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AuPd nanoparticles with ultrafine sizes and good dispersion are successfully anchored on amine-functionalized monochlorotriazinyl β-cyclodextrin, and exhibit remarkable catalytic activity for hydrogen evolution from formic acid, affording an unprecedented initial turnover frequency of 7352 mol H2 per mol catalyst h−1 without any additives.

The design and synthesis of an efficient adsorbent for antibiotics-based pollutants is challenging due to the unique physicochemical properties of antibiotics. The development of a mesoporous SiO2–ZnO composite is a novel way to achieve excellent adsorption efficiency for doxycycline hydrochloride (DOX) in aqueous solutions due to the engineered highly open mesoporous structure and the ZnO-modified framework. Unlike the traditional method of obtaining mesoporous composites by post-synthesis techniques, the novel one-step method developed in this study is both effective and environment-friendly. The adsorption mechanism based on the novel synergetic effect between SiO2 and ZnO was demonstrated through several experiments. SiO2 led to the creation of a 3D open framework structure that provides sufficient space and rapid transport channels for adsorption, ensuring rapid adsorption kinetics. A higher number of active sites and enhanced affinity of the contaminants are provided by ZnO, ensuring high adsorption capacity. The mesoporous SiO2–ZnO could be easily regenerated without a significant decrease in its adsorption efficiency. These results indicate that the developed strategy afforded a simple approach for synthesizing the novel mesoporous composites, and that mesoporous SiO2–ZnO is a possible alternative adsorbent for the removal of DOX from wastewater.

The excessive use of antibiotics has led to various environmental problems; the control and separation of these antibiotics are important in environmental science. Herein, a novel mesoporous nanocomposite, Fe3O4@SiO2@mSiO2-CD, has been synthesized for the removal of antibiotic compounds from aqueous media. The well-designed nanocomposite is composed of β-cyclodextrin functionalized surfaces, ordered mesoporous silica shells with large radially oriented mesopores, and nonporous silica-coated magnetic cores (Fe3O4). The synergistic action of both the mesoporous structure and the accessible cavity of β-cyclodextrin ensures the good adsorption of doxycycline. Furthermore, the Fe3O4@SiO2@mSiO2-CD nanocomposite can be collected, separated and easily recycled from aqueous solution using an external magnet.

In this work, we report the fabrication of novel multifunctional microspheres which are composed of ordered mesoporous silica shells with accessible carboxyl functionalized surfaces and radially oriented large mesopores, and nonporous silica-coated magnetite cores (Fe3O4), aiming to remove heavy metal ions from aqueous media. The well-designed multifunctional microspheres were thoroughly characterized with transmission electron microscopy, scanning electron microscopy, infrared spectroscopy, N2 adsorption–desorption, X-ray diffraction as well as magnetization measurements. The as-prepared microspheres possess unique properties including stably grafted and accessible carboxyl groups, highly open mesopores (11.03 nm), high magnetization (34.5 emu g−1), and large BET surface areas (165 m2 g−1), and as a result, the as-prepared microspheres exhibit an enhanced performance for the removal of Cd(II), Cu(II), and Pb(II) from wastewater, with a high adsorption capacity, a rapid adsorption rate, and an easy magnetically separable process.

AgAuPd nanoparticles with small particle size, good dispersity and high degree of crystallinity on graphene are synthesized by a facile co-reduction route. The resultant AgAuPd/graphene exhibits 100% H2 selectivity, 100% conversion and excellent catalytic activity toward the hydrogen generation from decomposition of formic acid without any additive at room temperature.

Noble-metal-free NiFeMo nanoparticles without any surfactant or support have been facilely synthesized and successfully applied as a highly efficient catalyst for the rapid and complete decomposition of hydrous hydrazine (a promising hydrogen storage/generation material) for hydrogen generation at a mild temperature. The surfactant/support-free nanoparticles possess good dispersion and small particle size. Moreover, upon the incorporation of Mo and Fe, the catalytic activity and hydrogen selectivity of the present trimetallic catalyst are remarkably improved compared with its mono-/bi-metallic counterparts.

AuPd-CeO2 nanocomposites directly nucleated and grown on nitrogen-doped reduced graphene oxide, exhibit excellent catalytic activity and 100% hydrogen selectivity toward formic acid decomposition for hydrogen generation without any additives at room temperature.

Ultrafine and well dispersed CoAuPd nanoparticles grown on a DNA-reduced-graphene-oxide (DNA-rGO) composite have been successfully synthesized using a DNA-directed method. The resultant CoAuPd/DNA-rGO composite exhibits high activity and 100% H2 selectivity toward the dehydrogenation of formic acid without any additive at 298 K.

Here we report a green and facile strategy for the direct nucleation and growth of ultrafine (1.8 nm) and well dispersed Au@Pd core–shell nanoclusters on nitrogen-doped mildly reduced graphene oxide (Au@Pd/N–mrGO) without any surfactant and additional reducing agent. During the synthesis, N–mrGO acts as both the reducing agent and support by taking advantage of its moderate reducing and high dispersing capacities. Unexpectedly, the as-prepared Au@Pd/N–mrGO hybrid exhibits much greater activity than its alloy or monometallic counterparts toward hydrogen generation from formic acid aqueous solution without using any additive at room temperature.

Ag0.1Pd0.9 nanoparticles assembled on reduced graphene oxide are synthesized by a facile co-reduction route. The resultant AgPd nanoparticles/reduced graphene oxide exert 100% H2 selectivity and exceedingly high activity toward the complete decomposition of formic acid at room temperature under ambient conditions.

Amorphous Ni0.9Pt0.1/Ce2O3 nanoparticles with low noble-metal content have been facilely synthesized by a co-reduction route within 10 min at room temperature under ambient atmosphere. The resultant Ni0.9Pt0.1/Ce2O3 nanoparticles were successfully applied as a highly efficient catalyst for rapid and complete conversion of hydrous hydrazine. A high initial turnover frequency value of 28.1 h−1 for Ni0.9Pt0.1/Ce2O3 nanoparticles is achieved with 100% H2 selectivity at 298 K. Moreover, the amorphous Ni0.9Pt0.1/Ce2O3 catalyst obtained due to the addition of Ce2O3 demonstrates much better activity and much lower activation energy than that of the crystalline Ni0.9Pt0.1. The development of the improved performance and low-cost catalyst is a promising step towards the application of hydrous hydrazine as a hydrogen storage material.

A general and energy-efficient strategy has been successfully applied for synthesis of a graphene–CuCo nanohybrid, which leads to the highest catalytic activity of Cu-based catalysts up to now toward the dehydrogenation of ammonia borane, and also the excellent activity for electrochemical hydrogen evolution reaction. Moreover, this general method can be easily extended to facile preparation of other graphene–metal systems.