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As a class of electrode materials for electric double-layer capacitors (EDLCs), carbon dots (CDs) are able to enlarge specific surface areas, fabricate hierarchical pores, and graft pseudocapacitiv...

The development of high-performance nickel-zinc (Ni-Zn) alkaline batteries is mainly plagued by short life span and poor rate performance of ZnO anode materials. To improve the cycling stability and rate capability of Ni-Zn batteries, carbon dots (CDs) are employed to construct clustered ZnO-CDs nanocomposites, coating ZnO with protective shells of carbon layers and providing electron paths to enhance conductivity of the nanocomposites. Univalent zinc species are found at the interfaces between CDs derivatives and ZnO, which are embedded in the nanoclusters and protected well by carbon coating. Theoretical calculations show univalent zinc species change the electronic structures of ZnO surface, so as to accelerate the charging process of ZnO anode materials. Such ZnO-CDs derived nanocomposites exhibit excellent rate capability (95.3%, 84.7% and 75.0% of capacity retention rate at 2, 5 and 10 A g−1, respectively) and outstanding cycling stability with 92.0% of capacity retention rate after 5000 cycles, which is far better than ZnO based anodes without the protection of CDs (39.1% retention rate from 1 to 10 A g−1 and 71.6% of capacity retention rate after 500 cycles).

Brightly red fluorescent carbon dots are synthesized hydrothermally and dissolved in diluted hydrochloric acid solution. Such carbon dots exhibit excitation-independent emission at about 620 nm with quantum yield over 10%, which is visible in daylight. After the carbon dots solution is sprayed to the fingerprints on various solid substrates and dried in air, clear fingerprints can be seen under an ultraviolet lamp and stay stable for 1 day. Detailed characterizations suggest that during the drying process, the coffee-ring effect and the electrostatic interactions between the carbon dots and the fingerprint residues prevent the typical aggregation-induced fluorescence quenching of carbon dots.

The amine aldehydes resin-mesoporous materials complex AFC-SBA-15 was synthesized using ordered mesoporous materials SBA-15 as the carrier. The obtained compound was characterized by FT-IR,N2adsorption-desorption and scanning electron microscopy. The compound retained ordered mesoporous structure and the resin polymer coated inside channels and outside surface hole wall. The adsorption behavior was carried out with the presence of EDTA in binary components of Pb (II) and Zn (II). The result showed that with the presence of EDTA, tunable selectivity could be realized.