Hybridizing nanostructured metal oxides with multiwalled carbon nanotubes (MWCNTs) is highly desirable for the improvement of electrochemical performance of lithium-ion batteries. Here, a facile and scalable strategy to fabricate hierarchical porous MWCNTs/Co3O4 nanocomposites has been reported, with the help of a morphology-maintained annealing treatment of carbon nanotubes inserted metal organic frameworks (MOFs). The designed MWCNTs/Co3O4 integrates the high theoretical capacity of Co3O4 and excellent conductivity as well as strong mechanical/chemical stability of MWCNTs. When tested as anode materials for lithium-ion batteries, the nanocomposite displays a high reversible capacity of 813 mAh g(-1) at a current density of 100 mA g(-1) after 100 charge-discharge cycles. Even at 1000 mA g(-1), a stable capacity as high as 514 mAh g(-1) could be maintained. The improved reversible capacity, excellent cycling stability, and good rate capability of MWCNTs/Co3O4 can be attributed to the hierarchical porous structure and the synergistic effect between Co3O4 and MWCNTs. Furthermore, owing to this versatile strategy, binary metal oxides MWCNTs/ZnCo2O4 could also be synthesized as promising anode materials for advanced lithium-ion batteries.

Oxygen evolution: A 3D nickel foam/porous carbon/anodized nickel electrode was designed for the oxygen evolution reaction (see picture). The conductive porous carbon membrane, which is derived from a zeolite imidazolate framework, plays a key role as an interlayer to both protect the inner instable Ni foam and support the outermost oxygen‐evolving Ni catalyst layer.

Developing probes for the detection of reactive oxygen species (ROS), a hallmark of many pathophysiological process, is imperative to both understanding the precise roles of ROS in many life-threatening diseases and optimizing therapeutic interventions. We herein report an all-in-one fluorescent semiconducting polymer based far-red to near-infrared (NIR) Pdot nanoprobe for the ratiometric detection of hypochlorous acid (HOCl). The fabrication takes the advantage of flexible polymer design by incorporating target-sensitive and target-inert fluorophores into a single conjugated polymer to avoid leakage or differential photobleaching problems existed in other nanoprobes. The obtained nanoprobe has improved performance in HOCl sensing, such as high brightness, ideal far-red to NIR optical window, excellent photostability, self-referenced ratiometric response, fast response, and high selectivity. The dual-emission property allows the sensitive imaging of HOCl fluctuations produced in living macrophage cells and peritonitis of living mice with high contrast. This study not only provides a powerful and promising nanoprobe to be potentially used in the investigations of in situ HOCl status of diseases in living systems but also puts forward the design strategy of a new category of ratiometric fluorescent probes facilitating precise and reliable measurement in biological systems.

The synthesis of high-efficiency and low-cost catalysts for hydrodeoxygenation (HDO) of waste lignin to advanced biofuels is crucial for enhancing current biorefinery processes. Inexpensive transition metals, including Fe, Ni, Cu, and Zn, were severally co-loaded with Ru on HY zeolite to form bimetallic and bifunctional catalysts. These catalysts were subsequently tested for HDO conversion of softwood lignin and several lignin model compounds. Results indicated that the inexpensive earth-abundant metals could modulate the hydrogenolysis activity of Ru and decrease the yield of low-molecular-weight gaseous products. Among these catalysts, Ru-Cu/HY showed the best HDO performance, affording the highest selectivity to hydrocarbon products. The improved catalytic performance of Ru-Cu/HY was probably a result of the following three factors: (1) high total and strong acid sites, (2) good dispersion of metal species and limited segregation, and (3) high adsorption capacity for polar fractions, including hydroxyl groups and ether bonds. Moreover, all bifunctional catalysts proved to be superior over the combination catalysts of Ru/Al O and HY zeolite.

Graphene supported Pd@Co core-shell nanocatalysts with magnetically recyclability were synthesized via the in situ synthesis strategy utilizing the distinction in reduction potentials of the two precursors with appropriate reductant. The as-synthesized catalysts exerted satisfied catalytic activity (916 L mol À1 min À1 ) and recycle stability for hydrolytic dehydrogenation of ammonia borane.Hydrogen, as an ideal alternative to petrochemical energy, has attracted widespread research concerns and interests. 1 Among many significant barriers toward establishing hydrogen as a viable resource, exploring efficient hydrogen storage materials remains a daunting challenge. 2 Currently chemical hydrides have attracted a great deal of attention because of their high gravimetric and volumetric storage capacity. 3 Among them, ammonia borane (NH 3 BH 3 , AB) has the advantages of the high hydrogen content (19.6 wt%) and high stability under the ambient conditions, which make it one of the most compelling candidates for chemical hydrogen storage applications. 4 Therefore, development of efficient, economical and stable catalysts is highly desired to further improve the kinetic properties under moderate conditions for the practical application of this system. 5 To date, not only noble and non-noble metal-based catalysts but also their composites have shown the high efficacy to catalyze the hydrolytic dehydrogenation of AB. 6 Investigations of these catalysts have revealed that the catalytic performance is highly dependant on the dispersion of the active metals. 7 To solve this problem, many techniques have been designed for restraining the agglomeration of nanocatalysts, such as, stabilizing nanoparticles (NPs) with surfactants, coating NPs with inert shells, and contriving the microreactors. 8 Graphene, as an exciting material, has many merits of large theoretical specific surface area, high intrinsic mobility, high thermal and electrical conductivity, and thus is applied in fields such as physics, chemistry as well as materials science. 9 Hence, it is understandable to use graphene as the substrate to anchor NPs with good dispersion. In addition, the rational structure designs of nanocatalysts have also been convinced to enhance the catalytic activity. 10 Accordingly, the cooperative effect can be expected between graphene and nanostructures to facilitate the reaction.Herein, we report the in situ synthesis of magnetically recyclable graphene-supported Pd@Co core-shell NPs (Pd@Co/graphene) utilizing the distinction in reduction potentials of the two precursors with AB as the reducing agent at ambient conditions. Interestingly, compared with its alloyed (PdCo/graphene) and graphene-free (Pd@Co) counterparts, the as-synthesized nanocatalysts exert the most excellent catalytic activity and recycle stability toward the hydrolytic dehydrogenation of AB at ambient conditions. Briefly, the in situ synthetic and catalytic procedure was achieved by adding AB into the precursor solution containing Na 2 PdCl 4 , Co(NO 3 ) 2 , and graphen...

Formic acid (FA) holds great potential as a convenient source of hydrogen for sustainable chemical synthesis and renewable energy storage. Herein, the non-noble metal nickel (Ni) exhibits superior promoting effect in improving the catalytic activity of Pd toward high activity and selectivity for FA decomposition at room temperature.

Visualizing the progression of fatty liver disease in vivo is of great significance in biomedical research of fatty liver, but hindered by the lack of suitable approaches with deep penetration, high specificity, and real-time observability for fatty liver imaging. Herein, two bright NIR-I/NIR-II fluorophores with D-π-A-π-D structures are designed and synthesized for fatty liver tracking in vivo. Such fluorophores show an ultrahigh quantum yield of 49.2% and 17.3% at the emission maximum of 930 and 975 nm, respectively. Most interestingly, these two fluorophores display ultrasensitive fluorescence response (over 100-fold enhancement) toward the variations of environment polarity. Accordingly, further doping of these fluorophores into amphiphilic organic matrix allows the formation of ultrabright NIR-I/NIR-II fluorescent nanoprobes for high-resolution fluorescence imaging of the vessels. Additionally, with the assistance of such nanoprobes and NIR-II fluorescence imaging, real-time monitoring of heartbeat rate and the respiratory rate, accurate identification, and imaging-guided surgery of the submillimeter scale lymph nodes are successfully realized. Moreover, the as-designed fluorophores show superior performance for indicating lipid droplets (LDs) in living cells. Ultimately, precise monitoring of fatty liver with NIR-I/NIR-II fluorescent LDs probe is first confirmed, demonstrating the possibility for staging fatty liver disease with a contact-free method.

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