武汉理工大学卜童乐研究员团队在 Nature Energy 期刊发表题为“Homogeneous coverage of the low-dimensional perovskite passivation layer for formamidinium–caesium perovskite solar modules”的研究论文，团队成员李静为论文第一作者，卜童乐研究员为论文通讯作者。
核心亮点：本文开发了一种通用策略，将甲脒（FA）阳离子加入大尺寸有机钝化剂中，以实现具有均匀形貌的相纯n值2D钙钛矿盖层。基于这种无抗溶剂沉积策略，在0.14 cm2的小尺寸器件、1.04 cm2的大尺寸器件和13.44 cm2的微型模块上，冠军有源面积效率分别达到25.61%、24.62%和23.60%，随着活性面积的增加，效率损失相对较小。
当将器件升级为模块时，基于纯相二维（2D）钙钛矿的均匀钝化层的形成对钙钛矿太阳能电池来说是一个挑战，为解决这一问题，武汉理工大学卜童乐研究员团队提出了一种有效的、可扩展的钝化策略，通过抑制在组成和维度方面不利的相分离，可以在3D钙钛矿表面均匀地形成相纯的2D钙钛矿覆盖层，揭示了生长在三维钙钛矿之上的二维钙钛矿的链长依赖和卤化物相关的相分离问题。证明了在长链（bbb10）烷基胺配体盐中使用溴甲脒处理钙钛矿层可以形成均匀的二维钙钛矿钝化层。对于无抗溶剂加工的小型（0.14 cm2）和大尺寸（1.04 cm2）器件以及小型模块（13.44 cm2），分别实现了25.61%，24.62%和23.60%的冠军有源面积效率。
此外，太阳能微型组件在MPPT下的T80寿命超过2000小时，表明了出色的稳定性。最显著的是，20 cm × 20 cm和30 cm × 30 cm的大尺寸psm在310 cm2和802 cm2的孔径面积上分别表现出18.90%和17.59%的冠军效率。这种同质化低维结构钝化策略对于加速psm的商业化具有相当大的潜力。
Fig. 1 | Compositional engineering of the 2D perovskite phase for scalable solar modules. a, Chemical structure of 2D ligands (RX) for passivation of perovskite films. RX represents the ammonium halides, in which R and X are organic ammoniums (depicted on the left-hand side) and halides (depicted on the right-hand side), respectively. BA, n-butylammonium; OA, n-octylammonium; DA, dodecylammonium; HDA, hexadecylammonium; PMA, phenmethylammonium; PEA, phenylethylammonium; NMA, 1-naphthylmethylammonium; PRMA, 1-pyrenemethylammonium. b, The schematic diagram of PSM with the structure of glass/FTO/SnO2/perovskite/passivator/spiro-OMeTAD/Au. c–e, PL (left) and local enlarged PL (right) spectra of perovskite films post-treated with different organic RX salts (c), DAX (d) and DAX/FABr (e). The grey box and coloured arrows in c highlight the appearance of n = 1 2D phase separation, which is observed in HDAI (pink arrow), DAI (blue arrow) and DACl (green arrow) samples. The vertical dashed lines indicate the PL peak position. f–h, Calculated formation enthalpies of R2PbI4 (n = 1) (f), DA2PbI4−xClx (n = 1) and DA2Pb(I2−0.5xCl0.5x)Br2 (n = 1) (g), and DA2FAPb2(I4−0.5xCl0.5x)Br3 (n = 2) and DA2FA2Pb3(I6−0.5xCl0.5x)Br4 (n = 3) (h). The y-axis break in g enables intuitive data comparison.
Fig. 2 | Growth kinetics and formation mechanism of the homogeneous 2D phase structure. a, In situ PL measurements of perovskite films with different organic salts post-treatment during spin coating. b, PL intensity evolution of the 3D perovskite phase derived from in situ PL measurements. The grey dashed lines and arrows with numbers highlight a turning point in the evolution of PL intensity. c, 2D GIWAXS data of perovskite films post-treated with different salts after annealing. d, 1D integrated intensity of 2D GIWAXS data along the out-of-plane scattering vectors, qz. e, The top-view and the cross-sectional SEM images of perovskite films post-treated with different organic slats. The yellow circles highlight distinct features of morphology. f, Schematic diagram of self-assembled different organic salts on the 3D perovskite surface producing different surface structures. V, vacancy.
Fig. 3 | Homogeneous surface morphology and defect passivation. a–d, AFM (a) and KPFM (c) images of different perovskite films (from left to right: pristine 3D, DABr- and DABr/FABr-treated perovskites) and the corresponding statistical distribution of height (b) and surface potential (d) derived from a and c, respectively. The curves on top of the data fit a Gaussian distribution. e,f, Timeresolved confocal PL mappings (e) and the trap densities (Nt) calculated from the dark current–voltage (I–V) curves of hole-only and electron-only devices (f) for the control,DABr-treated and DABr/FABr-treated perovskite films. g,h, In situ PL mapping of perovskite films post-treated with different organic salts (from left to right: pristine 3D, DABr- and DABr/FABr-treated perovskites) under continuous LED light source irradiation (g) and corresponding PL intensity evolution of the 3D peak (h).
Fig. 4 | Photovoltaic performance and stability characterization. a, J–V curves of small-sized devices with the post-treatment of different organic salts. b, J–V curve of the champion devices with the post-treatment of DABr/FABr. Inset: the corresponding photograph of a 1.04-cm2 large-sized device. c, EQE curve of the large-sized device with the post-treatment of DABr/FABr. d, J–V curve of the champion mini-module with the post-treatment of DABr/FABr. Inset: the photograph of a mini-module. e, Continuous MPP tracking for the encapsulated mini-module in ambient air. FF, fill factor; FS, forward scan; RS, reverse scan.
Fig. 5 | Scalable printed large-area modules. a, Schematic illustration for the scalable fabrication of large-sized PSMs with the corresponding laser processing (green cylinder) and the chemical bath deposition of large-scale SnO2 films (bottom inset). b, Photograph of a 30 cm × 30 cm PSM. c, J–V curve of the champion 20 cm × 20 cm sub-module with a series connection of 26 subcells. d, J–V curve of the champion 30 cm × 30 cm small module with a series connection of 42 subcells. PCEap, aperture-area efficiency; PCEac, active-area efficiency.
文章来源：DOI: 10.1038/s41560-024-01667-8
https://doi.org/10.1038/s41560-024-01667-8