Ultrastable and ultrasensitive pH-switchable carbon dots with high quantum yield for water quality identification, gluco
- PDF / 2,324,952 Bytes
- 7 Pages / 612 x 808 pts Page_size
- 58 Downloads / 152 Views
Ultrastable and ultrasensitive pH-switchable carbon dots with high quantum yield for water quality identification, glucose detection, and two starch-based solid-state fluorescence materials Daiyong Chao1,2, Jinxing Chen2, Qing Dong1,2, Weiwei Wu2, Desheng Qi1, and Shaojun Dong1,2 () 1 2
College of Chemistry, Jilin University, Changchun 130012, China State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2020 Received: 03 May 2020 / Revised: 29 June 2020 / Accepted: 30 June 2020
ABSTRACT It is attractive and encouraging to develop new fluorescent carbon dots (CDs) with excellent optical properties and promising applications prospects. Herein, highly-efficient green emissive CDs (m-CDs) with a high quantum yield (QY) of 71.7% in water are prepared through a facile solvothermal method. Interestingly, the m-CDs exhibit excellent fluorescence stability in the pH range of 1–9. However, the fluorescence intensity of the m-CDs is almost completely quenched as the pH is increased from 9 to 10. The mechanism of the unique pH-responsive behavior is discussed in detail and a plausible mechanism is proposed. Owing to the unique pH-responsive behavior, the m-CDs are used as a on-off fluorescent probe for water quality identification. By combining the reversible pH-ultrasensitive optical properties of the m-CDs in the pH range of 9−10 with the glucose oxidase-mimicking (GOx-mimicking) ability of Au nanoparticles (AuNPs), glucose can be quantitatively detected. Finally, two environment-friendly starch-based solid-state fluorescence materials (powder and film) are developed through green preparation routes.
KEYWORDS carbon dot, high quantum yield, pH-ultrasensitive optical properties, water quality identification, glucose detection, solid-state fluorescence materials
1
Introduction
Semiconductor quantum dots (QDs), as a typical fluorescent nanomaterial with size-dependent optical properties, have been extensively investigated in the past decades [1, 2]. However, the complicated preparation procedures and the known toxicity of QDs have impeded their practical applications. The emerging carbon dots (CDs) are considered to be ideal substitutes for traditional QDs owing to their good photostability, high water solubility, less toxicity, excellent biocompatibility, and facile preparation [3–6]. These merits of CDs have led to their applications in many fields, such as bioimaging [7, 8], catalysis [9], sensors [10, 11], and optoelectronic devices [7, 12]. So far, researchers have proposed numerous methods to prepare the CDs with various photoluminescence (PL) colors, ranging from top-down to bottom-up strategies using thousands of starting materials [13]. Moreover, the development of high-quantumyield fluorescent CDs through simple methods has been an intense research topic for years, as high quantum yield (QY) is one of the pivotal prerequisites for nea
Data Loading...
