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.

Mussel-inspired surface modification has received significant interest in recent years because of its simplicity and versatility. The deposition systems are still mainly limited to molecules with catechol chemical structures. In this paper, we report a novel deposition system based on a monophenol, vanillic acid (4-hydroxy-3-methoxybenzoic acid), to fabricate metal–phenolic network coatings on various substrates. The results of the water contact angle and zeta potential reveal that the modified polypropylene microfiltration membrane is underwater superhydrophobic and positively charged, showing applications in oil/water separation and dye removal. Furthermore, the single-face modified Janus membrane is promising in switchable oil/water separation. The results demonstrate a novel example of the metal–monophenolic deposition system, which expands the toolbox of surface coatings and facilitates the understanding of the deposition of phenols.

In an effort to turn waste into wealth, Reactive Red 2 (RR2), a common and refractory organic pollutant in industrial wastewater, has been employed for the first time as precursor...

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The efficient production of H2 from hydrogen‐rich sources, particularly from water, is a crucial task and a great challenge, both as a sustainable energy source and on the laboratory scale for hydrogenation reactions. Herein, a facile and effective synthesis of H2 and D2 from only acid‐ or base‐catalyzed metal‐free hydrolysis of B2(OH)4, a current borylation reagent, has been developed without any transition metal or ligand. Acid‐catalyzed H2 evolution was completed in 4 min, whereas the base‐catalyzed process needed 6 min. The large kinetic isotopic effects for this reaction with D2O, deuteration experiments and mechanistic studies have confirmed that both H atoms of H2 originate from water using either of these reactions. This new, metal‐free catalytic system holds several advantages, such as high efficiency, simplicity of operation, sustainability, economy, and potential further use.

Substrate-independent, chemical-durable, and homogeneous coatings are attracting great interest because of their potential applications in various fields. Surface coatings based on polydopamine and metal–phenol networks have been widely investigated. Phytic acid (PA), a plant-derived compound with six phosphate groups, can coordinate with multivalent ions to generate metal–phytic acid complex coatings. However, the formation of the coatings generally proceeds in a discrete step with a thickness of only about 8 nm via conventional methods. Herein, the continuous assembly of PA–FeIII coatings has been proposed by employing an oxidation-mediated assembly strategy. PA coordinates with an FeII precursor to form soluble complexes, which are then converted into insoluble PA–FeIII aggregates continuously, enabling coating thickness to be controllable and time-dependent. The formation and the kinetic growth process of the coatings are investigated systematically. Highly visible colors induced by the thin-film interference effect have been observed on silicon wafers and tailored by modulating the coating thickness. Moreover, benefiting from the superior chemical resistance and superhydrophilicity of the PA–FeIII coatings, potential applications in membrane modification for oil/water emulsion separation have been demonstrated. The modified membranes exhibit both high flux and separation efficiency. This work provides a feasible route to form effective PA–FeIII coatings and expands the versatile platform of metal–phytic acid surface coatings.

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