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The optimization of structure and composition is essential to improve the performance of catalysts. Herein, mesoporous nanoparticles assembled PdNi/Ni nanotubes (mPdNi/Ni NTs) are successfully fabricated using nickel nanowires as sacrificial template. The combination of nanotubular structure with mesoporous nanoparticle morphology can provide facilitated transfer channels and sufficient active sites, allowing the full contact and reaction between catalysts and reactants. Therefore, the synthesized mPdNi/Ni NTs exhibite superior ethanol oxidation performance to mesoporous Pd nanotubes and commercial Pd black. This study proposes a rational strategy for the development of nanoparticle assembled nanotubes with surface mesoporous morphology, which can greatly improve catalytic performance in various electrocatalytic fields.

The realization of water electrolysis on the basis of highly active, cost-effective electrocatalysts is significant yet challenging for achieving sustainable hydrogen production from water. Herein, N-doped Ni3 S2 /N-doped MoS2 1D hetero-nanowires supported by Ni foam (N-Ni3 S2 /N-MoS2 /NF) are readily synthesized through a chemical transformation strategy by using NiMoO4 nanowire array growth on Ni foam (NiMoO4 /NF) as the starting material. With the in situ generation of Ni3 S2 /MoS2 heterointerfaces within nanowires and the incorporation of N- anions, an extraordinary hydrophilic nature with abundant, well-exposed active sites and optimal reaction dynamics for both oxidation and reduction of water are obtained. Attributed to these properties, as-converted N-Ni3 S2 /N-MoS2 /NF exhibits highly efficient electrocatalytic activities for both hydrogen and oxygen evolution reactions under alkaline conditions. The superior bifunctional properties of N-Ni3 S2 /N-MoS2 /NF enable it to effectively catalyze the overall water-splitting reaction.

Designing and constructing nano-architectures with abundant reactive atoms exposed on the surface and widely open pore interiors is an effective strategy for highly efficient utilization of Pt-based catalysts. Herein, we report a facile method to synthesize tri-metallic PtPdIr mesoporous hollow nanospheres (PtPdIr MHNSs) by selective chemical removal of sacrificial metallic cores from pre-constructed Pd@PtIr mesoporous nanospheres (Pd@PtIr MNSs). The unique nano-architectures, with mesoporous shells interconnected into the interior hollow cavities and the synergistic electronic effect from tri-metallic PtPdIr composition, enable the as-synthesized PtPdIr MHNSs to be efficient bifunctional electrocatalysts for catalyzing both methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR).

High surface area and fast mass transport rate are important to enhance the activity and stability of catalysts. In this work, tellurium nanowires and F127 triblock copolymer are used as self-sacrificial and soft templates, respectively, to synthesize PtRuTe mesoporous nanotubes (MNTs). The designed PtRuTe MNTs show uniformly distributed mesopores and an internally hollow structure, which can effectively improve Pt utilization, the catalytic activity and durability, and CO tolerance for the methanol oxidation reaction. Very different from previous 1D metallic catalysts with solid interiors and smooth surfaces, PtRuTe MNTs are unique, with a mesoporous exterior and hollow interior. The facile route presented herein is very feasible for fabricating 1D mesoporous metallic catalysts.

Tailoring metal oxide nanostructures with mesoporous architectures is vital to improve their electrocatalytic performance. Herein, we demonstrate the synthesis of 2D mesoporous Co3 O4 (meso-Co3 O4 ) nanobundles with uniform shape and size by employing a hard-template method. In this study, the incipient wetness impregnation technique has been chosen for loading metal precursor into the silica hard template (SBA-15). The results reveal that the concentration of a saturated precursor solution plays a vital role in mesostructured ordering, as well as the size and shape of the final meso-Co3 O4 product. The optimized precursor concentration allows us to synthesize ordered meso-Co3 O4 with four to seven nanowires in each particle. The meso-Co3 O4 structure exhibits excellent electrocatalytic activity for both glucose and water oxidation reactions.

Tailoring of new hydrogen evolution reaction (HER) electrocatalyst with earth abundant elements is important for large scale water splitting and hydrogen production. In this work, we present a simple synthetic method for incorporating iron phosphide (FeP) particles into three-dimensional (3D) porous graphene aerogel (GA) structure. The FeP formed in porous 3D GA (FeP/GA) is derived from electroactive Fe hexacyanoferrate (FeHCF). The advantage of incorporating FeP, in the porous 3D graphene network enables high accessibility for HER. As synthesized FeP/GA catalyst shows good electrocatalytic activity for HER in both acidic and alkaline solutions. The developed method can be useful for synthesizing metal hexacyanoferrate derived mono/bimetal phosphide catalyst in porous 3D graphene aerogels.

Because n-butanol as a fuel additive has more advantageous physicochemical properties than those of ethanol, ethanol valorization to n-butanol through homo- or heterogeneous catalysis has received much attention in recent decades in both scientific and industrial fields. Recent progress in catalyst development for upgrading ethanol to n-butanol, which involves homogeneous catalysts, such as iridium and ruthenium complexes, and heterogeneous catalysts, including metal oxides, hydroxyapatite (HAP), and, in particular, supported metal catalysts, is reviewed herein. The structure-activity relationships of catalysts and underlying reaction mechanisms are critically examined, and future research directions on the design and improvement of catalysts are also proposed.

To develop low-cost and efficient oxygen reduction reaction (ORR) catalysts, a novel hybrid comprising cobalt-embedded nitrogen-doped carbon nanotubes and nitrogen-doped reduced graphene oxide (Co-NCNT/NrGO-800) was simply prepared by pyrolysis. The combination of nanotubes and graphene, and the efficient doping with cobalt and nitrogen, greatly contribute to the excellent ORR performance. This optimized Co-NCNT/NrGO catalyst exhibits a positive onset potential of 0.91 V and a half-wave potential of 0.82 V, combined with a relatively low peroxide yield, better durability, and better methanol tolerance than commercially available Pt/C, which makes it a promising candidate as a low-cost and effective non-precious-metal ORR catalyst.

Engineering the size, composition, and morphology of platinum-based nanomaterials can provide a great opportunity to improve the utilization efficiency of electrocatalysts and reinforce their electrochemical performances. Herein, three-dimensional platinum-palladium hollow nanospheres with a dendritic shell (PtPd-HNSs) are successfully fabricated through a facile and economic route, during which SiO2 microspheres act as the hard template for the globular cavity, whereas the triblock copolymer F127 contributes to the formation of the dendritic shell. In contrast with platinum hollow nanospheres (Pt-HNSs) and commercial platinum on carbon (Pt/C) catalyst, the novel architecture shows a remarkable activity and durability toward the methanol oxidation reaction (MOR) owing to the coupled merits of bimetallic nanodendrites and a hollow interior. As a proof of concept, this strategy is also extended to trimetallic gold-palladium-platinum hollow nanospheres (AuPdPt-HNSs), which paves the way towards the controlled synthesis of other bi- or multimetallic platinum-based hollow electrocatalysts.

Certain bimetallic nanocrystals (NCs) possess promising catalytic properties for electrochemical energy conversion. Herein, we report a facile method for the one-step synthesis of porous dendritic PtNi NCs in aqueous solution at room temperature that contrasts with the traditional multistep thermal decomposition approach. The dendritic PtNi NCs assembled by interconnected arms are efficient catalysts for the oxygen reduction reaction. This direct and efficient method is favorable for the up-scaled synthesis of active catalysts used in electrochemical applications.

The field of mesoporous metal nanoarchitectonics offers several advantages which cannot be found elsewhere. These materials have been showcasing impressive enhancements of their electrochemical properties for further implementation, compared to their micro- and macroporous counterparts. Since the last few decades, various methods have been developed to achieve narrow pore size distribution with a tunable porosity and particle morphology. While hard templates offer a reliable and intuitive approach to synthesize mesoporous metals, the complexity of the technique and the use of harmful chemicals pushed several research groups to focus in other directions. For example, soft templates (e.g., lyotropic crystals, micelles assemblies) and solution phase methods (requiring to control reduction reactions) offer more and more possibilities in terms of available compositions and morphologies. Indeed, various metal (Pt, Pd, Au, Ru, etc.) can now be synthesized as dendritic, core@shell, hollow or polyhedral nanoparticles, with single- or multicomponents, alloyed or not, with unprecedented electrochemical activity.

Film star: The synthesis of mesoporous Pt-Au alloy films of varying composition by using a square-wave potential program is described. A Pt(51)Au(49) alloy film exhibits superior performance for the detection of glucose than those reported previously. The activity was found to be strongly dependent on the synergistic effects of the mesoporous structure and the Pt-Au alloy surface.

The field of mesoporous metal nanoarchitectonics offers several advantages which cannot be found elsewhere. These materials have been showcasing impressive enhancements of their electrochemical properties for further implementation, compared to their micro- and macroporous counterparts. Since the last few decades, various methods have been developed to achieve narrow pore size distribution with a tunable porosity and particle morphology. While hard templates offer a reliable and intuitive approach to synthesize mesoporous metals, the complexity of the technique and the use of harmful chemicals pushed several research groups to focus in other directions. For example, soft templates (e.g., lyotropic crystals, micelles assemblies) and solution phase methods (requiring to control reduction reactions) offer more and more possibilities in terms of available compositions and morphologies. Indeed, various metal (Pt, Pd, Au, Ru, etc.) can now be synthesized as dendritic, core@shell, hollow or polyhedral nanoparticles, with single- or multicomponents, alloyed or not, with unprecedented electrochemical activity.

The aim of the current study was to explore the effect of health-related behaviours and the support of family members on the clinical symptoms of benign prostatic hyperplasia (BPH) patients, and to provide some clues for the symptoms control of BPH. The data were collected in three hospitals in Hubei Province, China, from June to September 2011. The health-related behaviours included cigarette smoking, alcohol intake, tea and coffee consumption, and drinking water regularly, and the support of family members included the support from spouse, siblings, and offspring in the previous year. The χ2 test and multivariable logistic regression models were used to assess their effects on the International Prostatic Symptom Score (IPSS). With regard to health-related behaviours, only coffee consumption (OR = 0·33, 95% CI: 0·11–0·96) and drinking water regularly (OR = 0·44, 95% CI: 0·24–0·81) had significant effects on the IPSS. Although the χ2 test suggested that support from offspring of patients with BPH was statistically significant, after adjusting for potential confounding variables the association was not statistically significant. Although there were some limitations, the current study provides preliminary clues and evidences for the role of coffee intake and regularly drinking water played in the Chinese men with BPH. More in-depth research is needed to enhance the role of health-related behaviours and social factors in the clinical practice of BPH.

Mesoporous Pt-Ru alloy films with various compositions were synthesized by electrochemical plating in an aqueous surfactant solution. After the removal of surfactants, continuous mesoporous Pt-Ru alloy films possessing uniform mesopores with diameter about 7 nm were obtained. The Ru content in the films could be controlled from 0 to 13 at % by changing the precursor compositions. For all the films, the mesostructural periodicities and the mesopore sizes in the films were not changed. Due to the mesoporous structure and the doped Ru content, our mesoporous Pt-Ru films showed superior electrocatalytic activity for methanol oxidation reaction in comparison with the commercially available Pt catalyst.

Chemical Equation Presentation On display: A high-speed and high-quality passive-matrix electrochromic display (ECD) is constructed from a leuco dye and a TiO nanoporous electrode (see picture). The vertical pores prevent the drifting of the colored dye molecules, leading to a clear image at high driving speeds. With full-color features, this kind of ECD promises to be a competitive candidate for a reflective electric display.

In par-ticular, two-dimensional (2D) hexagonal mesoporous filmshave been widely prepared with different types of surfac-tants by various methods. Fine controls of 1D mesochannelsin a certain direction are required in order to employ thesematerials as the recording media, nanofluidic, optoelectronicdevices, and fabrication of the oriented nanowires. Thus,several efforts have been proposed to control the mesochan-nel orientation in mesoporous films.As well-known alignment strategies, external fields suchas electric