近日，昆明理工大學材料科學與工程學院陳江照教授團隊在國際材料與能源權威期刊ACS Energy Letters上以“Synergistically stabilizing hole transport layer and dual interface enables high-performance perovskite solar cells”為題發表最新研究成果，該研究工作得到國家自然科學基金面上、兵團重點領域科技攻關計劃等項目的資助。
高效率的n-i-p型鈣鈦礦太陽能電池（PSCs）通常依賴于摻雜Li-TFSI和tBP的有機空穴傳輸層（HTL）。然而，Li+和鹵素離子的遷移和擴散以及tBP的揮發嚴重制約PSCs的長期運行穩定性。鑒于此，陳江照教授團隊采用l -谷氨酸二芐基酯- 4甲苯磺酸鹽（GADET）同時調控HTL和埋底界面，通過固定Li+、tBP和鹵素離子及鈍化雙界面缺陷，穩定HTL，減少界面能損失。GADET通過苯磺酸陰離子與Li+的離子鍵相互作用抑制了Li+離子的擴散，而-NH3+與tBP形成氫鍵可以抑制tBP的揮發。此外，通過鈍化未配位Pb2+和鹵素空位缺陷，能夠有效抑制鹵素離子遷移和界面陷阱誘導的非輻射復合。協同優化的器件實現了25.06%的冠軍功率轉換效率（認證PCE為24.08%）。目標器件分別在35-45%相對濕度條件下老化3000 h、65℃熱老化2000 h、一個太陽模擬光連續照射1200 h后分別保持了原始效率的95.02%、91.21%和80.23%。
Fig. 1 Promoting doping and its mechanism investigation via introducing GADET. (a) ESR spectra of the Spiro-OMeTAD films without and with GADET doping. (b) 7Li NMR of the LiTFSI solution without and with GADET. (c) Doping efficiency enhancement and HTL stabilization mechanisms upon incorporating GADET. (d) UV-vis spectra of the Spiro-OMeTAD solutions with gradual addition of GADET (without LiTFSI and tBP). The solutions were prepared in the nitrogen glove box. The measurement was conducted in ambient condition. (e) J-V curves of the champion devices based on the Spiro-OMeTAD solutions containing different concentrations of GADET (without LiTFSI and tBP).
Fig. 2 Stabilizing HTL and Ag electrode via suppressing Li+ and halide ions migration and diffusion by GADET modification. TOF-SIMS depth distribution of perovskite/HTL films without (a) and with (b) GADET which were aged under light and heat at 60 ℃ for 240 h in a nitrogen filled glovebox. Cross-sectional SEM images of the HTLs without (c) and with (d) GADET after aging under light and heat at 60 ℃ for 240 h in a nitrogen filled glovebox, (e) Schematic diagram of halogen ion migration and AgI formation in the devices based on pristine HTL.
Fig. 3 Modulation mechanisms of buried interface via GADET. (a) XPS spectra of Sn 3d from the SnO2 films with and without GADET treatment. (b) FTIR spectra of the pristine and treated SnO2 films with GADET. XPS spectra of (c) Pb 4f and (d) O 1s from the perovskite films with and without GADET. (e) Schematically illustrated diagram of the buried interface defect passivation by GADET.
Fig. 4 Carrier dynamics study. (a) SSPL and (b) TRPL spectra of the perovskite films deposited on non-conductive glass without and with bottom surface passivation, top surface passivation or synergistic passivation via GADET. (c) Defect density for the perovskite films without and with bottom surface passivation, top surface passivation or dual surface passivation by GADET. (d) VOC versus light intensity for the devices with or without modification. (e) TPV curves for the control and modified PSCs. (f) Energy band diagram of all device components.
Fig. 5 J-V curves of the champion devices (a) without and (b) with synergistic modification based on perovskite composition Rb0.02(FA0.95Cs0.05)0.98PbI2.91Br0.03Cl0.06 (0.1 cm2).(c) Moisture stability of the unencapsulated devices aged under a relative humidity of 35-45% at room temperature in the dark. (d) Thermal stability of the unencapsulated devices kept at 65 ℃ in a nitrogen-filled glovebox in the dark. (e) Light stability of the unencapsulated devices under an illumination of 100 mW/cm2 provided by white light LED at room temperature in the nitrogen-filled glovebox (5 devices).
文章鏈接：
Dongmei He#, Danqing Ma#, Ru Li#, Baibai Liu, Qian Zhou, Hua Yang, Shirong Lu, Zhengfu Zhang, Caiju Li, Xiong Li, Liming Ding, Jing Feng, Jianhong Yi, Jiangzhao Chen*. Synergistically stabilizing hole transport layer and dual interface enables high-performance perovskite solar cells. ACS Energy Letters 2024, 9, 2615-2625.
https://pubs.acs.org/doi/10.1021/acsenergylett.4c00816
