2 research outputs found
Engineered Fabrication of Hierarchical Frameworks with Tuned Pore Structure and N,O-Co-Doping for High-Performance Supercapacitors
A series of multiheteroatom
porous carbon frameworks (MPCFs) is prepared successfully from the
trimerization of cyano groups of our designed and synthesized 4,4′-(4-oxophthalazine-1,3Â(4<i>H</i>)-diyl)Âdibenzonitrile monomers and subsequent ionothermal
synthesis. Benefiting from the molecular engineering strategy, the
obtained MPCFs framework show a homogeneous distribution of nitrogen
and oxygen heteroatoms at the atomic level, confirmed by the transmission
electron microscopy mapping intuitively, thereby ensuring the stability
of electrical properties. The supercapacitor with the obtained MPCFs@700
as the electrode exhibits a high energy density of 65 Wh kg<sup>–1</sup> at 0.1 A g<sup>–1</sup>, with excellent long cycle life and
cycle stability (98% capacitance retention for 10 000 cycles
in 1-butyl-3-methylimidazolium tetrafluoroborate). Another two electrolyte
systems employed also demonstrate the delightful results, showing
a 112% capacitance retention for 30 000 cycles in 1 M H<sub>2</sub>SO<sub>4</sub> and a 95% capacitance retention for 30 000
cycles in tetraethylammonium tetrafluoroborate in an acetonitrile
solution. Moreover, the successful preparation of MPCFs provides new
insights into the fabrication of electrode materials intrinsically
containing nitrogen and oxygen in the frameworks for readily available
components through a facile routine
DataSheet1_Direct preparation of solid carbon dots by pyrolysis of collagen waste and their applications in fluorescent sensing and imaging.DOCX
The fluorescent carbon dots (CDs) have found their extensive applications in sensing, bioimaging, and photoelectronic devices. In general terms, the synthesis of CDs is straight-forward, though their subsequent purification can be laborious. Therefore, there is a need for easier ways to generate solid CDs with a high conversion yield. Herein, we used collagen waste as a carbon source in producing solid CDs through a calcination procedure without additional chemical decomposition treatment of the raw material. Considering a mass of acid has destroyed the original protein macromolecules into the assembled structure with amino acids and peptide chains in the commercial extraction procedure of collagen product. The residual tissues were assembled with weak intermolecular interactions, which would easily undergo dehydration, polymerization, and carbonization during the heat treatment to produce solid CDs directly. The calcination parameters were surveyed to give the highest conversion yield at 78%, which occurred at 300°C for 2 h. N and S atomic doping CDs (N-CDs and S-CDs) were synthesized at a similar process except for immersion of the collagen waste in sulfuric acid or nitric acid in advance. Further experiments suggested the prepared CDs can serve as an excellent sensor platform for Fe3+ in an acid medium with high anti-interference. The cytotoxicity assays confirmed the biosafety and biocompatibility of the CDs, suggesting potential applications in bioimaging. This work provides a new avenue for preparing solid CDs with high conversion yield.</p