{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,5]],"date-time":"2026-09-05T16:59:59Z","timestamp":1788627599382,"version":"build-2803163510"},"reference-count":39,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,8]],"date-time":"2023-03-08T00:00:00Z","timestamp":1678233600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Korea government (MSIT)","award":["NRF-2020M1A2A2080746"],"award-info":[{"award-number":["NRF-2020M1A2A2080746"]}]},{"name":"Korea government (MSIT)","award":["NRF-2021M3D1A2049323"],"award-info":[{"award-number":["NRF-2021M3D1A2049323"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Organic solar cells (OSCs) demonstrating high power conversion efficiencies have been mostly fabricated using halogenated solvents, which are highly toxic and harmful to humans and the environment. Recently, non-halogenated solvents have emerged as a potential alternative. However, there has been limited success in attaining an optimal morphology when non-halogenated solvents (typically o-xylene (XY)) were used. To address this issue, we studied the dependence of the photovoltaic properties of all-polymer solar cells (APSCs) on various high-boiling-point non-halogenated additives. We synthesized PTB7-Th and PNDI2HD-T polymers that are soluble in XY and fabricated PTB7-Th:PNDI2HD-T-based APSCs using XY with five additives: 1,2,4-trimethylbenzene (TMB), indane (IN), tetralin (TN), diphenyl ether (DPE), and dibenzyl ether (DBE). The photovoltaic performance was determined in the following order: XY + IN &lt; XY + TMB &lt; XY + DBE \u2264 XY only &lt; XY + DPE &lt; XY + TN. Interestingly, all APSCs processed with an XY solvent system had better photovoltaic properties than APSCs processed with chloroform solution containing 1,8-diiodooctane (CF + DIO). The key reasons for these differences were unraveled using transient photovoltage and two-dimensional grazing incidence X-ray diffraction experiments. The charge lifetimes of APSCs based on XY + TN and XY + DPE were the longest, and their long lifetime was strongly associated with the polymer blend film morphology; the polymer domain sizes were in the nanoscale range, and the blend film surfaces were smoother, as the PTB7-Th polymer domains assumed an untangled, evenly distributed, and internetworked morphology. Our results demonstrate that the use of an additive with an optimal boiling point facilitates the development of polymer blends with a favorable morphology and can contribute to the widespread use of eco-friendly APSCs.<\/jats:p>","DOI":"10.3390\/polym15061354","type":"journal-article","created":{"date-parts":[[2023,3,9]],"date-time":"2023-03-09T01:35:37Z","timestamp":1678325737000},"page":"1354","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Critical Role of Non-Halogenated Solvent Additives in Eco-Friendly and Efficient All-Polymer Solar Cells"],"prefix":"10.3390","volume":"15","author":[{"given":"Saeah","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Chemistry & Nano Science, Ewha University, Seoul 03760, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huijeong","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0946-2274","authenticated-orcid":false,"given":"Myeongjae","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Korea University, Seoul 02841, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyeseung","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Chemistry & Nano Science, Ewha University, Seoul 03760, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yukyung","family":"Shin","sequence":"additional","affiliation":[{"name":"Department of Chemistry & Nano Science, Ewha University, Seoul 03760, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seul","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0115-8112","authenticated-orcid":false,"given":"Kyungkon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry & Nano Science, Ewha University, Seoul 03760, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Myung Hwa","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry & Nano Science, Ewha University, Seoul 03760, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyungwon","family":"Kwak","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Korea University, Seoul 02841, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4982-6343","authenticated-orcid":false,"given":"BongSoo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea"},{"name":"Graduate School of Semiconductor Materials and Device Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea"},{"name":"Graduate School of Carbon Neutrality, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1701791","DOI":"10.1002\/aenm.201701791","article-title":"Flexible and Semitransparent Organic Solar Cells","volume":"8","author":"Li","year":"2018","journal-title":"Adv. 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