Remarkable Enhancement in the Nonlinear Optical Responses of Porphyrins Realized by Combination with Polyoxometalates via Covalent Bonding: A Case Study

详细信息    查看全文

• 作者：Sadaf ul Hassan ; Yunshan Zhou ; Lijuan Zhang ; Zonghai Shi ; Di Yang ; Hafiz Muhammad Asif ; Ningning Qu
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：April 14, 2016
• 年：2016
• 卷：120
• 期：14
• 页码：7757-7766
• 全文大小：614K
• 年卷期：0
• ISSN：1932-7455

文摘

Integrating polyoxometalates into porphyrin moieties via covalent bond is expected to be a new approach to tune and enhance the nonlinear optical responses of porphyrins. The effectiveness and efficiency of this proposal has been examined and witnessed by studying two new hybrid compounds as a prototype, namely, (Bu₄N)₄K₂[{C₅₂H₃₂N₅O₂Zn}HNC(CH₂O)₃P₂V₃W₁₅O₅₉]·2(C₄H₉NO) (1) and (Bu₄N)₄K₂[{C₅₂H₃₄N₅O₂}HNC(CH₂O)₃P₂V₃W₁₅O₅₉]·3(C₄H₉NO) (2), in which porphyrins acting as electron donor and Dawson type polyoxometalate acting as electron acceptor are connected via short tether through covalent bond. The new compounds are systematically characterized by means of elemental analyses, FT-IR, ¹H NMR, ESI-MS, TG/DTA, UV–vis, fluorescence emission spectra, and cyclic voltammetry measurement. Remarkably, great enhancement in reverse saturation absorption is achieved in 1 and 2 which is ca. 1 order of magnitude greater than their individual reactants. Additionally, optical-limiting thresholds are obtained being 0.484 J/cm² for 1 and 0.501 J/cm² for 2, respectively, implying their high potential as low-power optical-limiting materials.