The phosphate functionalized carbon dots (PCDs) with high biocompatibility and low toxicity can be used as efficient additives for the construction of laccase/PCDs hybrids catalyst. A series of experiments indicated that the activity of laccase/PCDs was higher than that of free laccase (increased by 47.7%). When laccase/PCDs hybrids catalyst was irradiated with visible light (laccase/PCDs-Light), its activity was higher than that of laccase/PCDs hybrids without light irradiation (increased by 92.1%). In the present system, the T1 Cu in laccase was combined with the phosphate group on PCDs, which can increase binding capacity of laccase/PCDs hybrids and substrate. Further, the visible light irradiation increased the donating and accepting electronic capability of the laccase/PCDs hybrids, improving their catalytic activity.

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The Co 3 O 4 @N doped carbon (Co 3 O 4 @N-C) nanocomposites obtained from metal-organic frameworks (MOFs) possess excellent electrocatalytic ability for oxygen reduction reaction (ORR).Catalysis for oxygen reduction reaction (ORR) is at the heart of key renewable-energy technologies owing to their importance to the variety of energy applications including fuel cells, water splitting and metal-air batteries. [1][2][3] And then the ORR electrocatalysts have been one of the major limiting factors for energy conversion efficiency, cost, and stability of these devices. 1 However, the high cost, limited supply, and weak durability of platinum catalysts are the greatest barriers to large-scale industrial applications. Extensive efforts have been devoted to reducing the amounts of Pt-based catalysts used or replacing them. [4][5][6] The ongoing search for new non-precious-metal catalysts with excellent electrocatalytic performances for ORRs has attracted increasing interest. [7][8][9] In this respect, various kinds of nanostructures, such as metal oxide semiconductors, carbon materials, as well as their composite nanostructures (with the merits of metal oxides and carbon materials), have become popular and are regarded as new candidates for the ORR catalysts. Typically, some anion (S, F, P, N)-doped carbon materials, such as anion-doped graphenes, 10-13 carbon spheres, 14 ordered mesoporous graphitic arrays, 15 carbon nanotubes, 16 and mesoporous carbons, 17 have been reported as the potential ORR catalysts. The mixed valence oxides of transition metals with a spinel structure also show ORR catalytic activity under alkaline conditions. 18 Particularly, the spinel type Co 3 O 4 , in which the Co 2+ and Co 3+ ions occupy the tetrahedral and octahedral sites, respectively, can be used as an ORR electrocatalyst in alkaline

Heteroatom (N, P, and B)-codoped nanocarbons (NPBC) with nanoporous morphology are fabricated via a facile one-step pyrolysis method and exhibit good electrocatalytic activity, durability, and selectivity for the oxygen reduction reaction (ORR) in alkaline media. The ORR activity of NPBC is better than single- (nitrogen-doped carbon (NC)) or dual-doped (nitrogen and phosphorus codoped carbon (NPC) or nitrogen and boron codoped carbon (NBC)) catalysts in terms of onset potential and current density. This synthetic approach is efficient and suitable for large-scale fabrication of metal-free carbon-based catalysts.

Carbon dots (CDs) were synthesized by refluxing glucose, as efficient fluorescence probes, which show convenient and sensitive detection of norfloxacin (NOR) over a wide concentration range. It is worth noting that because of the hydrogen bond interactions between the CDs and NOR, the fluorescence intensity of CDs was remarkably enhanced in the presence of NOR, which indicates that CDs are capable of rapid, stable and sensitive determination of NOR. Compared with high-performance liquid chromatography, the fluorescence enhancement method is considerably simpler and faster, and will pave a new way for the determination of NOR.