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Highlights: [•] Novel hierarchical macroporous PPy–TiO2 composite nanostructures. [•] Synergetic interaction between PPy and TiO2 for effective charge pair separation. [•] Improved photoactivity for degradation of MB under simulated sun light irradiation. [•] High H2O2 detecting sensitivity with appropriate PPy content in composites. [•] Dispersed PPy nanoparticles by etching the composites with HF acid. [Copyright &y& Elsevier]

Abstract: A novel core–shell sphere with controlled shell thickness was synthesized by in situ chemical oxidative polymerization of pyrrole on FTS (Fe2O3/TiO2/SiO2 composite) surface. The dual porosity of 2–3nm and 40–50nm in FTS core particle provides the hybrids with a high surface area to volume ratio, which enormously facilitates the molecule diffusion process. Furthermore, the porous FTS particle encapsulate Fe2O3 and TiO2 leading to its synergetic interaction with the PPy coating based on FTIR analysis. The unique structure and composition of the hybrid spheres result in new sensing property that is not available from their single counterparts. Cyclic voltammetry results demonstrate that the spheres with appropriate concentration of PPy exhibit enhanced electrocatalytic activity toward the reduction of H2O2 in 0.1M phosphate buffer solution. The sensing performance tests show that the hybrids possess good linear response in wide H2O2 concentration range (10–4000μM) and high sensitivity to H2O2 (0.653AM−1 cm−2) at room temperature. The formation mechanism of the spheres was proposed based on the fact that the FTS core was coated firstly by a smooth PPy layer and then PPy nanoparticles. The work reported here provides an alternative concept for preparation of functional materials with new nanostructures and properties. [Copyright &y& Elsevier]

Abstract: ZnO nanostructures with different morphologies and optical properties were prepared by a simple microemulsion process, and PEG400 was used as a directing agent. The samples were characterized by TEM, XRD, FTIR, and TG-DTA analysis. The XRD spectra indicate that the ZnO crystal has a hexagonal wurtzite structure. Needle-like, columnar, and spherical ZnO samples were synthesized respectively with the increase of PEG400 concentration in Zn(NO3)2 solution. TEM images and thermogravimetric analysis reveal that the microemulsion interface and the PEG400 agent have a synergistic effect on the morphology and crystalline size transition of ZnO nanostructures. The optical properties of the samples were investigated by measuring the UV–Vis absorbance spectra at room temperature. All the samples exhibit strong UV absorption at around 365 nm. ZnO products with band gap energies at 3.06, 3.02, 2.95, and 2.85 eV were obtained with 0, 12.5, 25.0, and 50.0% of PEG400 in Zn(NO3)2 solution, respectively. The formation mechanism of the ZnO nanostructures was proposed and discussed in detail. The synergistic control of the microemulsion interface and the agent on the growth of crystal nuclei reported here provides an alternative approach for preparation of other well-defined nanostructures. [Copyright &y& Elsevier]

[Display omitted] • Highly exposed isolated FeN 5 sites are embedded in N-doped carbon frameworks. • FeN 5 exhibits a maximum FE CO of 98% and over 95% from −0.4 to −1.0 V vs. RHE. • The axial coordinated N modulates the d -band center and facilitates CO desorption. • FeN 4 and axial coordinated N act synergistically to boost CO 2 -to-CO conversion. Electrochemical CO 2 conversion offers a sustainable approach to alleviate the energy crisis but remains a long-standing challenge. Herein, atomically dispersed FeN 5 sites anchored on N-doped carbon matrix templated by zeolitic imidazole framework-8 (ZIF-8) are facilely synthesized for efficient catalyzing CO 2 reduction. The FeN 5 single-atom catalyst (Fe-SA/ZIF) presents the Faradaic efficiency of 98% at −0.7 V vs. RHE and over 95% in a wide potential range from −0.4 to −1.0 V vs. RHE, surpassing most of the reported single-atom catalysts for CO 2 RR. Further density functional theory (DFT) calculations reveal that the outstanding activity of FeN 5 sites mainly originates from the lowered d -band center modulated by the out-of-plane coordinated pyridinic N, which reduces the CO adsorption energy from −1.71 to −1.49 eV compared to FeN 4 moieties. Thus, the synergistic effect between FeN 4 sites and the coordinated pyridine offers new insight in designing outstanding electrocatalysts for multiple applications. [ABSTRACT FROM AUTHOR]

Inspired by 'Hufu' in ancient China, we manufactured semiflexible micro crystallizer with two aspectant sessile platforms by 3D-printing technique that can construct a series of heteromorphic droplets (HDs) via stretching droplet height. By coordinating the gas–liquid interface and flow intensity (i.e., Ra/Ma), central-converging micro-flows were generated, which dominated solute and particle motion towards droplet center. Efficient harvest of single cubic NaCl crystal was achieved at platform center under wide volume and concentration ranges. [Display omitted] Droplet crystallization behavior held great potential in crystal preparation, micromaterial engineering, and molecular assembly. However, restricted by natural surface tension, the intrinsic crystallization regulation and efficient harvest of high quality crystal in diverse droplet features were still a great challenge. Herein, we developed a 3D printed semiflexible micro crystallizer with two aspectant sessile platforms that could simultaneously construct a series of heteromorphic droplets (HDs) and controllable HD shape. By shaping HD on the interface of the platform, central-converging micro-flows were generated by coordinating the gas–liquid interface and flow intensity (i.e., Ra/Ma) during HD crystallization from 'barrel', 'can', to 'sand clock' shape, which was validated via simulative and experimental research. Therefore, HDs, constructed in semiflexible micro crystallizer, exhibited efficient screening (>70 %) of single cubic crystal just at the center zone of platform, even under wide ranges of concentration and volume, manifesting excellent repeatability on high quality crystal harvest and relevant interfacial science research. [ABSTRACT FROM AUTHOR]

Hierarchically porous CNT@NC@GCN membranes with high porosity of 85% are fabricated facilely, the 3D hierarchical porous network can provide broad reaction interface and active sites for LiPSs anchoring. Furthermore, the uniform GCN layer can significantly improve the metallicity and conductivity of the frameworks, and strengthen Li+ and electron transport. The abundant N in the GCN coating can enrich active sites in the membrane for adsorption and catalysis conversion of LiPSs and Li 2 S at a low energy barrier. [Display omitted] Various challenges remain to be overcome in lithium-sulfur (Li-S) batteries, including the volume expansion and low conductivity of sulfur, the shuttle effect of lithium polysulfides and the sluggish redox reaction in the cell. Herein, we propose a multilayered conductive framework by the in situ growth of a conformal graphene-like C 3 N 4 (GCN) coating on porous CNT@NC networks with carbon nanotubes (CNTs) as the core and N -doped carbon (NC) as the crosslinking shell. The abundant N in the GCN coating increased the surface N concentration of the framework from 14.38% to 18.77%, which enriched the active sites in the frameworks for the adsorption and catalysis conversion of LiPSs and Li 2 S with a low energy barrier. Furthermore, the scalable frameworks can provide an 85% porosity for a sufficient reaction interface and accommodate the volume expansion of sulfur. The synergistic effect between GCN and the highly conductive hierarchical structure can accelerate the transport of Li+ and electrons as well as the diffusion of electrolyte. Benefitting from the above advantages, the Al-free CNT@NC@GCN electrode exhibits a reversible capacity of 647.6 mAh g−1 after cycling for 450 cycles at 1C with a low capacity fading rate of 0.09% per cycle. This proposed facile strategy creates inspiring insights into the design of novel cathode materials for Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of Co SACs were synthesized with tunable Co-N 5- x C x (x = 1, 2, 3) sites. • Engineering the hybrid N and C coordination greatly affect the CO 2 RR performance. • FE CO boosted from 54 to 76 and 92% at −0.8 V with increased ratio of Co-C. • Co-C promotes the electron donation and strengthen binding interaction with *COOH. Single-atom catalysts (SACs) with well-defined active sites provide an efficient route for catalyzing CO 2 reduction reaction (CO 2 RR). Although enormous attention has been focused on metal-N x moieties, understanding the effect of metal-C coordination and engineering of the hybrid metal-N/C sites have rarely been reported. Herein, we fabricated Co SACs with tunable isolated Co-N 5-x C x (x = 1, 2, 3) sites supported on porous carbon frameworks. Benefiting from the difference in electronegativity of the coordinated N and C atoms, the CO Faradaic efficiency (FE CO) enhanced considerably from 54% to 76% and 92% at −0.8 V vs. RHE for Co-N 4 C 1 , Co-N 3 C 2 , and Co-N 2 C 3 , respectively. Further density functional theory (DFT) calculations uncover that the increased ratio of Co-C coordination induced electron enrichment of Co atoms and upper-shift the d -band center to near Fermi level, and thus favorably promotes the electron-donating ability of Co centers and strengthens the adsorption of *COOH. [ABSTRACT FROM AUTHOR]

• High-throughput ALMS-qPCR method enhanced Nosema spp. detection. • DNA preparation of ALMS-qPCR is fast, automatable, and cost-effective. • Common PCR inhibitory factors were overcome in ALMS-qPCR. • The limit of detection (LOD) was 0.045 parasites/μL. • ALMS-qPCR is promising for routine pébrine screening and epidemiological studies. Accurate diagnosis of pathogenic Nosema spp. in Antheraea pernyi samples is considered especially useful for reducing economic losses in sericulture and improving food safety by maintaining pathogen-free pupae. However, microscopy and immunologic methods have poor diagnostic sensitivity, while the more sensitive PCR methods remain costly and time-consuming for template preparation. To address this issue, we introduce a sensitive ALMS-qPCR method that combines fast, simple DNA extraction using A lkali L ysis followed by M agnetic bead S eparation (ALMS) and quantitative real-time PCR (qPCR). This approach is especially fit for large-scale pathogen molecular screening, because the DNA preparation procedure is fast (<0.94 min per sample) and is high-throughput (performs on a 96-well plate). It is cost-effective, since the most expensive materials can be made in the lab and can be recycled, while the automated procedure can help to minimize labor cost. Though the DNA preparation procedure was substantially simplified, common PCR inhibitory factors were not observed. The sensitivity of ALMS-qPCR is high and the limit of detection is 0.045 parasites/μL. Large-scale screening of Nosema spp. in 3000 Antheraea pernyi samples confirmed the efficacy of the ALMS-qPCR method. Sensitivity is much higher than clinical microscopy, especially for host groups with low infection prevalence and levels. High-throughput ALMS-qPCR, combining automated DNA preparation and sensitive qPCR, provides an enhanced approach for pébrine screening and epidemiological studies. The application of ALMS-qPCR in the sericulture industry will help to strengthen pébrine control and breed pathogen-free species, which means much safer food provision and better genetic resource conservation. [ABSTRACT FROM AUTHOR]