排序方式： 共有6条查询结果，搜索用时 0 毫秒
1
1.
Kakaraparthi Kranthiraja Seonha Kim Changyeon Lee Kumarasamy Gunasekar Vijaya Gopalan Sree Bhoj Gautam Kenan Gundogdu Sung‐Ho Jin Bumjoon J. Kim 《Advanced functional materials》2017,27(29)
The performance of all‐polymer solar cells (all‐PSCs) is often limited by the poor exciton dissociation process. Here, the design of a series of polymer donors ( P1 – P3 ) with different numbers of fluorine atoms on their backbone is presented and the influence of fluorination on charge generation in all‐PSCs is investigated. Sequential fluorination of the polymer backbones increases the dipole moment difference between the ground and excited states (Δµge) from P1 (18.40 D) to P2 (25.11 D) and to P3 (28.47 D). The large Δµge of P3 leads to efficient exciton dissociation with greatly suppressed charge recombination in P3 ‐based all‐PSCs. Additionally, the fluorination lowers the highest occupied molecular orbital energy level of P3 and P2 , leading to higher open‐circuit voltage (VOC). The power conversion efficiency of the P3 ‐based all‐PSCs (6.42%) outperforms those of the P2 and P1 (5.00% and 2.65%)‐based devices. The reduced charge recombination and the enhanced polymer exciton lifetime in P3 ‐based all‐PSCs are confirmed by the measurements of light‐intensity dependent short‐circuit current density (JSC) and VOC, and time‐resolved photoluminescence. The results provide reciprocal understanding of the charge generation process associated with Δµge in all‐PSCs and suggest an effective strategy for designing π‐conjugated polymers for high performance all‐PSCs. 相似文献
2.
3.
Kakaraparthi Kranthiraja;Waner He;Hao-Wei Yu;Zhen Feng;Naoya Nozaki;Hidetoshi Matsumoto;Ming-Hsuan Yu;Yong Li;Sergei Manzhos;Mats R. Andersson;Chu-Chen Chueh;Tsuyoshi Michinobu;Prashant Sonar; 《Solar RRL》2024,8(14):2400185
While dual-acceptor-type conjugated polymers have witnessed a great success in organic field-effect transistors (OFETs), their potential multifunctionality in other optoelectronic devices has been overlooked. Herein, three conjugated polymers (DPPF-BDD, DPPT-BDD, and DPPSe-BDD) comprising furan/thiophene/selenophene-flanked diketopyrrolopyrrole (DPP) and dioxo-benzodithiophene (BDD) as repeating units are designed, synthesized, and characterized. Modulating the chalcogen on DPP flank shows an impact on dual-acceptor polymer optoelectronic properties. Subsequently, the potential of these polymers in both OFETs and perovskite solar cells (PSCs) either as semiconductors or as passivation materials, respectively, is investigated. Interestingly, DPPF-BDD, DPPT-BDD, and DPPSe-BDD show ambipolar behavior in vacuum with hole (μh) and electron (μe) mobilities of 0.0263/0.0223, 0.0187/0.0123, and 0.0070/0.0051 cm2 V−1 s−1, respectively. Upon doping tetrabutylammonium iodide into DPPF-BDD, DPPT-BDD, and DPPSe-BDD polymers, the respective OFETs show relatively higher μh and μe (0.0389/0.0503; 0.0289/0.0259; 0.0058/0.0156 cm2 V−1 s−1) than the undoped polymer OFETs. Furthermore, DPPF-BDD-, DPPT-BDD-, and DPPSe-BDD-incorporated (in the antisolvent treatment and PCBM electron transport layer) PSCs display maximum power conversion efficiency of 23.48%, 22.85%, and 23.35%, respectively, surpassing the control device (22.83%), which is benefited from the perovskite surface passivation and the charge extraction improvement. Overall, a new class of multifunctional DPP-based dual-acceptor-type polymers that are highly compatible with OFETs and high-performance PSCs is presented. 相似文献
4.
Despite the capacity of conjugated materials for enhanced power conversion efficiency (PCE) of organic photovoltaics (OPV), a comprehensive survey of unexplored materials is beyond the reach of most researchers’ resources. In such instances, a data-driven approach using machine learning (ML) is an efficient alternative; however, bridging the gap between experimental observations and data science requires a number of refinements. In this investigation, using a random forest model based on an experimental dataset, a high correlation coefficient of 0.85 is achieved for the ML of polymer and non-fullerene small molecule acceptor OPVs and performed virtual screening of 200,932 conjugated polymers generated by the combinatorial coupling of donor and acceptor units. Further, to evaluate the effectiveness of the ML model, a series of conjugated polymers (based on benzodithiophene and thiazolothiazole) were designed, synthesized, and characterized with different alkyl chains. Among these, PBDTTzEH:IT-4F showed a PCE of 10.10%, which is in good correspondence with ML predictions with respect to the choice of alkyl chains. Thus, the current study demonstrates how ML can be utilized for developing OPVs using a relatively small number of experimental data points (566) and screening numerous molecular structures. 相似文献
5.
6.
Kakaraparthi Kranthiraja Kumarasamy Gunasekar Hyunji Kim An‐Na Cho Nam‐Gyu Park Seonha Kim Bumjoon J. Kim Ryosuke Nishikubo Akinori Saeki Myungkwan Song Sung‐Ho Jin 《Advanced materials (Deerfield Beach, Fla.)》2017,29(23)
Perovskite solar cells (PSCs) and organic solar cells (OSCs) are promising renewable light‐harvesting technologies with high performance, but the utilization of hazardous dopants and high boiling additives is harmful to all forms of life and the environment. Herein, new multirole π‐conjugated polymers (P1–P3) are developed via a rational design approach through theoretical hindsight, further successfully subjecting them into dopant‐free PSCs as hole‐transporting materials and additive‐free OSCs as photoactive donors, respectively. Especially, P3‐based PSCs and OSCs not only show high power conversion efficiencies of 17.28% and 8.26%, but also display an excellent ambient stability up to 30 d (for PSCs only), owing to their inherent superior optoelectronic properties in their pristine form. Overall, the rational approach promises to support the development of environmentally and economically sustainable PSCs and OSCs. 相似文献
1