Precise evaluation of adsorption behavior of cationic porphyrin on monolayer of perovskite-type niobia nanosheet by absorption spectroscopy. (February 2022)

• Record Type: Journal Article
• Authors: Oshima, Momoka; Sano, Keito; Hirade, Yugo; Nakazato, Ryosuke; Ishida, Tamao; Shimada, Tetsuya; Takagi, Shinsuke
• Is Part Of: Journal of physics and chemistry of solids. Volume 161(2022)
• Publication Date: 2022-02
• Subjects: Organic/inorganic complex -- Porphyrin -- Niobia nanosheet -- Semiconductor nanosheet -- Adsorption; Solids -- Periodicals; Solides -- Périodiques; Solids; Periodicals; 530.41
• DOI: 10.1016/j.jpcs.2021.110423
• Languages: English
• ISSNs: 0022-3697

Abstract

Abstract: To evaluate adsorption behavior of organic dyes on nanosheet surface precisely and reproducibly, we are proposing simple method based on absorption spectroscopy. Typical cationic dye, 5, 10, 15, 20-tetrakis (1-methylpyridinium-4-yl) porphyrin (TMPyP), and anionic nanosheet, perovskite-type niobia nanosheet (NNS), were selected as a guest molecule and a host nanosheet, respectively. The λmax of TMPyP was redshifted by an adsorption on the nanosheets. When the relationship between the loading level of TMPyP and absorbance, the clear inflection point was observed at approximately 71% of the amount of TMPyP added to the cation exchange capacity of NNS. A highly linear plots was observed in the absorbance region around this point, indicating that our experimental method can be used to evaluate the adsorption behavior in detail even at very small absorbance in the order of 0.001. The evaluation of the adsorption behavior of dyes on nanosheet monolayers based on absorption spectroscopy is expected to be a universal method to discuss the behavior of dye molecules on solid surfaces in detail. Highlights: Adsorption behavior of TMPyP on NNS was analyzed by the precise, reproducible, and simple absorption measurement method. The absorbance of TMPyP adsorbed on NNS was quantitatively evaluated even at very small absorbance in the order of 0.001. The maximum adsorption amount of TMPyP was estimated to be approximately 71% vs cation exchange capacity on the monolayer NNS. The orientation angle was calculated to be 57° by dichroic absorption spectroscopy.