TY - JOUR
T1 - Achieving NIR Emission for Donor-Acceptor Type Platinum(II) Complexes by Adjusting Coordination Position with Isomeric Ligands
AU - Zhang, Youming
AU - Chen, Zhao
AU - Wang, Xin
AU - He, Junjie
AU - Wu, Jiatao
AU - Liu, Haiyang
AU - Song, Jun
AU - Qu, Junle
AU - Chan, Wesley Ting Kwok
AU - Wong, Wai Yeung
PY - 2018/11/19
Y1 - 2018/11/19
N2 - Four platinum(II) complexes Pt-1, Pt-2, Pt-3, and Pt-4 with the isomeric donor-acceptor (D-A) conjugated ligand framework are designed and prepared, and their thermal, photophysical, and electrochemical characteristics investigated. Crystal structures for Pt-1 and Pt-4 are determined with single-crystal X-ray diffraction analysis, showing distorted and nonplanar geometry. Complex Pt-4 exhibits much greater distortion, attributed to the steric interactions between benzothiadiazole and naphthalene. Remarkably different photophysical, electrochemical, and electroluminescent properties are found for these platinum(II) complexes. Photoluminescence wavelengths of these complexes range from 590 to 800 nm with bandgaps of 1.7-2.0 eV. Coordination with [1,2,5]thiadiazolo[3,4-c]pyridine and triphenylamine can enhance D-A interactions, reducing the bandgap and producing near-infrared emission for Pt-3. Organic light-emitting devices (OLEDs) display electroluminescence with emission peaks at 626, 645, 826, and 571 nm, with maximum external quantum efficiencies of 0.13%, 0.04%, 0.49%, and 0.22% for Pt-1, Pt-2, Pt-3, and Pt-4 doped OLEDs, respectively. Thus, adjusting the coordination position with the isomeric conjugation framework ligand is an appropriate strategy to tune the light-emitting properties of platinum complexes in OLEDs.
AB - Four platinum(II) complexes Pt-1, Pt-2, Pt-3, and Pt-4 with the isomeric donor-acceptor (D-A) conjugated ligand framework are designed and prepared, and their thermal, photophysical, and electrochemical characteristics investigated. Crystal structures for Pt-1 and Pt-4 are determined with single-crystal X-ray diffraction analysis, showing distorted and nonplanar geometry. Complex Pt-4 exhibits much greater distortion, attributed to the steric interactions between benzothiadiazole and naphthalene. Remarkably different photophysical, electrochemical, and electroluminescent properties are found for these platinum(II) complexes. Photoluminescence wavelengths of these complexes range from 590 to 800 nm with bandgaps of 1.7-2.0 eV. Coordination with [1,2,5]thiadiazolo[3,4-c]pyridine and triphenylamine can enhance D-A interactions, reducing the bandgap and producing near-infrared emission for Pt-3. Organic light-emitting devices (OLEDs) display electroluminescence with emission peaks at 626, 645, 826, and 571 nm, with maximum external quantum efficiencies of 0.13%, 0.04%, 0.49%, and 0.22% for Pt-1, Pt-2, Pt-3, and Pt-4 doped OLEDs, respectively. Thus, adjusting the coordination position with the isomeric conjugation framework ligand is an appropriate strategy to tune the light-emitting properties of platinum complexes in OLEDs.
UR - http://www.scopus.com/inward/record.url?scp=85056607925&partnerID=8YFLogxK
U2 - 10.1021/acs.inorgchem.8b02220
DO - 10.1021/acs.inorgchem.8b02220
M3 - Journal article
C2 - 30387603
AN - SCOPUS:85056607925
SN - 0020-1669
VL - 57
SP - 14208
EP - 14217
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 22
ER -