Search

Photocatalytic mechanism proposed for PCN-BTD 008 copolymer sample for overall water splitting under the illumination. [Display omitted] • BTD integrated copolymer (PCN-BTD) via thermal process. • An incorporation of BTD is reinforced by DFT data. • Eight-time enhanced HER of PCN-BTD 008 (744.2 μmol/h) than pure PCN (88.2 μmol/h). • The OER, generates 0.2 μmol/h−1 and 1.6 μmol/h−1 for PCN, while PCN-BTD 008 yield 2.2 μmol/h−1 (visible) and 14.8 μmol/h−1 (non-visible) respectively. Well-organized water splitting semiconducting photocatalyst is an important concept, but stimulating aimed at decisive energy and environmental emergencies. In this context, visible light-based photocatalytic water splitting with low-dimensional semiconducting materials is proposed to produce sustainable energy. Here we optimized the sequential of organic electron-rich heterocyclic monomer namely benzothiadiazole (BTD) quenched within polymeric carbon nitride (PCN) semiconductor via copolymerization, thereby assembling a sanctum of donor-π-acceptor (D-π-A) photocatalysts. The selection of BTD is based on the benzene ring, which consequently anticipating a π cross-linker unit for hydrogen and oxygen evolution. A hydrogen evolution rates (HER) of 88.2 μmol/h for pristine PCN and 744.2 μmol/h for PCN-BTD 008 (eight times higher than pure PCN) are observed. Additionally, a remarkable apparent quantum yield (AQY) of about 58.6% at 420 nm has been observed for PCN-BTD 008. Likewise, the oxygen evolution rate (OER) data reflect the generation of 0.2 μmol/h1 (visible) and 1.6 μmol/h1 (non-visible) for pure PCN. Though, OER of PCN-BTD 008 is found to be 2.2 μmol/h1 (visible) and 14.8 μmol/h1 (non-visible), which are economically better than pure PCN. As such, the results show an important step toward modifying the design and explain a vital part of the D-π-A scheme at a balanced theme for fruitful photocatalysts intended for future demand. [ABSTRACT FROM AUTHOR]

Doped carbon dots have attracted great attention from researchers across disciplines because of their unique characteristics, such as their low toxicity, physiochemical stability, photostability, and outstanding biocompatibility. Nitrogen is one of the most commonly used elements for doping because of its sizeable atomic radius, strong electronegativity, abundance, and availability of electrons. This distinguishes them from other atoms and allows them to perform distinctive roles in various applications. Here, we have reviewed the most current breakthroughs in nitrogen-doped CDs (N-CDs) for fluorescent sensor applications in the last five years. The first section of the article addresses several synthetic and sustainable ways of making N-CDs. Next, we briefly reviewed the fluorescent features of N-CDs and their sensing mechanism. Furthermore, we have thoroughly reviewed their fluorescent sensor applications as sensors for cations, anions, small molecules, enzymes, antibiotics, pathogens, explosives, and pesticides. Finally, we have discussed the N-CDs' potential future as primary research and how that may be used. We hope that this study will contribute to a better understanding of the principles of N-CDs and the sensory applications that they can serve. [Display omitted] • Extensive overview of fluorescence N-CDs for optical sensor applications. • The possible processes underlying the PL origins of N-CDs were outlined. • Discussed the effects of various dopants on the photophysical characteristics of CDs. • Use of N-CDs for detecting ions, small compounds, and pharmaceuticals was described. [ABSTRACT FROM AUTHOR]