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Encapsulating micron-sized porous silicon monoxide (SiO) with conductive carbon materials has shown enormous potential as practical high-performance anodes for lithium-ion batteries. However, constructing an ideal integral interfacial coating layer to accommodate the dynamic evolution of SiO microparticles remains a huge challenge. Here, the stress fields of SiO microparticles with three types of coating strategies are studied via finite element modeling. The results demonstrate that the soft coating can better alleviate the tensile stress during lithiation processes compared with other hard and hard–soft dual-layer coatings. Consequently, a robust SiO-based anode is intelligently designed, in which porous SiO microparticles are encapsulated in a graphene hydrogel monolith (p-SiO@rGO). The ductility and sliding characteristics of the highly interlinked graphene architecture effectively release the large tensile stress of SiO particles upon lithiation, ensuring the structural integrality of the entire electrode. The p-SiO@rGO electrode shows a superior lithium storage capacity, including high initial coulombic efficiency (76.4%), long cycling durability (589.7 mA h g−1 at 2 A g−1, 1000 cycles later) and prominent rate performance (841.6 mA h g−1 at 5 A g−1). This study provides a helpful guideline for designing high-performance SiO-based anodes with long durability for practical energy storage. [ABSTRACT FROM AUTHOR]

Facile and scalable synthesis of two-dimensional (2D) non-layered materials is highly desirable for novel applications. Iron compounds including hematite (α-Fe2O3) and iron phosphide (FeP) are an important group of semiconductors but their 2D ultrathin morphology has been rarely reported. Here, we develop a water dissolvable template-based synthesis route to produce free-standing ultrathin iron compounds. Such a method also enables the tunability of morphology from mesoporous nanosheet to meso-macroporous hierarchical nanonet utilizing the aging process, while its corresponding surface active area is reduced simultaneously. Ultrathin hematite is relatively inert to electrochemical hydrogen evolution reaction (HER). However, FeP exhibits excellent catalytic performances with a relatively low overpotential of 117 mV and a Tafel slope of 56 mV dec−1, which is as a whole improved over those of reported free-standing binary transition-metal phosphide nanostructures. This work extends the possibility to produce high-quality 2D non-layered materials, which are expected to exhibit unique properties compared to their bulk counterparts. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) layered metal dichalcogenides (LMDs) with semiconducting character have been attracting increasing attention in both fundamental studies and various applications. In the case of electrode material design for energy storage, integrating metal dichalcogenides with other conductive phases such as nanocarbons has been widely recognised as an efficient way to simultaneously achieve good electrochemical activity and conductivity. However, controllable growth of metal dichalcogenides on nanocarbons with well-defined structure and efficient interfacial contact is still highly challenging. In this work, we report a new class of SnS2 nanosheets with distinct growth orientations on the surfaces of reduced graphene oxide (RGO) and carbon nanotubes (CNTs). We further demonstrate a spatial confinement strategy to in situ grow SnS2 nanoparticles, which are homogeneously confined within RGO or CNT based porous carbon matrices. Consequently, these resultant 3D architectures demonstrate outstanding rate capability and cycling stability due to their synergistic effect of electrochemically active SnS2 particles and highly conductive carbon matrixes. In particular, the free-standing CNT sponge based composite delivers specific capacities of 741 and 462 mA h g−1 at 3200 mA g−1 for Li+ and Na+ storage, respectively, among the best values reported for both lithium ion battery (LIB) and sodium ion battery (NIB) systems. This work not only provides better understanding of the growth mechanisms of metal dichalcogenides on nanocarbons but also opens a new way to construct unique 2D heterostructures for various applications. [ABSTRACT FROM AUTHOR]

A series of dendritic mesoporous silica–titania nanospheres (DMSTN) with tunable Ti/Si molar ratios (φ = 0, 0.04, 0.13, and 0.4) has been successfully prepared through a post-treatment method. These materials possess high surface areas (450–550 m2 g−1), large pore volumes (0.9–1.04 cm3 g−1) and radially oriented mesopores (9.35–10.35 nm). The photodegradation of methylene green (an organic dye) was tested using DMSTN and a commercial photocatalyst (TiO2 Degussa P25) for comparative purposes. DMSTN exhibit excellent photocatalytic performance including higher adsorption capacity and better photocatalytic degradation performance compared to P25. [ABSTRACT FROM AUTHOR]

Small molecular weight proteins (5.21 kDa) were used as bio-templates to synthesize MnO2 nanosheets (NSs). This work will open up a protein-directed avenue to synthesize 2D morphology. Further, the as-prepared MnO2 NSs showed intrinsic peroxidase-like activity and were then applied for glucose detection and evaluation of antioxidant behaviours of typical antioxidants. [ABSTRACT FROM AUTHOR]

A novel solution approach is reported for the fabrication of TiO2 nanotube arrays on transparent conductive substrates via in situ conversion from nanowires. The as-prepared nanotube arrays not only demonstrate a larger surface area in comparison with the primary NWs, but also longer charge carrier lifetime than that of randomly packed nanoparticle films. [ABSTRACT FROM AUTHOR]

In this work, a novel type of hollow mesoporous silica nanoparticle (HMSN) with a rough surface has been successfully prepared via a facile soft–hard template route by using a carbon nanosphere as a hard template and cetyltrimethylammonium bromide (CTAB) as a soft template, respectively. This method involves the preparation of a carbon nanosphere, sequential coating of double SiO2 layers, and the removal of the inner carbon core and CTAB to produce HMSNs. The obtained HMSNs possess spherical morphology, a mesoporous shell, and crumpled surfaces. The controlled experiments prove that the addition of 3-ammonia propyl triethoxy silane (APTES) is very crucial for the formation of desired HMSNs. The cell tests indicate that HMSNs show a good biocompatibility. As a result, the potential applications of HMSNs are further explored for drug delivery and protein adsorption, using doxorubicin hydrochloride (DOX) and Cytochrome c (Cyt c) as the model drug and protein, respectively. The HMSNs exhibit high drug loading and protein adsorption capacity, as well as the controlled pH-responsive release behavior for DOX. Therefore, the HMSNs prepared are ideal candidates for various applications such as nanoreactors, drug delivery and protein adsorption. [ABSTRACT FROM AUTHOR]

Chrysanthemum-like mesoporous silica nanoparticles (MSNs) with large surface areas were successfully synthesized in the presence of ethyl ether by a facile two-step method under mild conditions. Pyrene was chosen to evaluate their drug loading and controlled release properties. The results showed that prepared MSNs exhibited excellent release rate. [ABSTRACT FROM AUTHOR]

Small molecular weight proteins (5.21 kDa) were used as bio-templates to synthesize MnO 2 nanosheets (NSs). This work will open up a protein-directed avenue to synthesize 2D morphology. Further, the as-prepared MnO 2 NSs showed intrinsic peroxidase-like activity and were then applied for glucose detection and evaluation of antioxidant behaviours of typical antioxidants.

A novel solution approach is reported for the fabrication of TiO₂ nanotube arrays on transparent conductive substrates via in situ conversion from nanowires. The as-prepared nanotube arrays not only demonstrate a larger surface area in comparison with the primary NWs, but also longer charge carrier lifetime than that of randomly packed nanoparticle films.