| 摘要: | 光致變色分子可藉由光照來改變染料結構與吸收特性進而改變顏色，在外界刺激下可變回原本的顏色，此類分子組裝成DSC可能具有光致變色的特性，可以應用在建築上。本研究以iPr-pyso (2-(propane-2-sulfinylmethyl)-pyridine) 作為釕錯合物的輔助配位基，合成出含Ru-S=O變色單元的化合物PC-Na、PC-Cl及PC-NCS。以配位能力較強的分子(如: DMSO)作為測量光致變色性質的溶劑，在照光後原本輔助配位基會被溶劑分子置換而失去光致變色的能力，故溶劑選擇配位能力較弱之MeOH。在濃度為1⨯10-4 M的MeOH溶液中，經由太陽光模擬器的光源(照射至樣品功率為100 mW/cm2) 照射後，PC-Na在照光1分鐘內變色明顯，從橘色變成深紅色，變色原因可能與配位點從(Ru-S=O)變成(Ru-O=S)有關；放置暗處1天後顏色則從深紅色變回橘色，變色原因可能是配位點從(Ru-O=S)變回(Ru-S=O)；PC-NCS需要照光至8分鐘，顏色從橘色變深紅色，變色可能的原因除了與配位點從(Ru-S=O)變成(Ru-O=S)外，也涉及到配位基(NCS-)的斷裂；PC-Cl的顏色則需要照光至20分鐘，才從淡褐色變較深的褐色，變色可能的原因為Cl-的斷裂，PC-NCS和PC-Cl在暗處顏色皆變不回去。其中變色後較吸收可逆性較高的染料為PC-Na，PC-Na在1次循環後與未照光的吸收度差值為6%，光致變色的反應可進行2次以上，將PC-Na組裝成元件後，光電轉換效率為2.91%，照光20分鐘後可增加至3.62%，靜置在暗處會減少為2.82%。;Photochromic molecules can undergo structural and absorption changes upon light irradiation, resulting in a color change, and can revert to their original color when exposed to external stimuli. When such molecules are assembled into DSCs, they may exhibit photochromic properties and can be applied in architecture. In this study, iPr-pyso (2-(propane-2-sulfinylmethyl)-pyridine) was used as an ancillary ligand for ruthenium complexes to synthesize compounds PC-Na, PC-Cl, and PC-NCS containing Ru–S=O photochromic units. When a strong coordinating solvent (e.g., DMSO) is used to measure photochromic properties, the ancillary ligand is replaced by solvent molecules upon irradiation, leading to the loss of photochromic ability. Therefore, MeOH, a weaker coordinating solvent, was chosen. In a 1⨯10⁻⁴ M MeOH solution, under irradiation from a solar simulator (100 mW/cm² at the sample), PC-Na exhibited a distinct color change within 1 minute, shifting from orange to dark red. The color change may be related to the coordination site switching from (Ru–S=O) to (Ru–O=S). When left in the dark for 1 day, the color reverted from dark red to orange, possibly due to the coordination site switching back from (Ru–O=S) to (Ru–S=O). PC-NCS required 8 minutes of irradiation for its color to change from orange to dark red, likely due not only to the coordination site change (Ru–S=O → Ru–O=S) but also to the dissociation of the NCS⁻ ligand. PC-Cl required 20 minutes of irradiation for its color to change from light brown to darker brown, which may be attributed to Cl⁻ dissociation. Unlike PC-Na, both PC-NCS and PC-Cl did not revert to their original colors in the dark. Among these, PC-Na exhibited the highest reversibility in absorption after coloration, with only a 6% difference in absorbance between the irradiated and non-irradiated states after one cycle. The photochromic reaction could proceed for more than two cycles. When PC-Na was assembled into a device, its power conversion efficiency was 2.91%, which increased to 3.62% after 20 minutes of irradiation, but decreased to 2.82% after being left in the dark. |
