Eliminating multi-layer crystallization of Cu2ZnSn(S,Se)4 absorber by controlling back interface reaction

Broadening the processing window is of high importance for developing efficient Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. Herein, a high efficiency (active‐area: 13.5%) of CZTSSe solar cells achieved from thioglycolic acid (TGA)‐ammonia based water solution method is first reported. The cell performance exhibits the high tolerance to the element composition variations of the CZTSSe film. Film crystallization and chemical mechanism studies reveal that this high composition‐tolerance mainly benefits from an existence of a conductive carbon framework layer with high element accommodating ability and a phase‐segregation growth behavior of CZTSSe grains driven by thermodynamics properties of the heterogeneous film system. It is shown that Sn–TGA coordination capable to induce large metal–organic molecule clusters plays a critical role in forming the mesoscopic carbon layer. These results and related material mechanism provide new routes to regulate crystal growth of the CZTSSe film for further improving cell performance.

show abstract

Section: Resultsmentioning

confidence: 99%

Efficient and Composition‐Tolerant Kesterite Cu₂ZnSn(S, Se)₄ Solar Cells Derived From an In Situ Formed Multifunctional Carbon Framework

Guo

Zhou

et al. 2021

Advanced Energy Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…That is, the cross‐sectional structure of the absorber layer is changed from the double layer (Figure 2e) to a single layer (Figure 2f), possibly because the ALD‐Al 2 O 3 introduces nucleation sites to promote growth. [ 43 ] To further make clear the change of samples with and without Al 2 O 3 , we measured three different samples prepared at different preparing batches with the same experimental condition for each type of sample, i.e., with and without Al 2 O 3 , as shown in Figure S4, Supporting Information. A bilayer structure is observed for all three samples for CZTSSe without Al 2 O 3 (Figure S4a–c, Supporting Information) and a single‐layered structure is observed for all three samples for CZTSSe with Al 2 O 3 (Figure S4d–f, Supporting Information).…”

Section: Resultsmentioning

confidence: 99%

Defect Control for High‐Efficiency Cu₂ZnSn(S,Se)₄ Solar Cells by Atomic Layer Deposition of Al₂O₃ on Precursor Film

et al. 2021

View full text Add to dashboard Cite

Cu2ZnSn(S,Se)4 are emerging as promising photovoltaic materials due to their outstanding photoelectrical performances, benign grain boundaries, and Earth‐abundant constituent elements. However, there are largely distributed cation‐disordering defects and defect clusters, which lead to an increase in recombination and a large open‐circuit voltage deficit and thus deteriorate device performance. Herein, defect control for a high‐efficiency Cu2ZnSn(S,Se)4 solar cell by atomic layer deposition of aluminum oxide (ALD‐Al2O3) on the precursor film is reporter. CuZn defects and Sn‐related deep defects are largely suppressed because of the decrease in Sn2+ and the increase in Sn4+ in the film by ALD‐Al2O3 on the precursor are found, and the crystallinity of absorber layer is improved from a double‐layer structure to a completely single‐layer structure. Furthermore, the carrier lifetime and recombination in the bulk and interface are significantly improved for devices with ultrathin Al2O3. Using this approach, the conversion efficiency increases from 8.8% to 11.0% and the open‐circuit voltage deficit decreases from 0.621 to 0.577 V. Herein, a deep understanding of the relationship between Al2O3 incorporation and high‐efficiency Cu2ZnSn(S,Se)4 devices and a new direction for controlling defects to further improve the performance of kesterite solar cells are provided.

show abstract

“…值得注意的是, 对于不同的溶剂体系, 其结晶过程也有所不同. CZTSSe 薄膜有单层结晶、双层结晶和三层结晶等生长方式 [33][34][90][91]94] . 其中, Ag ＋对于双层结晶晶粒的影响会有所不同, 例如, Rakesh 等 [97] [77] : ( [90,94] , 钠钙玻璃(SLG)中扩散到吸收层中的 Na 含量也会减少.…”

Section: LIunclassified

“…该小晶粒层导电, 不会形成高阻绝缘层, 对于消除背界面孔洞有积极作用 [33] . 对于金属-硫脲体系, 与金属配位的是硫脲, 而硫脲在如二甲亚砜、乙二醇甲醚、水等溶剂中大多容易分解, 通过调节硒化参数和增加背界面阻挡层完全消除小晶粒层 [27,34] , 该类体系可以实现贯穿大晶粒 , 有利于 CZTSSe 性能进一步提升.…”

unclassified

Research Progress of Metal(I) Substitution in Cu₂ZnSn(S,Se)₄ Thin Film Solar Cells

Zhou¹,

Xu²,

Duan³

et al. 2021

Acta Chimica Sinica

Self Cite

View full text Add to dashboard Cite

Cu2ZnSn(S,Se)4 solar cell (CZTSSe), as a new type of inorganic thin-film solar cells, has been widely studied in recent years due to the advantages of earth-abundant and environmental-friendly composition elements, high light absorption coefficient and adjustable band gap. CZTSSe solar cell is thus a highly competitive photovoltaic device with potential applications in flexibility, building integrated photovoltaics (BIPV) and so on. So far, 12.6% certified efficiency has been achieved for this kind of solar cells. Open-circuit voltage (VOC) deficit is always the key factor to unsatisfied efficiency of CZTSSe solar cells, and band tailing, mismatch of energy band structure and deep level defects are the main causes to VOC deficit. Typically, Cu-Zn disorder-induced defects widely exist in the bulk absorber, due to similar radius of Cu and Zn elements could lead to relatively low formation energy of CuZn and ZnCu anti-site defects. Metal(I) substitution is an effective way to solve Cu-Zn disorder, which can well reduce VOC deficit via lowering band tailing and improving the device structure, leading to better cell performance. However, very few review papers have focused on the metal(I) substitution work. In this review, we will summarize the research progress of metal(I) substitution in Cu2ZnSn(S,Se)4 thin film solar cells. Part I introduces the structure and problems of CZTSSe solar cells. Part II shows the origin of metal(I) substitution and theoretical research on substituted materials. Part III focuses on synthetic methods about metal(I) partial substitution devices and influence on crystal growth, band tailing, interface defects and band structure. Part IV briefly introduces metal(I) total substitution devices. Part V anticipates the prospects and bottleneck of metal(I) substitution devices, and give some possible solutions to these current

show abstract

Eliminating multi-layer crystallization of Cu2ZnSn(S,Se)4 absorber by controlling back interface reaction

Cited by 67 publications

References 37 publications

Efficient and Composition‐Tolerant Kesterite Cu₂ZnSn(S, Se)₄ Solar Cells Derived From an In Situ Formed Multifunctional Carbon Framework

Efficient and Composition‐Tolerant Kesterite Cu₂ZnSn(S, Se)₄ Solar Cells Derived From an In Situ Formed Multifunctional Carbon Framework

Defect Control for High‐Efficiency Cu₂ZnSn(S,Se)₄ Solar Cells by Atomic Layer Deposition of Al₂O₃ on Precursor Film

Research Progress of Metal(I) Substitution in Cu₂ZnSn(S,Se)₄ Thin Film Solar Cells

Contact Info

Product

Resources

About

Eliminating multi-layer crystallization of Cu2ZnSn(S,Se)4 absorber by controlling back interface reaction

Cited by 67 publications

References 37 publications

Efficient and Composition‐Tolerant Kesterite Cu2ZnSn(S, Se)4 Solar Cells Derived From an In Situ Formed Multifunctional Carbon Framework

Efficient and Composition‐Tolerant Kesterite Cu2ZnSn(S, Se)4 Solar Cells Derived From an In Situ Formed Multifunctional Carbon Framework

Defect Control for High‐Efficiency Cu2ZnSn(S,Se)4 Solar Cells by Atomic Layer Deposition of Al2O3 on Precursor Film

Research Progress of Metal(I) Substitution in Cu2ZnSn(S,Se)4 Thin Film Solar Cells

Contact Info

Product

Resources

About

Efficient and Composition‐Tolerant Kesterite Cu₂ZnSn(S, Se)₄ Solar Cells Derived From an In Situ Formed Multifunctional Carbon Framework

Efficient and Composition‐Tolerant Kesterite Cu₂ZnSn(S, Se)₄ Solar Cells Derived From an In Situ Formed Multifunctional Carbon Framework

Defect Control for High‐Efficiency Cu₂ZnSn(S,Se)₄ Solar Cells by Atomic Layer Deposition of Al₂O₃ on Precursor Film

Research Progress of Metal(I) Substitution in Cu₂ZnSn(S,Se)₄ Thin Film Solar Cells