-
Abstract: Colloidal quantum dot (CQD) lasers show promising applications in flexible optoelectronic devices, due to their tunable emission wavelength, narrow spectrum bandwidth and high power intensity. However, fabricating a flexible CQD laser is challenging because of the difficulties in fabricating optical cavities on flexible substrates using traditional microfabrication technologies. Herein, we propose a one-step self-assembly approach to fabricate flexible CQD supraparticle lasers. The whole assembly approach is processed in a liquid environment without surfactants, and the formed spherical CQD supraparticles are featured with smooth surfaces, serving as high-quality-factor whispering-gallery mode cavities to support laser oscillation. A low lasing threshold of 54 µJ/cm2 is observed while exciting a CQD supraparticle with pulsed femtosecond lasers. The calculated cavity quality factor of 963 for CQD supraparticle lasers is twofold larger than that of CQD lasers assembled with surfactants. Moreover, the CQD supraparticles can serve as free-standing lasers, which allows them to be deposited on flexible substrates such as paper and cloth. Furthermore, our CQD lasers show high stability, after being continuously photoexcited above the threshold for 400 min, their lasing intensity remains at 85.7% of the initial value. As bright, free-standing and long-term stable light sources, the assembled CQD lasers proposed in this work show potential applications in wearable devices and medical diagnosis.
-
Key words:
- Colloidal quantum dot /
- Supraparticle /
- Laser /
- Flexible device
-
Figure 1. Characterization of CdSe/CdS CQDs.
(a) TEM image of CQDs. The inset figure shows the size distribution statistics, showing a mean value of ~10 nm. (b) XRD pattern of a drop-casted CQD film on a nondiffraction silicon substrate. The characteristic diffraction peaks between 20° and 35° confirm the wurtzite crystalline structure [29]. (c) Normalized absorbance and photoluminescence spectra of the CQD solutions. There is a 5 nm Stokes shift between the first absorption and the emission peaks. (d) PL decay of the CQD films under low (26 μJ/cm2 ) and high (382 μJ/cm2) photoexcitation power densities. The one collected under low photoexcitation intensity shows a single exponential decay with a fitted lifetime of ~16 ns, and the other one collected under high photoexcitation intensity reveals a biexciton lifetime of ~1 ns.
Figure 2. Assembly process from CQDs to CQD SPs and the morphological characterizations of CQD SP.
(a) A schematic diagram of the assembly process. (b, c) SEM images of a CQD SP with different surface magnification. (d,e) SEM images of a CQD SP before (d) and after (e) being cut by a focused ion beam. We can infer that SPs are solid spheres packed with CQDs.
Figure 3. Lasing threshold measurements.
(a) Emission spectra of a CQD SP as a function of the photoexcitation energy density from 17 μJ/cm2 to 84 μJ/cm2. The insets are optical micrographs of the CQD SP under photoexcitation below and above the lasing threshold, respectively. Below the threshold, the emission spectrum is dominated by spontaneous emission. Optical modes circulating around the CQD SP can be observed as we increase the input power to a certain value, indicating the occurrence of laser oscillation (Mov. S2 in SM records the optical micrographs of the CQD SP dominated from spontaneous emission to lasing). (b) Dependence of the peak emission intensity and FWHM on the photoexcitation energy density. The lasing threshold of the CQD SP is 54 µJ/cm2, and the cavity quality factor is 963.
Figure 4. Free-standing CQD lasers on flexible substrates.
(a) Schematic diagram of the fabrication of a flexible laser device. A flexible laser can be readily fabricated by drop-casting the CQD SP solution on a flexible substrate. (b) Laser spectrum of a CQD SP dispersed in DMF. The inset is the optical micrograph of the lasing CQD SP and SM Mov. S3 records the optical micrographs of the lasing CQD SP dispersed in DMF. (c, d) Laser spectra of a CQD SP on a bent frosted paper (c) or on curved cloth (d). The insets are the corresponding far-field photographs.
-
[1] D. V. Talapin, A. L. Rogach, A. Kornowski, M. Haase, and H. Weller, Nano Lett. 1, 207 (2001). doi: 10.1021/nl0155126 [2] D. A. Hanifi, N. D. Bronstein, B. A. Koscher, Z. Nett, J. K. Swabeck, K. Takano, A. M. Schwartzberg, L. Maserati, K. Vandewal, Y. van de Burgt, A. Salleo, and A. P. Alivisatos, Science 363, 1199 (2019). doi: 10.1126/science.aat3803 [3] A. P. Alivisatos, Science 271, 933 (1996). doi: 10.1126/science.271.5251.933 [4] C. B. Murray, D. J. Norris, and M. G. Bawendi, J. Am. Chem. Soc. 115, 8706 (1993). doi: 10.1021/ja00072a025 [5] H. Zhang, Y. Yang, and X. Liu, Chin. J. Chem. Phys. 31, 197 (2018). doi: 10.1063/1674-0068/31/cjcp1708181 [6] M. A. Hines and P. Guyot-Sionnest, J. Phys. Chem. 100, 468 (1996). doi: 10.1021/jp9530562 [7] H. Shen, Q. Gao, Y. Zhang, Y. Lin, Q. Lin, Z. Li, L. Chen, Z. Zeng, X. Li, Y. Jia, S. Wang, Z. Du, L. S. Li, and Z. Zhang, Nature Photon. 13, 192 (2019). doi: 10.1038/s41566-019-0364-z [8] M. Han, X. Gao, J. Z. Su, and S. Nie, Nat. Biotechnol. 19, 631 (2001). doi: 10.1038/90228 [9] W. Chen, X. Lu, F. Fan, and J. Du, Nano Lett. 21, 7732 (2021). doi: 10.1021/acs.nanolett.1c02547 [10] Y. S. Park, J. Roh, B. T. Diroll, R. D. Schaller, and V. I. Klimov, Nat. Rev. Mater. 6, 382 (2021). doi: 10.1038/s41578-020-00274-9 [11] F. Fan, O. Voznyy, R. P. Sabatini, K. T. Bicanic, M. M. Adachi, J. R. McBride, K. R. Reid, Y. S. Park, X. Li, A. Jain, R. Quintero-Bermudez, M. Saravanapavanantham, M. Liu, M. Korkusinski, P. Hawrylak, V. I. Klimov, S. J. Rosenthal, S. Hoogland, and E. H. Sargent, Nature 544, 75 (2017). doi: 10.1038/nature21424 [12] B. Tang, G. Li, X. Ru, Y. Gao, Z. Li, H. Shen, H. Yao, F. Fan, and J. Du, Nano Lett. (2022). [13] C. Dang, J. Lee, C. Breen, J. S. Steckel, S. Coe-Sullivan, and A. Nurmikko, Nat. Nanotechnol. 7, 335 (2012). doi: 10.1038/nnano.2012.61 [14] V. I. Klimov, A. A. Mikhailovsky, S. Xu, A. Malko, J. A. Hollingsworth, C. A. Leatherdale, H. J. Eisler, and M. G. Bawendi, Science 290, 314 (2000). doi: 10.1126/science.290.5490.314 [15] J. Zhao, Y. Yan, Z. Gao, Y. Du, H. Dong, J. Yao, and Y. S. Zhao, Nat. Commun. 10, 870 (2019). doi: 10.1038/s41467-019-08834-6 [16] S. Komura, K. Okuda, K. Onoda, and H. Kijima, J. Soc. Inf. Disp. 29, 17 (2021). doi: 10.1002/jsid.950 [17] F. Schütt, M. Zapf, S. Signetti, J. Strobel, H. Krüger, R. Röder, J. Carstensen, N. Wolff, J. Marx, T. Carey, M. Schweichel, M.-I. Terasa, L. Siebert, H. K. Hong, S. Kaps, B. Fiedler, Y. K. Mishra, Z. Lee, N. M. Pugno, L. Kienle, A. C. Ferrari, F. Torrisi, C. Ronning, and R. Adelung, Nat. Commun. 11, 1437 (2020). doi: 10.1038/s41467-020-14875-z [18] M. Karl, J. M. E. Glackin, M. Schubert, N. M. Kronenberg, G. A. Turnbull, I. D. W. Samuel, and M. C. Gather, Nat. Commun. 9, 1525 (2018). doi: 10.1038/s41467-018-03874-w [19] M. K. Choi, J. Yang, T. Hyeon, and D. H. Kim, Npj Flex. Electron. 2, 1 (2018). doi: 10.1038/s41528-017-0014-9 [20] N. M. Idris, M. K. Gnanasammandhan, J. Zhang, P. C. Ho, R. Mahendran, and Y. Zhang, Nat. Med. 18, 1580 (2012). doi: 10.1038/nm.2933 [21] X. Wu, Y. Zhang, K. Takle, O. Bilsel, Z. Li, H. Lee, Z. Zhang, D. Li, W. Fan, C. Duan, E. M. Chan, C. Lois, Y. Xiang, and G. Han, ACS Nano 10, 1060 (2016). doi: 10.1021/acsnano.5b06383 [22] Y. Niu, J. Li, J. Gao, X. Ouyang, L. Cai, and Q. Xu, Nano Res. 14, 3820 (2021). doi: 10.1007/s12274-021-3757-5 [23] Y. C. Chen and X. Fan, Adv. Opt. Mater. 7, 1900377 (2019). doi: 10.1002/adom.201900377 [24] S. C. Glotzer and M. J. Solomon, Nat. Mater. 6, 557 (2007). doi: 10.1038/nmat1949 [25] J. Wang, J. Schwenger, A. Ströbel, P. Feldner, P. Herre, S. Romeis, W. Peukert, B. Merle, and N. Vogel, Sci. Adv. 7, eabj0954 (2021). doi: 10.1126/sciadv.abj0954 [26] F. Montanarella, D. Urbonas, L. Chadwick, P. G. Moerman, P. J. Baesjou, R. F. Mahrt, A. van Blaaderen, T. Stöferle, and D. Vanmaekelbergh, ACS Nano 12, 12788 (2018). doi: 10.1021/acs.chemmater.2c00039 [27] Y. Song, R. Liu, Z. Wang, H. Xu, Y. Ma, F. Fan, O. Voznyy, and J. Du, Sci. Adv. 8, eabl8219 (2022). doi: 10.1126/sciadv.abl8219 [28] S. Christodoulou, G. Vaccaro, V. Pinchetti, F. D. Donato, J. Q. Grim, A. Casu, A. Genovese, G. Vicidomini, A. Diaspro, S. Brovelli, L. Manna, and I. Moreels, J. Mater. Chem. C 2, 3439 (2014). doi: 10.1039/c4tc00280f [29] S. Guttman, Z. Sapir, M. Schultz, A. V. Butenko, B. M. Ocko, M. Deutsch, and E. Sloutskin, Proc. Natl. Acad. Sci. USA 113, 493 (2016). doi: 10.1073/pnas.1515614113 [30] S. X. Qian, J. B. Snow, H. M. Tzeng, and R. K. Chang, Science 231, 486 (1986). doi: 10.1126/science.231.4737.486 [31] J. Wang, G. Liang, and K. Wu, Chin. J. Chem. Phys. 30, 649 (2017). doi: 10.1063/1674-0068/30/cjcp1711206 [32] V. I. Klimov, A. A. Mikhailovsky, D. W. McBranch, C. A. Leatherdale, and M. G. Bawendi, Science 287, 1011 (2000). doi: 10.1126/science.287.5455.1011 [33] M. Cadelano, V. Sarritzu, N. Sestu, D. Marongiu, F. Chen, R. Piras, R. Corpino, C. M. Carbonaro, F. Quochi, M. Saba, A. Mura, and G. Bongiovanni, Adv. Opt. Mater. 3, 1557 (2015). doi: 10.1002/adom.201500229 [34] Q. Hu, L. Zhao, J. Wu, K. Gao, D. Luo, Y. Jiang, Z. Zhang, C. Zhu, E. Schaible, A. Hexemer, C. Wang, Y. Liu, W. Zhang, M. Grätzel, F. Liu, T. P. Russell, R. Zhu, and Q. Gong, Nat. Commun. 8, 15688 (2017). doi: 10.1038/ncomms15688 [35] Y. Li, X. Wang, W. Xue, W. Wang, W. Zhu, and L. Zhao, Nano Res. 12, 785 (2019). doi: 10.1007/s12274-019-2289-8 [36] P. T. Snee, Y. Chan, D. G. Nocera, and M. G. Bawendi, Adv. Mater. 17, 1131 (2005). doi: 10.1002/adma.200401571 [37] H. Chang, Y. Zhong, H. Dong, Z. Wang, W. Xie, A. Pan, and L. Zhang, Light Sci. Appl. 10, 60 (2021). doi: 10.1038/s41377-021-00508-7 [38] Y. Wang, X. Li, J. Song, L. Xiao, H. Zeng, and H. Sun, Adv. Mater. 27, 7101 (2015). doi: 10.1002/adma.201503573 -
下载:
点击查看大图
计量
- 文章访问数: 539
- HTML全文浏览量: 234
- PDF下载量: 78
- 被引次数: 0
