The search of new H2 evolution systems avoiding fossil sources and their mechanisms is a priority in the 21st century society. Hydrolysis of tetrahydroxydiboron (TDB), a current borylation source in the literature, is used here for H2 evolution for the first time. It is catalyzed by graphene quantum dot-stabilized nanoparticles (NPs). With RhNP- or PtNP-catalyzed reactions, D2 formation from D2O confirms that water is the only hydrogen source. Kinetic isotopic effects yield k H/k D = 5.91 and 4.18, strongly suggesting double water O–H bond cleavage on the NP surface in the rate-limiting step. The most efficient catalysts are the RhNP and PtNP (total turnover frequencies: 3658 and 4603 molH2 ·molcat –1·min–1, respectively). The order of catalytic activity is as follows: PtNP > RhNP > AuNP > PdNP > IrNP > RuNP, and a catalytic mechanism of TDB hydrolysis is proposed.

Fabrication of graphene quantum dots (GQDs) often requires strong acids or organic solvents, and their green synthesises on sustainable routes still face challenges. Herein, an eco‐friendly synthetic process has been developed, in which the natural polymer cellulose has been utilized as a new precursor for the first time. The reaction system is only composed of cellulose and water, in absence of any other chemical reagents. Moreover, the products contain only GQDs, carbide precipitates, and water, leading to easy separation and avoiding complicated post‐processes. In addition, the synthetic mechanism is presented that the formation process of GQDs consists of the first hydrolyzation and the following cyclic condensation. With highly photoluminescent (PL) properties, favourable hydrophilicity, low cytotoxicity and excellent biocompatability, the as‐synthesized GQDs have been successfully applied in bioimaging. This work not only develops a sustainable route for the green synthesis of GQDs, but also finds a renewable resource as the raw material, which significantly facilitates the extensive applications of GQDs in biological fields.

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A new Light‐Up fluorescent probe (FA‐P) for detection of formaldehyde was designed and synthesized based on the donor‐excited photo induced electron transfer (d‐PeT) process. The probe FA‐P was constructed by integrating a benzothiazole derivatives as the fluorescent skeleton and homoallylamino group as the specific recognition site. It showed the unique advantages of easy‐preparation, and excellent selectivity response toward formaldehyde. Besides, The probe FA‐P can not only detect formaldehyde gas through the prepared test paper, but also detect formaldehyde in serum solution.

Graphene quantum dots (GQDs) have aroused widespread attention because of their remarkable properties and potential applications. Herein, we discuss both the top-down and bottom-up strategies for the synthesis of GQDs. Different processes are presented to study their characteristics and the influence on the final properties of GQDs. The respective advantages and disadvantages of these methods are summarized. With regard to some important or novel ones, mechanisms are proposed for reference. In addition, the application of GQDs in biosensors is highlighted in detail. At last, we put forward some problems to be solved and give a brief prospect in their future developments. This review is very useful for quickly gaining knowledge and experience for synthesizing GQDs and designing the related novel biosensors.

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In recent years, polymer/graphene nanocomposites have attracted much attention because of their wide applications in many fields, such as chemistry, physics, materials and electronics. In this review, the preparation methods of polymer/graphene nanocomposites, including solution blending, melt blending and in situ polymerisation, were presented in order to study the relationship between these methods and their final properties. Each method has an influence on the final characteristics of the nanocomposites. Their respective advantages and disadvantages were discussed. Additionally, the potential application research of graphene-reinforced polymer nanocomposites, including supercapacitors, sensors and solar cells was detailed comprehensively. The current review demonstrated that the nanocomposites exhibit superior performances and will be applied as new materials or novel devices. The research direction of polymer/graphene nanocomposites in the future was also predicted.