Cu, μ_Zn, μ_Sn) chemical potential spaces^[29]

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图 7 Cu₂Zn_1-xNi_xSnS₄中带隙、价带偏移(VBO)、导带偏移(CBO)随Ni浓度变化^[63]

Figure 7. Plot of variation of band gaps, valence band offset (VBO) and conduction band offset (CBO) versus Ni composition in Cu₂Zn_1-xNi_xSnS₄^[63]

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图 8 Cu₂Ni_xZn_1-xSn(S,Se)₄(0≤x≤0.1)薄膜SEM图像^[61]

Figure 8. SEM images of the Cu₂Ni_xZn_1-xSn(S,Se)₄ (0≤x≤0.1) films^[61]

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图 9 CZTS和Cu₂(Zn_0.96Cr_0.04)SnS₄薄膜能带图及价带(E_v)、中间带(E_i)、费米能级(E_F)和导带(E_c)相对于真空能级(E_vac)的位置^[65]

Figure 9. Calculated band diagram of CZTS and Cu₂(Zn_0.96Cr_0.04)SnS₄ films and position of valence band (E_v), intermediate band states (E_i), fermi level (E_F) and conduction band (E_c) with respect to vacuum level (E_vac)^[65]

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图 10 以Cu₂Zn_1-xCr_xSnS₄为吸收层的电池性能参数与x的关系^[65]

Figure 10. Output parameters of the cells with Cu₂Zn_1-xCr_xSnS₄ absorber layers as the functions of x^[65]

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图 11 Cu₂Mn_xZn_1-xSn(S,Se)₄薄膜表面和截面SEM图像^[71]

Figure 11. Surface and cross-sectional SEM images of Cu₂Mn_xZn_1-_xSn(S,Se)₄ thin films^[71]

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图 12 (a)不同Co掺杂比(0mol%、1mol%、3mol%、5mol%) CZTS(Se)的XRD图谱； (b) (112)衍射峰的放大图^[82]

Figure 12. (a) XRD patterns of CZTS(Se) samples with different trace Co incorporation ratio (0mol%, 1mol%, 3mol%, 5 mol%); (b) Enlarged view of (112) peaks^[82]

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图 13 不同Mn掺杂比CZTS(Se)薄膜的AFM形貌和c-AFM表面电流图像：((a), (b)) 0mol%；((c), (d)) 1mol%；((e), (f)) 3mol%；((g), (h)) 5mol%；((i), (j)) 7mol%^[23]

Figure 13. AFM topography and c-AFM surface current images of CZTS(Se) thin films with the different Mn-doping ratios: ((a), (b)) 0mol%; ((c), (d)) 1mol%; ((e), (f)) 3mol%; ((g), (h)) 5mol%; ((i), (j)) 7mol%^[23]

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表 1 CZTS和CZCTS 样品的电性能^[58]

Table 1. Electrical characteristics of the CZTS and CZCTS samples^[58]

Absorber	Optical E_g/eV	PL peak/eV	Δ(E_g–PL peak)/mV	E_Urbach/meV
CZTS	1.54	1.37	~170	65
CZCTS	1.38	1.31	~70	45
Notes: E_g—Band gap; PL—Photoluminescence; Δ(E_g–PL peak)—Difference between the optical band gap and PL peak, correlated with the extent of band tailing; E_Urbach—Urbach tail energy, is used to account for sub-band gap photon absorption and the characterized band tailing; CZCTS—Cu₂Zn_0.6Cd_0.4SnS₄.

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表 2 不同二价阳离子掺杂所取得的最高铜锌锡硫硒(CZTS(Se))薄膜太阳能电池参数

Table 2. Paramaters of the hightest Cu₂ZnSn(S,Se)₄ (CZTS(Se)) thin-film solar cell by different divalent cation doping

Battery device name	V_OC/mV	J_SC/(mA·cm⁻²)	FF/%	η/%	Ref.
Cu₂Mg_0.0357Zn_0.9643Sn(S,Se)₄	400.15	33.45	57.93	7.76	[50]
Cu₂Ba_0.01Zn_0.9Sn(S,Se)₄	424.00	32.30	66.80	9.14	[52]
Cu₂Ca_0.02Zn_0.8Sn(S,Se)₄	417.00	35.84	58.00	8.73	[54]
Cu₂Zn_0.6Cd_0.4SnS₄	640.00	27.80	71.00	12.60	[18]
Cu₂Ni_0.05Zn_0.95Sn(S,Se)₄	351.00	33.62	45.05	5.32	[60]
Cu₂Zn_0.96Cr_0.04SnS₄	568.00	14.00	49.80	3.96	[64]
Cu₂Mn_0.05Zn_0.95Sn(S,Se)₄	418.00	33.70	63.30	8.90	[70]
Cu₂Co_0.03Zn_0.97Sn(S,Se)₄	340.00	26.85	43.30	3.95	[71]
Notes: V_OC—Open circuit voltage; J_SC—Short-circuit current density; FF—Fill factor; η—Light-to-electricity conversion efficiency.

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