Khotele Neha, Kalyani N Thejo, Dhoble S J
Department of Physics, Shivaji Science College, Congress Nagar, Nagpur, 440012, India.
Department of Applied Physics, Laxminarayan Institute of Technology, Nagpur, 440033, India.
Luminescence. 2018 Dec;33(8):1415-1422. doi: 10.1002/bio.3565. Epub 2018 Oct 30.
We designed and synthesized a 2-(4-bromophenyl)-1-phenyl-1H-benzimidazole (pbi-Br) ligand, which was then employed to create an innovative phosphorescent cyclometallated iridium(III) (pbi-Br) Ir(acac) metal complex with acetyl acetone as an ancillary ligand using the Suzuki coupling reaction. The complex was then characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectra and thermogravimetric analysis (TGA)/differential thermal analysis (DTA) for structural and thermal analysis, respectively. XRD confirmed its amorphous nature and the FTIR spectrum revealed the molecular structure confirmation of the metal complex. The TGA/DTA curve disclosed its thermal stability up to 310°C. Ultraviolet (UV)-vis absorption and photoluminescence (PL) spectra were measured to explore the photo-physical properties of the (pbi-Br) Ir(acac) complex in basic and acidic media respectively. With the variation in solvent from acidic to basic media, optical absorption peaks blue shifted with variation in optical densities. These results facilitated the calculation of various photo-physical parameters. When excited at 379 nm in the solid state, the synthesized complex gave out a green light emission, peaking at λ = 552 nm. Staggering differences in optical density were observed in the PL spectra of the solvated complex. A Stokes' shift of 7140.45 cm and 7364.94 cm was observed when the complex was solvated in acetic acid and chloroform, respectively. Hence the synthesized iridium metal complex can be considered as promising green emissive material for optoelectronic applications.
我们设计并合成了一种2-(4-溴苯基)-1-苯基-1H-苯并咪唑（pbi-Br）配体，然后利用铃木偶联反应，以乙酰丙酮作为辅助配体，制备了一种创新的磷光环金属化铱(III)（pbi-Br）Ir(acac)金属配合物。随后分别通过X射线衍射（XRD）、傅里叶变换红外（FTIR）光谱和热重分析（TGA）/差示热分析（DTA）对该配合物进行结构和热分析表征。XRD证实了其无定形性质，FTIR光谱揭示了金属配合物的分子结构确认。TGA/DTA曲线显示其热稳定性高达310°C。分别测量了紫外可见吸收光谱和光致发光（PL）光谱，以探究（pbi-Br）Ir(acac)配合物在碱性和酸性介质中的光物理性质。随着溶剂从酸性介质变为碱性介质，光吸收峰随光密度变化发生蓝移。这些结果有助于计算各种光物理参数。当在固态下以379 nm激发时，合成的配合物发出绿色光，峰值在λ = 552 nm处。在溶剂化配合物的PL光谱中观察到光密度的显著差异。当配合物分别溶解在乙酸和氯仿中时，斯托克斯位移分别为7140.45 cm和7364.94 cm。因此，合成的铱金属配合物可被视为用于光电子应用的有前景的绿色发光材料。
