引入喹喔啉吡唑配位基之二價鉑金屬磷光材料的製備及光物理性質探討

Synthesis and Characterization of Pt(II) Complexes with Quinoxalinyl Pyrazolate Chelates

林彥勳(Yen-Hsun Lin)

指導教授 ： 季昀

國立清華大學/理學院/化學系所/碩士(2021年)

摘要

近紅外光有機發光二極體(near-IR OLED)因為其在醫療、軍事、生物技術上的潛力而受到重視。實驗室在2017年發表的Pt(fprpz)2結構，其最大放射波長(λmax)達到740nm，製作成元件後的最大外部量子效率(EQE)可以達到24%。
　　在本論文中，我們將Pt(fprpz)2中的配位基fprpz共軛延長為fqxpz。並引入picolinic acid (pic)作為ancillary ligand，期望能使放光紅移。
　　合成了一系列具這樣骨架的錯合物後，我們從液態UV-Vis光譜推測錯合物單分子時的發色團位於fqxpz上，且不容易受到pic上的取代基影響。但昇華粉末PL及mechanochormism現象則顯示錯合物在固態時為MMLCT放光，且pic上的取代基可以影響堆疊，進而影響錯合物在固態時放光的光色。
　　最後，蒸鍍薄膜的分析顯示，儘管蒸鍍薄膜的吸收光譜沒有明顯的MMLCT吸收，但放射光譜卻有明顯的MMLCT放光。這是一個有趣且值得探討的現象，但因此而導致的大Stokes shift使的本系列錯合物無法於OLED上有應用。

關鍵字

有機發光二極體 ； 磷光發光材料 ； MMLCT躍遷 ； 近紅外光發光材料 ； 鉑金屬錯合物 ； 平面四邊形錯合物

並列摘要

Near-infrared organic light-emitting diodes (near-IR OLEDs)have attracted much attention for its various applications in many fields such as medical, military, biotechnology, etc. In 2017, our group developed Pt(fprpz)2, a near IR phosphorescent emitting material with an emission peak weavelength (λmax) at 740 nm, and shows 24% EQE after being fabricated into device.
　　To pursue emitters showing longer emission wavelength, we extend the aromatic system of fprpz in Pt(fprpz)2 to fqxpz and synthetized a series of complexes with a framework of Pt(fqxpz)(pic).
　　Analysis of liquid UV-Vis spectrum shows that the chromophores are mainly located at fqxpz and not affected by ancillary ligand when complexs are in monomer state. On the other hand, analysis of solid-state PL spectrum shows MMLCT emission, which indicated a Pt-Pt interaction in solid state.
　　Finally, analysis of vacuum deposition thin film of complexes shows that the complexes show no MMLCT in absorption but show MMLCT in emission. This is an interesting phenomena, but the resulting large stokes shift hinders those complexes in any OLED applications.

並列關鍵字

Orgaic light emitting diode ； phosphor materials ； metal-metal to ligand charge transfer ； near-infrared emitting materials ； square planar complexes

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