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Mixed-Flow Design for Microfluidic Printing of Two-phase Polymer Semiconductor Systems



Subhrangsu Mukherjee, Gang Wang, Liang-Wen Feng, Wei Huang, Yao Chen, Dengke Shen, Binghao Wang, Joseph Strzalka, Zheng Ding, Ferdinand Melkonyan, Jinhui Yan, J. Fraser Stoddart, Simone Fabiano, Dean DeLongchamp, Meifang Zhu, Antonio Facchetti, Tobin Marks


The rational creation of two-phase conjugated polymer systems with high levels of phase purity in each phase is challenging but crucial for realizing printed soft matter electronics. Here we report a mixed-flow microfluidic printing (MFMP) approach for two-phase π- polymer systems that significantly elevates phase purity in bulk-heterojunction solar cells and thin-film transistors. MFMP integrates laminar and extensional flows using a specially microstructured shear blade, designed with fluid flow simulation tools to tune the flow patterns and induce shear, stretch, and push-out effects. This optimizes polymer conformation and semiconducting blend order as assessed by AFM, TEM, GIWAXS, R-SoXS, photovoltaic response, and field effect mobility. For printed all-polymer (J51:N2200) solar cells this approach enhances short-circuit currents and fill factors, with power conversion efficiency increasing from 5.20 % for conventional blade-coating to 7.80 % for MFMP. Moreover, the performance of mixed polymer ambipolar (P3HT:N2200) and semiconducting:insulating polymer unipolar (N2200:polystyrene) transistors is similarly enhanced, underscoring versatility for two- phase π-polymer systems. Mixed flow designs offer new modalities for achieving high-performance organic opto-electronics via innovative printing methodologies.


Mixed-flow Design, Phase Purity, Two-phase, Semiconductor Polymer, Printed Electronics


Mukherjee, S. , Wang, G. , Feng, L. , Huang, W. , Chen, Y. , Shen, D. , Wang, B. , Strzalka, J. , Ding, Z. , Melkonyan, F. , Yan, J. , Stoddart, J. , Fabiano, S. , DeLongchamp, D. , Zhu, M. , Facchetti, A. and Marks, T. (2020), Mixed-Flow Design for Microfluidic Printing of Two-phase Polymer Semiconductor Systems, PNAS, [online], (Accessed April 14, 2024)
Created July 9, 2020, Updated March 5, 2023