Self-Assembly of Poly(ethyleneimine)-Modified g-C3N4 Nanosheets with Lysozyme Fibrils for Chromium Detoxification
| Autor: | Shiuh-Jen Jiang, A. Santhana Krishna Kumar, Emmanuvel Arputharaj, Hans-Uwe Dahms, Yeou-Lih Huang, Wei-Lung Tseng |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Aqueous solution
Chemistry Graphitic carbon nitride chemistry.chemical_element Langmuir adsorption model 02 engineering and technology Surfaces and Interfaces 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences 0104 chemical sciences Chromium symbols.namesake chemistry.chemical_compound Adsorption Physisorption Specific surface area Electrochemistry symbols General Materials Science Freundlich equation 0210 nano-technology Spectroscopy Nuclear chemistry |
| Zdroj: | Langmuir. 37:7147-7155 |
| ISSN: | 1520-5827 0743-7463 |
| DOI: | 10.1021/acs.langmuir.1c00716 |
| Popis: | We disclose a straightforward approach to fabricate nanocomposites for efficient capture of Cr(VI) from an aqueous solution through the self-assembly of poly(ethyleneimine)-modified graphitic carbon nitride nanosheets (PEI-g-C3N4 NSs) and lysozyme fibrils (LFs). The as-made PEI-g-C3N4 NSs@LFs exhibited mesoporous structures with a high specific surface area of 39.6 m2 g-1, a large pore volume of 0.25 cm3 g-1, several functional groups (e.g., -N, -NH, -NH2, and -COOH), and a zero-point charge at pH 9.1. These merits allow the PEI-g-C3N4 NSs@LFs to further enhance their physical adsorption and electrostatic attraction with the negatively charged Cr(VI) species of HCrO4- and CrO42-, which is beneficial for the uptake of Cr(VI), >80%, from an aqueous solution in a wide pH range. Interestingly, X-ray photoelectron spectra indicate that the PEI-g-C3N4 NSs@LFs converted Cr(VI) to Cr(III) through visible-light-induced photoreduction. The adsorption of Cr(VI) on the surface of PEI-g-C3N4 NSs@LFs was found to obey the Freundlich isotherm model, signifying that they have a heterogeneous surface for the multilayer uptake of Cr(VI). In contrast, the PEI-g-C3N4 NSs and LFs as Cr(VI) adsorbents followed the Langmuir isotherm model. Adsorption kinetic studies showed that the uptake of Cr(VI) through the PEI-g-C3N4 NSs@LFs was highly correlated with a pseudo-first-order model, suggesting that physisorption dominates the interaction of Cr(VI) and the PEI-g-C3N4 NSs@LFs. In real-life applications, the PEI-g-C3N4 NSs@LFs were used for the detoxification of the total chromium in the industrial effluent and sludge samples. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|