Publications by authors named "Yetai Cheng"

We synthesized two highly volatile and low-cost solid additives, PT and TFT. The inclusion of PT and TFT effectively influences the aggregation behavior of D18: L8-BO during the film-forming process. Consequently, PT and TFT-treated D18: L8-BO-based OSCs achieved power conversion efficiencies of 18.

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In this study, we designed and synthesized two NFREAs, 2BTh-3F and 2BTh-CN, incorporating distinct substituents to modulate their electron-withdrawing properties. We meticulously explore the distinct impacts of these substituents on NFREA performance. Our investigation revealed that the introduction of 3,5-difluoro-4-cyanophenyl in 2BTh-CN significantly enhanced electron withdrawal and intramolecular charge transfer, leading to a red-shifted absorption spectrum and optimized energy levels.

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Article Synopsis
  • - This study highlights the importance of carefully shaping the active layer in organic solar cells (OSCs) by blending different molecular weights of polymer donors, specifically D18.
  • - By adding 10% low molecular weight D18 to high molecular weight D18, a new blend called MIX-D18 is formed, which improves exciton diffusion, molecular organization, and overall charge transport within the cell.
  • - The combination of MIX-D18 with the nonfullerene acceptor L8-BO achieves a significant power conversion efficiency of 20.0%, showcasing a promising strategy for boosting OSC performance by leveraging both high and low molecular weight polymers.
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Efficient charge transport and extraction within the active layer plays a major role in the photovoltaic performance of organic solar cells (OSCs). In this work, the spontaneously spreading (SS) process was utilized to achieve sequential deposition of the active layer with a planar heterojunction (PHJ) structure. The SS process avoids the damage of the upper layer solution to the lower layer film by the spin coating process.

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