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[Display omitted] • The pore microstructure and surface-interface coupled to mediate the morphology-performance relationship. • Quantitatively analyzed the driven effect of the pore size and micromorphology on EDL progress. • Elucidated the ions storage behaviors mediated by surface-interface characteristics. • Electrodes with high-energy crystal facets and 3D porous structure performed good cycling stability. Manganese dioxide (MnO 2) materials are one of promising cathode candidates for capacitive deionization (CDI) applications, with their morphology significantly impacting the performance of the electrode material itself. Therefore, this study systematically investigates the structure-performance relationships and the micro-interface ion storage mechanisms of four morphologies of MnO 2 (1D nanorods (NNMO), nanowires (NWMO), 3D microspheres (MMO), and hollow urchin-like spheres (HUMO)) in relation to their capacitive deionization performance with typical heavy metal ions (Cd2+) through experimental and theoretical calculations. In terms of pore morphology, capacitance significantly increases with increasing surface curvature of materials, demonstrating a clear pore structure-dependent characteristic. NNMO, with the smallest pore size, has much lower surface capacitance (∼0.15 μF cm−2) than other materials (∼0.33 μF cm−2). As pore size increases, the capacitance distribution difference driven by pore structure size gradually disappears. Regarding surface and interface characteristics, high-energy crystal facets facilitate electron transfer ({310}>{200}≈{211}>{100}) and increase the proportion of surface active sites (O sur), thus promoting CDI absorption kinetics. During the capacitive deionization process, the pore structure (∼77 %) and surface-interface characteristics (∼23 %) exhibit highly coupled features and the driving force for interfacial ion storage among the four materials is in the order of HUMO>MMO>NWMO>NNMO. This work elucidates the morphology-dependent capacitive processes of MnO 2 nanomaterials, enhancing the understanding of structure- electrochemical process at the nanoscale but also providing effective guidance for the design and development of practical, high-performance CDI electrode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Uniform and monodispersed Au@CuS/Ni-CoS 2 /C nanocages were prepared. • Novel donor–acceptor pairs of Au and CuS boost NRR catalytic activity. • Electron-rich Au sites facilitate N 2 adsorption and subsequent reduction. • Optimal hollow structure maximizes Au@CuS active site exposure. • Impressive NH 3 yield and Faraday efficiency were achieved. The nitrogen reduction reaction (NRR) offers a sustainable pathway for ammonia production. However, its effectiveness is hindered by the selective adsorption of nitrogen and the subsequent occurrence of the hydrogen evolution reaction. In this work, a novel and efficient NRR catalyst, Au@CuS heterostructured nanoparticles supported on carbon-coated Ni-doped CoS 2 hollow nanocages (Au@CuS/Ni-CoS 2 /C), was designed and synthesized to enhance the conversion of N 2 to NH 3 under ambient conditions. The defective Ni-CoS 2 @C nanocages not only provide a larger surface area for the loading of Au@CuS nanoparticles but also improve conductivity and promote synergistic effects among different components within catalyst. Both experimental investigations and density functional theory (DFT) calculations reveal that the integration of Au and CuS leads to unique inorganic donor–acceptor couplings with electron enriched in Au nanoparticles due to the higher work function of Au compared to CuS. This electron enrichment expedites the adsorption and dissociation of N 2 molecules over the electron-rich Au active sites, thereby significantly optimizing the adsorption of intermediates and catalyzing subsequent hydrogenation reduction processes. Benefiting from these synergistic advantages, the resulting Au@CuS/Ni-CoS 2 /C catalyst exhibited high NRR electrocatalytic activity with a maximum NH 3 yield of 25.61 µg h−1 mg−1 cat. and a Faraday efficiency of 14.99 % at –0.3 V (vs. reversible hydrogen electrode, RHE), surpassing those of Au@CuS, Ni-CoS 2 /C, and Au/Ni-CoS 2 /C. This work presents a new strategy for precisely adjusting the valence state of Au species, thereby facilitating the production of valuable ammonia through NRR. [ABSTRACT FROM AUTHOR]

• We develop a strategy utilizing polysilanes as bifunctional modifier for Sn perovskite solar cells. • Poly-methyl-phenyl-silane (PMPS) could enhance V oc and J sc simultaneously through defects passivation and morphology repairment. • The optimized devices achieve over 14% PCE with highly reproducibility. As a safer and more environmentally friendly alternative to lead-based perovskite, lead-free tin halide perovskite solar cells (PSCs) have gained significant attention. However, these cells have faced challenges, including poor quality from easy oxidation and fast crystallization, resulting in a rough surface morphology with numerous defects. To address these issues, we developed a strategy utilizing polysilanes, specifically polymethyl-phenyl-silane (PMPS) and deca-phenyl-penta-silane (DPPS), to enhance the quality of tin perovskite. Various modification methods, such as precursor doping, antisolvent modification, and surface passivation, were attempted. A promising 14.18 % efficiency of Tin PSC with better stability was achieved through surface passivation of PMPS. Further characterization showed that PMPS could work as a bifunctional molecule: smooth surface morphology and enlarge grain size (short-circuit current (J sc) enhancement) as well as reductant for Sn4+ and regulator of surface energy level (open-circuit voltage (V oc) enhancement). [ABSTRACT FROM AUTHOR]

Highlights • Synthesis of hierarchical ETS-10 zeolites with controllable morphology and pore. • Selected additives act as mesoporogen, morphology- and structure-directing agents. • Lignosulphonate leads to formation of an analogous molecular-recognition pattern. • Lignosulphonate-based ETS-10 catalyst shows the most remarkable performance. Abstract A detailed investigation was carried out to develop novel pore- and morphology-controllable ETS-10 zeolite. The XRD, N 2 adsorption/desorption, SEM, TEM and 29Si NMR MAS results proved that a series of hierarchical ETS-10 zeolites was successfully synthesized and more importantly, their morphologies and pore sizes can be freely confined in the desired range under the mesoporogen, morphology- and structure-directing actions of different additives. What's more, the close relationship between various additives and raw materials especially titanium source was discussed, which played an active part in morphology change and hierarchical pores formation. This can be ascribed to the special reducibility of inorganic Ti source, system liquidity and pH, and the enhanced inorganic species dissolution. Finally, the synthesized hierarchical ETS-10 materials were used as heterogeneous catalysts for different biomass-derivatives hydrogenation. Remarkably catalytic performance can be attributed to the unique TiO 6 octahedra carrying two negative charges that strengthens the interaction with active metal species, and thus improves their dispersion. Moreover, the inherent strong Lewis basicity and moderate Lewis acidity favor the oriented conversion of reactants. The controllably hierarchical structure and morphology benefit exposure of more highly dispersed active sites and prolong the catalyst life circle. Especially, an analogous molecular-recognition pattern was found by using sodium lignosulphonate, which is identified as the leading role in noticeably enhancing the catalytic activity and selectivity of the correspondingly ETS-10-based catalyst. [ABSTRACT FROM AUTHOR]

Highlights • A facile synthetic route to copper sulfide in continuous Couette-Taylor reactor. • Morphology control of copper sulfide by level of supersaturation. • Level of supersaturation could be effectively regulated by rotational speed. Abstract In this report, a Couette-Taylor (CT) reactor was applied as an effective continuous process for synthesizing copper sulfide nanoparticles. The rotational speed, mean residence time (MRT), and concentration of the feed solution were important control factors on the morphology and size control of the nanoparticles. Increasing the rotational speed from 80 rpm to 90 rpm changed the morphology of the synthesized nanoparticles from nanofibers to hexagonal nanoplates. Only Cu 7 S 4 nanofibers were obtained in the batch reactor. Through various comparative experiments, we found that MRT and the feed solution concentration affect monomer concentration in the CT reactor, thus controlling the morphology and size of the nanoparticles. [ABSTRACT FROM AUTHOR]

• Shape and size control of metal–organic frameworks, • Microfluidic synthesis system assisted by AC Electrokinetic mixing, • Controlled microfluidic synthesis platform, • Morphological regulation strategies of MOFs under mild conditions, • Customized synthesis method for functional crystal materials. Metal-organic frameworks (MOFs) have great potential for a wide range of applications given their flexible structures and pore networks. Morphology control directly affects the properties and applications of MOFs. Unfortunately, governing the desired dimension and shape of MOFs is often limited by macrosystems that require organic solvents and additives while including time-consuming treatments. Microfluidics as a practical alternative provides precise manipulation of microscale liquid, has the potential to be a superior platform for directed crystal generation. Here we reported an AC electrokinetic (EK) mixing-assisted micro-synthesis method, which allowed the actively controlled synthesis of MOFs in aqueous phase. The effects of flow rate, molar-ratio of precursors, electric field intensity, and frequency on the synthesis of zeolitic imidazolate framework-8 (ZIF-8) were investigated. Using this method, the particle size of ZIF-8 were varied, and the geometry were changed between flower-like polyhedra, cubes, spheres, and rhombic dodecahedra. Furthermore, the synthesized various ZIF-8 provide different levels of immobilization sites based on their morphological deviations. The flower-like cubic ZIF-8 had defect structures and exhibited a maximum horseradish peroxidase (HRP) loading of about 16%. The study provides a simple, green and reliable tuning strategy for breaking the single morphological form of MOFs to enhance their physicochemical properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • An simple method is reported to fabricate 3D porous Zn-Cu alloy electrodes. • The effect of Cu on the morphology and properties of alloy electrodes are revealed. • The Cu 0.3 Zn 9.7 shows excellent catalytic performance to CO comparable to Au and Ag. • The catalytic performance of Cu 0.3 Zn 9.7 is further improved in a novel electrolyte. Designing cheap and highly active electrochemical CO 2 reduction (ECO 2 R) systems are crucial for their commercial applications. Herein, we report a 3D porous Zn-Cu alloy electrode for ECO 2 R to CO. A small amount of Cu has a dramatic effect on the micro-morphology of the electrode. Furthermore, DFT calculations confirm that Zn-Cu alloying significantly reduces the formation energy barrier of *CO intermediates. The synergy between the unique 3D porous structure and the alloying effect enables the Cu 0.3 Zn 9.7 electrode to achieve up to 90.69 % Faraday efficiency (FE) for CO at −1.2 V (vs. reversible hydrogen electrode (RHE)). Furthermore, we prepare a novel non-aqueous cathode electrolyte consisting of deep eutectic solvent (DES) and propylene carbonate (PC) for ECO 2 R. The FE CO of Cu 0.3 Zn 9.7 increased to 94.89 % and the reduction potential decreased to −1 V (vs. RHE). The low cost of preparing 3D porous electrodes and the ease of synthesizing the novel non-aqueous electrolyte render this ECO 2 R system for CO promising for large-scale application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Investigated the effects of MGDA-Na 3 and GLDA-Na 4 as additives on morphological changes of CaCO 3. • Synthetized nano-sized CaCO 3 with a distinct morphology and diameter less than 50 nm. • Adsorption of chelating agents onto the edges of CaCO 3 layers. • Prospect of absorbent regeneration is evaluated. With current energy demand and increased carbon dioxide emissions, the development of CO 2 reduction technologies is imperative. One promising approach is to capture and utilize CO 2 as a feedstock in various industrial processes. One such process is through the production of nano-sized calcium carbonate which have a wide variety of industrial applications including building materials and bio-medicine. Crystallization reaction is one of the essential factors to determine the particle size and other properties of CaCO 3. Based on this background, this study proposed a novel approach to the crystallization reaction using the chelating agent's actions under various conditions in producing high-value added CaCO 3 while capturing CO 2 , simultaneously. Due to the limited biodegradability and environmental persistence of certain chelators, biodegradable chelating agents, such as L-Glutamic acid-N,N-diacetic acid tetrasodium salt (GLDA-Na 4), and DL-Alanine-N,N-diacetic acid trisodium salt (MGDA-Na 3) were used as alternatives. These are well known as a complexing agent of Ca2+ and were selected because their presence would reduce free ions, hence weakening the nucleation driving force. The proposed process involves two phases. Surrounding Ca2+ control based on chelating-systems, followed by CO 2 mineralization. This study revealed that incorporating chelating agents promoted the synthesis of nano-sized CaCO 3 with a diameter less than 50 nm. Furthermore, the system is technically feasible since the regenerated NaOH leachate may be reused for CaCO 3 synthesis and carbonation. The suggested approach shows promise as an indispensable green technology for reducing carbon emissions and synthesizing nano-sized CaCO 3 which has high demand on industries on a global basis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Brain platygyra coral-like porous carbon architectures with uniform N atom doping have been firstly fabricated. • The fabricated sensor had a low LOD of 0.13 μM and a wide linear detection range of 1.0–26000.0 μM for the detection of H 2 O 2. • Real-time monitoring of H 2 O 2 released from living cells as well as detection of H 2 O 2 in serum samples were achieved. • It provides a facile strategy to accurately control the morphology and heteroatom doping of MOF-derived carbons. The rational design for controlling the morphology and heteroatom doping of MOF-derived carbons (MCs) is one of the challenges for their electrochemical applications. In this work, brain platygyra coral-like porous carbon architectures with uniform N atom doping have been firstly fabricated by direct carbonization of schistose MIL-101-NH 2 and simple acid etching. Due to the uniquely superficial sulci and gyri distribution, hierarchical pore structures with mesopore-connected micropores, and the functionality with uniform N atom doping and oxygen-containing functional groups, the resultant porous carbon as a novel metal-free electrocatalyst afforded high performance for H 2 O 2 reduction with a low detection limit of 0.13 μM and a wide linear detection range of 1.0–26000.0 μM. Significantly, real-time monitoring of H 2 O 2 from living cells upon stimulation as well as detection of H 2 O 2 in serum samples were achieved. This work not only provides a facile strategy to accurately control the morphology and heteroatom doping of MCs, but also opens up a new avenue for the development of metal-free biosensors for H 2 O 2 real-time sensing. [ABSTRACT FROM AUTHOR]

Under assistance of ionic liquid, the Cu 2 O crystal was successfully synthesized by a simple solution-phase method with several morphologies, including octahedrals, truncated octahedrals, facet-etched octahedrals, particle-coated octahedrals and aggregated spheres. The morphology of Cu 2 O crystals can easily be modified by tuning the adding amounts of ionic liquid 1-ethyl-3-methylimidazolium bromide. A possible growth mechanism for the crystal products can be suggested based on the DFT+ D calculation and experiments. Under visible-light irradiation (λ > 420 nm), the obtained Cu 2 O samples show an outstanding performance during photodegrading methylene blue (MB) dye. The higher photocatalytic activity for MB photodegradation by the Cu 2 O facet-etched octahedrals comparing to octahedrals can be attributed to the formation of surface heterojunction between (1 0 0) and (1 1 1) facets. Therefore, the ionic liquid-assisted solution-phase syntheses would be potentially useful in the fields of catalyst production for photodegrading hazardous pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Recent advances of microwave-synthesized catalysts for air treatment are reviewed. • Fast and homogeneous microwave heating allows delicate control of catalyst properties. • Microwave-synthesized catalysts generally perform better than conventional catalysts. • Microwave irradiation is also used to activate catalytic air remediation processes. Microwave-assisted synthesis has attracted wide attention as an efficient and energy-saving synthesis strategy due to its unique heating mechanism. Environmental catalysts prepared via microwave heating process typically exhibit uniform crystal size with desired morphology, porous structure and interfacial properties, which are important for the catalytic remediation of air pollution. This review first summarizes the principles of microwave heating, followed by the characteristics of the obtained catalysts. The research progress of representative materials (e.g., supported metal catalysts, metal oxides, and porous carbon materials) in the treatment of gaseous pollutants are then categorized in detail. Meanwhile, this review compiles the recent research outputs of air pollutants remediation by environmental catalysts from the perspective of features and reaction pathways facilitated by microwave-assisted synthesis. It demonstrates that microwave-assisted heating can not only improve the synthesis efficiency and the catalytic activity but also modify the selectivity by tuning the catalyst properties. Finally, the use of microwave irradiation to activate environmental catalytic reactions is reviewed, as the application of microwaves can lead to significant improvements due to the possibility of delivering energy directly to the catalytic materials. Nevertheless, challenges remain in the development of highly active and efficient catalyst to realize its practical application. These, together with prospects on the development of environmental catalysts using microwave techniques are provided for enlightening the future of this field of research. [ABSTRACT FROM AUTHOR]

Three novel non-fullerene acceptors (NFAs) (BTP-SO-BrF, BTP-SO-1F, and BTP-SO-2F) with asymmetric chalcogen-containing branched chains but distinct ending groups have been developed for efficient green solvent processed (GSP) organic solar cells (OSCs). The champion efficiency reaches 17.6% for PM6:BTP-SO-2F-based devices, which is the highest value in the field of GSP-OSCs based on asymmetric NFAs. [Display omitted] • Novel asymmetric NFAs with green solvent processing property are developed. • Modulating molecular geometry and morphology via ending group halogenation. • A champion PCE of 17.6% for green solvent processed binary OSCs. Despite the progress made in non-fullerene acceptor (NFA) based organic solar cells (OSCs), it is quite challenging to achieve efficient green solvent processed (GSP) OSCs. Herein, we design and synthesize three asymmetric NFAs named BTP-SO-BrF , BTP-SO-1F , and BTP-SO-2F with alkoxy/alkythio branched chains on the core unit but distinct ending groups (BrF-IC, 1F-IC, and 2F-IC), respectively. The asymmetric alkoxy/alkylthio branched chains help to enhance the solubility of these NFAs and compatibility with the PM6 polymer donor in non-halogen solvents. Furthermore, the ending group modulation studies unveil that PM6: BTP-SO-2F blend film exhibits shorter intermolecular stacking distance, more favorable fiber-like phase separation, and more balanced carrier mobilities than the other two NFAs. Consequently, optimal efficiency of 17.6% is achieved in the BTP-SO-2F -based devices with an open-circuit voltage of 0.909 V, a short-circuit current density of 24.54 mA cm−2, and an excellent fill factor of 0.789, compared to those of BTP-SO-BrF (15.5%) and BTP-SO-1F -based (16.2%) devices, which is the highest value reported for GSP-OSCs based on asymmetric NFA. Our studies reveal that the halogenation of ending groups for NFAs with asymmetric branched chains is an effective strategy to tune the morphology for high-efficiency and eco-friendly GSP-OSCs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Si@WO 3 -NS heterojunction is designed and fabricated mimicking layered thylakoid. • The morphology control for C C coupling is like in the Calvin Cycle. • The enhancement of charge separation efficiency is attributed to the build-in electric field. • The carbene mechanism is proposed and verified by operando FT-IR spectra. The photoelectrocatalytic reduction of CO 2 to high value-added chemicals is considered as one of the most promising technologies for solving both environmental and energy issues of the planet. Here, p-n heterojunction nanowires Si@WO 3 -x derived from p-silicon wafer modified by tungsten trioxide with different morphologies, including nanosheets (NS), nanobulks (NB) and nanoneedles (NN), were designed and fabricated. The Si@WO 3 -NS heterojunction gives the highest apparent quantum efficiency of light (0.49 % AQE) excluding the contribution of electrons from anode (>0.4 % QE of nature plant), which is nearly 25 times than that of pure Si NW (0.02 % AQE). The selectivity of multicarbon products (C 2+) for Si@WO 3 -NS catalyst reaches 62.7 %, benefiting from the morphology simulated to the structure of thylakoid in plants. Moreover, the mechanism was proposed and confirmed by operando FT-IR experiments indicating the existence of active species COO−, HCOO−, C−O and C−C, respectively. This engineering design for Si-based material simulated plant cell can firstly produce C 2+ chemicals without assistance of copper particles known as good catalyst or co-catalyst for C−C coupling. [ABSTRACT FROM AUTHOR]

[Display omitted] • Morphology-controlled synthesis of Cu 2 O encapsulated phase change materials. • A possible morphology-controlled mechanism was proposed based on DFT calculations. • The synthesized microcapsules possessed latent heat of 82.9–148.9 J/g. • Facet-dependent visible light absorbance of the microcapsules was revealed. • The octahedral microcapsule showed photothermal conversion efficiency of 82.65%. Microencapsulated phase change materials (MPCMs) are usually limited in photothermal conversion due to their poor visible light absorbability and low thermal conductivity. Owing to a direct band gap of 2.0–2.2 eV, the semiconductor cuprous oxide (Cu 2 O) has attracted intense interest in solar energy harvest. Shape-dependent optical properties of Cu 2 O semiconductors are mainly focused on crystals enclosed by three low-index facets ({1 0 0}, {1 1 0} and {1 1 1}). Here, we successfully design and fabricate the Cu 2 O encapsulated MPCMs from cube, truncated cube, 26-hedron, and truncated octahedron to octahedron under precise control of NaOH. A possible growth mechanism to explore the correlation between selective adsorption of OH− on Cu 2 O facets and MPCMs shape evolution is suggested based on density functional theory calculations. The thermal analysis shows that the octahedral MPCMs enclosed by {1 1 1} facets possess latent heat of 148.9 J/g and photothermal conversion efficiency of 82.65 % under irradiation of visible light. Differential scanning calorimeter (DSC) profiles of the MPCMs maintain good coincidence with only a slight fluctuation of phase transition temperatures and the associated enthalpies during the 200-cyclic scans, demonstrating excellent phase change reversibility and thermal durability. Our studies unambiguously provide a strategy for tailoring the optical properties of MPCMs to greatly harvest solar energy for green building materials, anti-ice coating etc. in the future. [ABSTRACT FROM AUTHOR]

• An enhanced imide COFs cathode is designed by a "three-in-one" structure regulation strategy. • Morphology control results in COFs nanosheets with more active sites available for sodium storage. • Molecular design leads to more active sites in the COF's skeleton. • Post synthetic vulcanization of C O sites to C S bring more active surface for COF material. • The triplex structural regulation endows the S@TAPT-COFs cathode excellent SIBs performances. Covalent organic frameworks (COFs) with stable porous structure are considered as promising electrode materials for next-generation sustainable sodium-ion batteries (SIBs). However, how to enhance their surface activity and utilize more superficial active sites remains great challenge to satisfy the potential applications. Herein, a "three-in-one" structure regulation strategy including morphology control, molecular design and post-synthetic vulcanization is proposed to design an enhanced polyimide COFs cathode. Through morphology control, two-dimensional COFs nanosheets can be easily controlled due to the directing effect of the π-π interactions between rGO and the structure units of COFs, which leads to short channels to make more active sites available for sodium storage; Through molecular design, COFs with more active atoms can be acquired by simply replacing N atom with triazine ring in monomer, resulting in more active sites in the COFs skeleton; Through post-synthetic modification, the transformation of C O bonds to C S bonds can be facilely realized via Lawesson reagent, leading to the activity enhancement of the COF surface due to the higher activity of C S to sodium. With these triplex structural enhancements, the resulting S@TAPT-COFs (sulfuretted 2,4,6-Tris(4-aminophenyl)-1,3,5-triazine) nanosheets cathode exhibits excellent SIBs performances with a high specific capacity of 109.3 mAh g−1 at 0.1 A g−1 and a long-term stability with 68.6 mAh/g specific capacity remaining after 2000 cycles of charge/discharge process at 2.0 A g−1. This three-in-one strategy integrating morphology control, molecular design and post-synthetic modification provides an effective route to inspire the development of novel organic electrodes especially COFs for sustainable and durable rechargeable batteries. [ABSTRACT FROM AUTHOR]

Here we report a mechanistic study on the diversity of assembled structures. We take the assembly of porphyrin molecules as an example to investigate how the diffusion of molecules influences the structure of assemblies. The diffusion is regulated by changing the composition of solvents. Diverse structures of porphyrin particles are assembled at various volume ratios of ethanol in water, including strip-like particles forming at 50%, tubular particles forming at 80% and rod-like particles forming at 95%. The in situ examination on the self-assembly process by confocal microscopy reveals that at the low volume ratio the nucleation initiates at the interface of emulsion followed by the growth of particles in the solvent. The diffusion limitation of molecules in the solvent is remarkable at the low volume ratio of ethanol as a result of high viscosity of the solvent and low solubility to the molecule, which enables the anisotropic growth of particles forming strip-like particles. With the increase of volume ratio of ethanol, the diffusion limitation is attenuated, leading to the thickening of particles and the formation of rod-like products. The thickening under diffusion limitation also causes a preferential growth of outer layer of particles resulting in the formation of hollow structures. The findings in this paper show that the diffusion of molecules plays an important role in shaping structures of assemblies, which was underestimated in previous studies. [ABSTRACT FROM AUTHOR]

In this study, CeO 2 with a broom-like porous hierarchical structure was successfully prepared by a simple template-free hydrothermal method. In the whole hydrothermal process, reaction time and temperature play important roles in morphology control. The morphology of the as-prepared samples was characterized by field emission scanning electron microscopy, transmission electron microscopy and high-resolution transmission electron microscopy. Structure information was obtained by using an X-ray diffractometer and Raman analysis. Analyses of elements and chemical valence analysis were carried on X-ray photoelectron spectroscopy. Absorption edge and band gap energy were investigated by UV–vis diffuse reflectance. In addition, the optimum experimental conditions for target products were determined. Compared with various morphology samples’ BET data, relative intensity of Raman peaks, catalytic evaluation, we can draw a conclusion that CeO 2 with a broom-like porous hierarchical structure has a higher concentration of oxygen vacancies that results in enhancement of catalytic activity. An Ostwald ripening process with orientative self-assembly was proposed for formation of the broom-like porous hierarchical structure. [ABSTRACT FROM AUTHOR]

Highlights: [•] The cotton-like Ca–Al–La composite was prepared by a simple one-step method. [•] The composite exhibited high fluoride removal rate in a wide pH range from 3 to 11. [•] The maximum adsorption capacity of the as-prepared samples is 26.17mg/g. [•] The composite still showed high adsorption capacity after four reuse cycles. [Copyright &y& Elsevier]

Abstract: Novel PbWO4 crystals with different morphologies, 14-faceted polyhedrons, hierarchical microspheres and nanoparticles, were fabricated by adjusting pH value under hydrothermal conditions. The as-prepared PbWO4 samples were characterized by nitrogen-physical adsorption, powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV–vis diffuse reflectance spectra, photoluminescence emission spectroscopy, and Fourier transform infrared spectroscopy. The photocatalytic performance of the PbWO4 crystals with different nanostructures in degradation of the acid orange II dye under UV light (365nm) was investigated. The plausible growth mechanisms for PbWO4 crystals with different morphologies were proposed. Photocatalytic tests showed that the performance of PbWO4 crystals strongly depended on their morphologies. PbWO4 microspheres with hierarchical nanostructures prepared under pH 7.0 at 140°C exhibited the highest activity and stability in recycling reaction. The degradation kinetics of dye over PbWO4 crystals was found to conform to the pseudo-first order model. The enhanced photocatalytic performance was attributed to the unique hierarchical nanostructures with high surface area and improved surface properties. Moreover, the high crystallinity of PbWO4 microspheres exhibited an enhanced catalytic activity owing to lower recombination rate of photo-generated electron/hole pairs. These novel hierarchical PbWO4 microspheres hold promise in applications of environmental purification. [Copyright &y& Elsevier]

Abstract: Large particle MCM-41 was synthesized using preshaped silica gel as the silica source. The physical properties of MCM-41 samples were characterized by X-ray diffraction (XRD), nitrogen physisorption, and field emission scanning electron microscopy (FESEM). The sample showed highly ordered mesoporous structure and spherical morphology with particle sizes of 20–45μm by pseudomorphic synthesis. The fluidization study showed that the MCM-41 with large particle size, for the first time, can be well fluidized because of the transformation from Geldart C to Geldart A classification. Furthermore, Co–Mo catalyst using large particle MCM-41 as support was successfully applied for the synthesis of single-walled carbon nanotubes (SWCNTs) in a fluidized-bed reactor. The product was monitored by thermogravimetric analysis (TGA), transmission electron microscopy (TEM), Raman and Fluorescence spectroscopy, which suggested the resulted semiconducting SWCNTs possess the narrow (n, m) distribution. [Copyright &y& Elsevier]

[Display omitted] • Hybrid nanostructure of RuO 2 and NiMoO was fabricated via highly matched lattices. • Integrated NiMoO works like a turbo through optimizing the intermediates adsorption. • RuO 2 -NiMoO exhibits enhanced electrocatalytic activity for overall water splitting. • The synergy among geometric, electronic, and interfacial structures is crucial. Cooperative promotions of intrinsic activity, active sites amount, and mass transfer/charge transport in electrocatalytic process are highly depending on the fundamental understanding of reaction mechanism and the systematic and elaborate designing of morphological, electronic, and interfacial structure of electrocatalyst. Herein, a hybrid nanostructure of RuO 2 strongly coupled with structurally controllable NiMoO wafer arrays was elaborately fabricated via highly matched lattices for superior alkaline water electrolysis through optimizing the adsorption energies of the key intermediates at the interface based on synergistic electronic, geometric, and interfacial effects. The incorporation of Mo ion can adjust the electronic structure of host NiO x endowing the resultant NiMoO with suitable H and O intermediate binding energy for active species transfer between the interfaces. The ratio of O/C on the surface of flexible carbon cloth was well tuned through O 2 -plasma to achieve the desired geometric structure of NiMoO wafers with features of rich porosity and abundant active site. The RuO 2 nanoparticles are homogeneously distributed on the surface of porous NiMoO wafers via highly matched lattices, thereby offering efficient interfacial synergy. Consequently, the hybrid nanostructure of Ru species and NiMoO exhibits greatly enhanced bifunctional electrocatalytic activities toward both HER and OER for overall water splitting. The integrated NiMoO wafer works like a turbo for engineering robust Ru-based bifunctional electrocatalyst. The finding may provide insights for the rational design of advanced nanocomposite catalysts for various energy conversion applications. [ABSTRACT FROM AUTHOR]

• Fabricating 3D-HPCS@MnO 2 nanohybrids with colony-like microstructures and rich heteroatom dopants. • Acting as templates, the graphitic edges of 3D-HPCS enable structural control of MnO 2 electrodeposits. • Quantitatively proved mesopores contributes more than micropores in increasing capacitance of HPCS. • Both surface capacitive and diffusion-controlled processes play roles in capacitive performance of HPCS@MnO 2. • The assembled device exhibits an energy density of 61.8 W h kg−1 and a maximum power density of 22.6 kW kg−1. Electrodeposition based on 3D scaffold-templates is a unique and facile method to tune the microstructure of composite electrode materials for energy storage devices. In this work, we developed a green process to fabricate 3D hierarchical porous carbon scaffold-MnO 2 (3D-HPCS@MnO 2) nanohybrids with colony-like microstructures. Acting as conductive template and pyrolysis accelerant, the 3D-HPCS enables microstructural control of MnO 2 electrodeposits and facilitates valence conversion from Mn2+ to Mn4+. Comparing with depositing on nickel foam, the morphology of MnO 2 changed from nanospheres to nanowrinkles when depositing on the 3D-HPCS templates. Benefiting from abundant forest-like micro/mesopores, the resultant 3D-HPCS possesses high specific surface area (1627 m2 g−1) and rich heteroatom dopants (6.94 wt%), affording a high gravimetric specific capacitance (231.5 F g−1) with outstanding cycling performance (95% capacitance retention after 10,000 cycles). The assembled asymmetric supercapacitor based on HPCS//HPCS@MnO 2 exhibits an energy density of 60.8 Wh kg−1 and a maximum power density of 20.7 kW kg−1. Our investigation has quantitatively proved that mesopores contribute more than micropores in increasing capacitance of HPCS and both surface capacitive and diffusion-controlled processes play roles in capacitive performance of HPCS@MnO 2. Moreover, the influence of the morphology and surface functionality on the electrochemical performances of composite electrodes have been analyzed. [ABSTRACT FROM AUTHOR]