【Nat.Mater.】华东理工朱为宏院士、吴永真、马巍、郑伟中联手华中科大陈炜|效率突破27.2%！全新自组装单分子层设计，双重提升反式钙钛矿电池光热稳定性#

文章标题：UV and thermally stable hole-selective contacts with enhanced assembly density for inverted perovskite solar cells

通讯作者：Wei Chen, Weizhong Zheng, Wei Ma, Wei-Hong Zhu & Yongzhen Wu

文章链接：https://doi.org/10.1038/s41563-026-02619-1

文章概要#

引言#

反式钙钛矿太阳能电池由于制备工艺简单、寄生吸收小及电子特性可调等优势，已成为下一代光伏技术的重要方向。其中，基于咔唑衍生物的自组装单分子层（SAM）因其卓越的空穴选择性收集能力，成为推动电池效率突破的关键核心组件。然而，咔唑基团在紫外线照射下极易发生降解，且传统的膦酸锚定基团在高温下面临热不稳定性，加之强极性溶剂对分子层吸附密度的破坏，严重制约了器件的长期稳定性与产业化进程。因此，开发兼具高光热耐受性与强界面吸附能力的全新SAM空穴传输材料是当前该领域亟待解决的瓶颈难题。

Fig. 1: Molecular design and UV stability.#

a, The configuration design idea of molecular-based HSC. b–e, Time-dependent UV–Vis absorption spectral evolution of MeO-2PACz (b), MP1 (c), MP2 (d) and MP3 (e) solutions under UV ageing (λ = 365 nm, 10 mW cm−2) at t = 0, 24 and 72 h. f,g, Normalized fluorescence (solid line) and delayed spectra (dotted line) of MeO-2PACz (f) and MP1 (g) dispersed in PMMA films. h,i, Time-resolved emission spectra of MeO-2PACz (h) and MP1 (i) dispersed in PMMA films at 25 °C. j,k, The absorbance of DPBF after the addition of MeO-2PACz (j) and MP1 (k) upon UV irradiation. l, Calculated C–N bond dissociation energies of MeO-2PACz and MP1. m, Calculated frontier molecular orbitals with energy level diagram of MeO-2PACz and MP1.#

主要实验及结论#

研究团队揭示了空穴材料的两条降解路径：非共轭链易发生紫外光解，而共轭结构易发生高温酐化热降解。为此设计的全新分子MP3巧妙融合了共轭与非共轭骨架，并引入吸电子氰基。这不仅成功抑制了上述光热降解，还通过降低pKa值，显著增强了其在衬底表面的锚定吸附密度与膜层均匀性，攻克了极性溶剂冲刷流失的难题。

Fig. 2: Molecular thermal stability.#

a–d, Evolution of 31P NMR spectra for MeO-2PACz (a), MP1 (b), MP2 (c) and MP3 (d) under thermal treatment at 150 °C (24 h, N2 atmosphere). e, TGA profiles of SAMs at 20 °C min−1 heating rate (N2 atmosphere). f, Proton conductivity of MeO-2PACz, MP1, MP2 and MP3 ethanol solutions measured at 25 °C before and after thermal treatment. Data are presented as the mean ± s.d. where n = 3 independent solutions measured for each proton conductivity. g, Calculated Gibbs free energy profiles for anhydride formation (MeO-2PACz and MP1) at 25 °C and 150 °C. h, Gibbs free energy of phosphonic anhydride formation as a function of p_K_a at 25 °C and 150 °C. Phenylphosphonic acid derivative (MP1), ethylphosphonic acid derivatives (MeO-2PACz and MP2) and cyanophosphonic acid derivative (MP3).#

Fig. 3: Characterizations on molecular assembly.#

a, A schematic illustration of SECCM for characterizing SAMs on ITO substrates. The two-electrode configuration comprised an ITO/SAM working electrode (WE) and an Ag wire QRCE, with 0.1 M tetrabutylammonium perchlorate (TBAP) dissolved in acetonitrile (ACN) as the electrolyte solution. b, Assembly densities mapping of different SAMs obtained from SECCM. c, Molecular adsorption densities on ITO quantified by SECCM. d, Calculated p_K_a of MeO-2PACz, MP1, MP2 and MP3. e, Molecular structures and p_K_a measured in ultrapure water. Data are presented as the mean ± s.d., where n = 3 independent solutions measured for each p_K_a value. f, Influence of the evolutionary design of the spacer group on the stability of phosphonic acid anions. The more stable the dissociated phosphonic acid anion, the easier it is for the phosphonic acid molecule to dissociate hydrogen ions.#

得益于更低的界面非辐射复合损失，MP3基反式钙钛矿太阳能电池获得了27.2%的冠军效率（认证效率27.1%）。该器件极具长效光热稳定性，在1000小时紫外光照后保持93.2%的效率，100℃热老化1000小时后保持91.1%，且在65℃最大功率点连续追踪2200小时后仍保留94.8%。

Fig. 4: Optoelectronic quality and stability of perovskite films.#

a, A schematic of the PL experiment and chemical structure of a general carbazole-based SAM, with different spacer groups. b,c, Steady-state PL spectra (b) and TRPL decays (c) of the perovskite films deposited on different SAMs. d, QFLS measurements. e, Pseudo J–V curves obtained from intensity-dependent QFLS. f, Time-dependent PL spectra of perovskite films on different SAMs under continuous UV-light exposure (365 nm, 10 mW cm−2) from the glass side at 65 °C.#

Fig. 5: Device performance.#

a, A schematic diagram of the PSC structure. b–e, Statistics parameters of _V_OC (b), _J_SC (c), FF (d) and PCE (e) for MeO-2PACz-, MP1-, MP2- and MP3-based devices with an area of 0.08 cm2 (12 devices for each type). The box plot indicates the minimum (bottom line), maximum (top line), median (centre line), 75th percentile (top edge of the box) and 25th percentile (bottom edge of the box). f, Representative J–V curves for MP1-, MP2- and MP3-based champion device with an area of 0.08 cm2. Steady-state power output of MP3-based device. g, EQE and integrated _J_SC curves of MP3-based champion device. h, J–V curves of MP3-based champion device with an area of 1.00 cm2. RS, reverse scan; FS, forward scan. i, UV stability measurements of encapsulated PSCs under 365 nm UV light (10 mW cm−2) in air from the glass side. Data are presented as the mean ± s.d. Sample size n is defined as the number of devices tested: n = 4 for all cases. j, Thermal stability of unencapsulated devices under heating at 100 °C in N2. Data are presented as the mean ± s.d. Sample size n is defined as the number of devices tested: n = 4 for all cases. k, Continuous MPP tracking of encapsulated devices under continuous 1-sun illumination in ambient environment.#

总结及展望#

这项研究为钙钛矿太阳能电池及其他薄膜光电集成器件的界面功能分子设计提供了全面的理论指导与实践范式。通过精准的分子空间工程与极性电子基团调控，不仅成功打破了界面材料在高效光电转换与严酷光热环境耐受性之间的传统博弈，更为反式钙钛矿光伏技术的商业化量产与产业化落地奠定了稳固的基础。未来，这种强化界面吸附与稳定性的分子改性策略有望广泛应用于大面积组件及多场景光伏应用中。