A hierarchical, intrafibrillarly mineralized collagen (HIMC) is achieved through a selective mineralization progress in the collagenous gap regions mediated by poly(acrylic acid) with appropriate molecular weight. The associated topographical features directly correlate with nanomechanical heterogeneities of the HIMC to accommodate a broad range of external loads. Moreover, this hierarchically staggered nanostructure provides an optimized microenvironment to improve bone regeneration by instructing host cells.

Gas-sensing applications commonly use nanomaterials (NMs) because of their unique physicochemical properties, including a high surface-to-volume ratio, enormous number of active sites, controllable morphology, and potential for miniaturisation.

Optimising the supported modes of atom or ion dispersal onto substrates, to synchronously integrate high reactivity and robust stability in catalytic conversion, is an important yet challenging area of research. Here, theoretical calculations first show that three-coordinated copper (Cu) sites have higher activity than four-, two- and one-coordinated sites. A site-selective etching method is then introduced to prepare a stacked-nanosheet metal–organic framework (MOF, CASFZU-1)-based catalyst with precisely controlled coordination number sites on its surface. The turnover frequency value of CASFZU-1 with three-coordinated Cu sites, for cycloaddition reaction of CO 2 with epoxides, greatly exceed those of other catalysts reported to date. Five successive catalytic cycles reveal the superior stability of CASFZU-1 in the stacked-nanosheet structure. This study could form a basis for the rational design and construction of highly efficient and robust catalysts in the field of single-atom or ion catalysis.

Copper sulfides (Cu S), are a novel kind of photothermal material exhibiting significant photothermal conversion efficiency, making them very attractive in various energy conversion related devices. Preparing high quality uniform Cu S nanocrystals (NCs) is a top priority for further energy-and sustainability relevant nanodevices. Here, a shape-controlled high quality Cu S NCs synthesis strategy is reported using sulfur in 1-octadecene as precursor by varying the heating temperature, as well as its forming mechanism. The performance of the Cu S NCs is further explored for light-driven water evaporation without the need of heating the bulk liquid to the boiling point, and the results suggest that as-synthesized highly monodisperse NCs perform higher evaporation rate than polydisperse NCs under the identical morphology. Furthermore, disk-like NCs exhibit higher water evaporation rate than spherical NCs. The water evaporation rate can be further enhanced by assembling the organic phase Cu S NCs into a dense film on the aqueous solution surface. The maximum photothermal conversion efficiency is as high as 77.1%.

Graphene quantum dots (GQDs) have been widely used as fluorescence probes to detect metal ions with satisfactory selectivity. However, the diverse chemical structures of GQDs lead to selectivity for multiple metal ions, and this can lead to trouble in the interpretation of selectivity due to the lack of an in depth and systematic analysis. Herein, bare GQDs were synthesized by oxidizing carbon black with nitric acid and used as fluorescent probes to detect metal ions. We found that the specific ability of GQDs to recognize ferric ions relates to the acidity of the medium. Specifically, we demonstrated that the coordination between GQDs and Fe is regulated by the pH of the aqueous GQDs solution. Dissociative Fe can coordinate with the hydroxyl groups on the surface of the GQDs to form aggregates (such as iron hydroxide), which induces fluorescence quenching. A satisfactory selectivity for Fe ions was achieved under relatively acidic conditions; this is because of the extremely small K of ferric hydroxide compared to those of other common metal hydroxides. To directly survey the key parameter for Fe ion specificity, we performed the detection experiment in an environment free of interference from the buffer solution, noninherent groups, and other complex factors. This study will help researchers understand the selectivity mechanisms of GQDs as fluorescence probes for metal ions, which could guide the design of other GQD-based sensor platforms.

Redesigning heterogeneous catalysts so that they can simultaneously integrate the efficiency and durability under reaction environments with respect to gas fuel production, such as hydrogen (H2), oxygen (O2), or carbon monoxide (CO), has proven challenging. In this work, we report the successful template-assisted printing-based assembly of platinum (Pt) nanoparticles (NPs) into striped-pattern (SP) superlattices to produce H2. In comparison to drop-casting flat Pt NPs films, SP superlattices lead to higher mass transference and smaller bubble stretch force, representing a general strategy to improve the efficiency and durability of pre-existed Pt catalysts for the hydrogen evolution reaction (HER), as well as higher current densities than commercial Pt/C, Pt NP films, and many of the other Pt-based or non-Pt-based HER catalysts reported in the literature. The generic nature of template-assisted printing leads to flexibility in the composition, size, and shape of the constituent NPs or molecules, and thus extends such an accelerated technique for producing the oxygen evolution reaction and electrochemical reduction of CO2 to CO.

Hemin-loaded narrow-walled mesoporous silica nanoparticles (hemin-NMSNs) as movable nanoparticles models were guided into the cells for the removal of intracellular ROS. These autonomous motions with random direction greatly enhanced the efficiency of ROS removal at low doses and alleviates safety concerns related to the potential toxicity of high doses of hemin.

Bacterial infectious diseases, such as sepsis, can lead to impaired function in the lungs, kidneys, and other vital organs. Although established technologies have been designed for the extracorporeal removal of bacteria, a high flow velocity of the true bloodstream might result in low capture efficiency and prevent the realization of their full clinical potential. Here, we develop a dialyzer made by three-dimensional carbon foam pre-grafted with nanowires to isolate bacteria from unprocessed blood. The tip region of polycrystalline nanowires is bent readily to form three-dimensional nanoclaws when dragged by the molecular force of ligand-receptor, because of a decreasing Young’s moduli from the bottom to the tip. The bacterial capture efficiency was improved from ~10% on carbon foam and ~40% on unbendable single-crystalline nanowires/carbon foam to 97% on bendable polycrystalline nanowires/carbon foam in a fluid bloodstream of 10 cm s−1 velocity.