27.6% Perovskite/c‐Si Tandem Solar Cells Using Industrial Fabricated TOPCon Device

Abstract

The tandem cell structure is the most promising solution for the next generation photovoltaic technology to overcome the single‐junction Shockley–Queisser limit. The fabrication of a perovskite/c‐Si monolithic tandem device has not yet been demonstrated on a c‐Si bottom cell produced from an industrial production line. Here, a c‐Si cell with a tunneling oxide passivating contact (TOPCon) structure produced on a production line as the bottom cell of a tandem device, and a top cell featuring solution‐processed perovskite films to form the tandem device are used. The c‐Si cell features a rough damage etched, but untextured front surface from the wafering processes. To combat the challenge of rough surfaces, several strategies to avoid shunt paths across carrier transport layers, absorber layers, and their interfaces are implemented. Moreover, the origin of reflection loss on this planar structure is investigated and the reflection loss is managed to below 4 mA cm−2. In addition, the source of the voltage loss from the TOPCon bottom cell is identified and the device structure is redesigned to be suitable for tandem applications while still using mass production feasible fabrication methods. Overall, 27.6% efficiency is achieved for a monolithic perovskite/c‐Si tandem device, with significant potential for future improvements.

Atomic Layer Deposited ZnO–SnO2 Electron Transport Bilayer for Wide‐Bandgap Perovskite Solar Cells

“…All the samples exhibit almost the same morphology and luminance contrast on the irregular surfaces, which indicates the high uniform surface coverage as well as the good conductivity. [ 16,51 ] The surface roughness was further verified by the conformal surface coverage, as proven by the atomic force microscopy (AFM) images (Figure 4e–h). The root mean square (RMS) of bare and ZnO, SnO 2 , ZnO–SnO 2 capped FTO is 25, 27.2, 26.3, and 24.7 nm, respectively, indicating the accurate self‐limited growing process and a uniform pinhole‐free film deposited by ALD.…”

Research progress of perovskite/crystalline silicon tandem solar cells with efficiency of over 30%

“…Perovskite/SHJ TSC structures with (a) n-i-p and (b) p-i-n. Absorption and reflection spectra of optimized TSCs for the (c) regular architecture and (d) inverted architecture [39] . [26] 的晶 硅衬底上采用溶液法制备 PSCs，然后通过光学工程 [40,41] 解决平面界面光反射损 失； 其二， 保留绒面结构和陷光效果， 开发保型沉积钙钛矿层电池的新方法 [42][43][44][45] 。 3.1 平面结构 在平面晶硅电池上进行光学工程能够有效降低界面光损失。Wu 等人 [26] 报道 了钙钛矿/钝化发射极背接触(PERC)TSC 结构(图 9a) 。基于平面的 PERC 电 池前表面结构，通过保留受光面的 SiN x 减反射膜最大程度上降低了平面界面处 的光反射。然后，通过选择性地去除局部 ARC 膜，并在开口处热蒸发 Cr/Pd/Ag 金属触点实现子电池间的电荷传输。该设计提高了底电池的光学和钝化性能，获 得了 PCE 为 22.8%的 TSC(图 9b) 。理论上，通过进一步优化 Cr/Pd/Ag 分布和 ITO 电导率，电性能将会继续提升。Mazzarella 等人 [40] 将 HJT 底电池中的 n-a-Si H 替换为 n 型 nc-SiO x H(图 9c) ，降低了对可见光的吸收。然后根据四分之一波 长减反射原理优化 nc-SiO x H 层的厚度(110 nm)和折射率(2.6@800 nm) (图 9d) 。基于 Cs 0.05 (FA 0.83 MA 0.17 ) 0.95 Pb(I 1-x Br x ) 3 钙钛矿/HJT TSC，获得了经认证的 25.43%的稳定 PCE(图 9e) 。这项工作提供了一种改善平面互联界面上光学损失 的有效方法。Wu 等人 [41] 制备了钙钛矿/隧穿氧化物钝化接触(TOPCon)TSC。 考虑到 Poly-Si/ITO/NiO x 折射率失配的问题，通过降低 ITO 厚度降低界面反射， 叠加 IZO 透明电极厚度和受光面栅线间距优化， 将反射率控制在 4 mA cm -2 以下， 最终叠层器件效率达到 27.68%，其中 Jsc 为 19.68 mA cm -2 。 图 9 钙钛矿/晶硅 TSC 的(a)结构示意图和(b)J-V 曲线 [26] ；( c)钙钛矿/HJTTSC 结构示 意图； (d)材料的折射率(n)对比；1.1 cm 2 的最优电池的(e)J-V 曲线和(f)EQE 曲线 [40] Fig. 9.…”

Conductive Passivator for Efficient Monolithic Perovskite/Silicon Tandem Solar Cell on Commercially Textured Silicon

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cells (TSCs) has been boosted to 31.3% by École Polytechnique Fédérale de Lausanne (EPFL) recently. [3] There are several studies of perovskite/silicon TSCs concerning solution-based perovskite top cells processed on front polished [4][5][6][7][8][9][10] or specifically sized pyramidical [11][12][13][14] silicon substrates that have demonstrated considerable progress. Directly employing commercially textured silicon from the well-established standard industrial processes without additional polish process or pyramid size design allows to preserve the best performance of bottom silicon cells and maximizes light trapping at the least cost, thus, is of great significance.

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