Publications by authors named "Fangming Han"

Photocatalytic reduction of nitrate is a promising green strategy to remove nitrogen pollutants from water bodies. However, it is a considerable challenge to directly reduce nitrate using photogenerated electrons. In this work, a g-CN/Ag-nanoparticle composite demonstrating high catalytic activity toward nitrate is constructed using an photodeposition method.

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The trade-off between compact energy storage and high-power performance presents a significant challenge in device development. While densifying carbon materials enhances volumetric energy density by optimizing the balance between porosity and packing density, it often disrupts electronic conductivity due to random physical contact between nanomodules, limiting the power performance. This work presents a sodium alginate (SA)-induced self-shrinkage densification strategy that overcomes this limitation by incorporating nanometer-sized "spacers," namely carbon quantum dots (CQDs), into graphene nanosheets and crosslinking them by carbonizing SA accompanying with the shrinkage.

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Herein, a stable and ultra-sensitive rutin electrochemical sensor was successfully developed. This sensor based on glassy carbon electrode (GCE) modified with C-GCS@ZIF-F/PL nanocomposite, which was made of thermally carbonized glucose (GCS) doped with flower-like ZIF (ZIF-F) and pencil lead (PL). The electrochemical response of rutin was considerably significant at C-GCS@ZIF-F/PL/GCE, demonstrating favorable conductivity and electrocatalytic properties for detection of rutin.

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Electric double-layer capacitors (EDLCs) with fast frequency response are regarded as small-scale alternatives to the commercial bulky aluminum electrolytic capacitors. Creating carbon-based nanoarray electrodes with precise alignment and smooth ion channels is crucial for enhancing EDLCs' performance. However, controlling the density of macropore-dominated nanoarray electrodes poses challenges in boosting the capacitance of line-filtering EDLCs.

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To date, the excellent mass-catalytic activities of Pt single-atoms catalysts (Pt-SACs) toward hydrogen evolution reaction (HER) are categorically confirmed; however, their high current density performance remains a challenge for practical applications. Here, a binder-free approach is exemplified to fabricate self-standing superhydrophilic-superaerphobic Pt-SACs cathodes by directly anchoring Pt-SAs via Pt-NC coordination bonds to the structurally-integrated 3D nitrogen-doped carbon tubes (N-CTs) array grid (denoted as Pt@N-CTs). The 3D Pt@N-CTs cathode with optimal Pt-SACs loading is capable of operating at a high current density of 1000 mA cm with an ultralow overpotential of 157.

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Filter capacitors play a critical role in ensuring the quality and reliability of electrical and electronic equipment. Aluminum electrolytic capacitors are the most commonly used but are the largest filtering components, limiting device miniaturization. The high areal and volumetric capacitance of electric double-layer capacitors should make them ideal miniaturized filter capacitors, but they are hindered by their slow frequency responses.

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It is of great significance to develop a simple and effective method for constructing large-scale high-quality surface-enhanced Raman scattering (SERS) substrate. Here, an Ag nanoparticle-assembled micro-bowl array was prepared by a close-packed polystyrene (PS) sphere monolayer templated electrodeposition approach. The fabricated Ag nanoparticle-assembled micro-bowl array shows high SERS sensitivity to rhodamine 6G (R6G) under an ultra-low concentration of 1 fM, and exhibits excellent SERS spectral uniformity with a small relative standard deviation (RSD) of 7.

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Polycyclic aromatic hydrocarbons (PAHs) are one of the most widespread and dangerous group of pollutants existing in the environment. Trace detection of PAHs is essential and important. Surface-enhanced Raman scattering (SERS) is a powerful analytical tool for ultrasensitive chemical analysis.

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An ordered array of hierarchically-structured core-nanosphere@space-layer@shell-nanoparticles has been fabricated for surface-enhanced Raman scattering (SERS) detection. To fabricate this hierarchically-structured chip, a long-range ordered array of Au/Ag-nanospheres is first patterned in the nano-bowls on the planar surface of ordered nanoporous anodic titanium oxide template. A ultra-thin alumina middle space-layer is then conformally coated on the Au/Ag-nanospheres, and Ag-nanoparticles are finally deposited on the surface of the alumina space-layer to form an ordered array of Au/Ag-nanosphere@Al2O3-layer@Ag-nanoparticles.

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Ordered arrays of Au-nanorod-tips protruding from an anodic aluminum oxide (AAO) template are reported as reproducible and active surface-enhanced Raman scattering (SERS) substrates. The Au-nanorods were grown in the nanochannels of the AAO template by use of alternative current electrodeposition, then the template was strengthened using a polymer, and finally the template bottom side was selectively etched to expose the Au-nanorod tips. By controlling the thinning of the AAO-porewalls, the inter-nanorod-gaps were tuned to ~5 nm, forming dense and uniform nano-gap induced "hot spots" among the adjacent Au-nanorod tips.

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Hierarchical assembly of plasmonic nanostructures can induce high surface-enhanced Raman scattering (SERS) activity. However, it is a challenge to uniformly disperse the hierarchical nanostructures onto a planar substrate to achieve SERS signal reproducibility. This report presents a facile route to fabricate a hexagonally patterned flower-like silver particle array as the SERS substrate.

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Dielectric capacitors are promising candidates for high-performance energy storage systems due to their high power density and increasing energy density. However, the traditional approach strategies to enhance the performance of dielectric capacitors cannot simultaneously achieve large capacitance and high breakdown voltage. We demonstrate that such limitations can be overcome by using a completely new three-dimensional (3D) nanoarchitectural electrode design.

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Nanocontainers have great potentials in targeted drug delivery and nanospace-confined reactions. However, the previous synthetic approaches exhibited limited control over the morphology, size and materials of the nanocontainers, which are crucial in practical applications. Here, we present a synthetic approach to multi-segment linear-shaped nanopores with pre-designed morphologies inside anodic aluminium oxide (AAO), by tailoring the anodizing duration after a rational increase of the applied anodizing voltage and the number of voltage increase during Al foil anodization.

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We present a surface-enhanced Raman scattering (SERS) substrate featured by large-scale homogeneously distributed Ag nanoparticles (Ag-NPs) with sub-10 nm gaps assembled on a two-layered honeycomb-like TiO(2) film. The two-layered honeycomb-like TiO(2) film was achieved by a two-step anodization of pure Ti foil, with its upper layer consisting of hexagonally arranged shallow nano-bowls of 160 nm in diameter, and the lower layer consisting of arrays of about fifty vertically aligned sub-20 nm diameter nanopores. The shallow nano-bowls in the upper layer divide the whole TiO(2) film into regularly arranged arrays of uniform hexagonal nano-cells, leading to a similar distribution pattern for the ion-sputtered Ag-NPs in each nano-cell.

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Silicon, being in the same group in the periodic table as carbon, plays a key role in modern semiconductor industry. However, unlike carbon nanotube (NT), progress remains relatively slow in silicon NT (SiNT) and SiNT-based heteroarchitectures, which would be the fundamental building blocks of various nanoscale circuits, devices, and systems. Here, we report the synthesis of linear and branched crystalline SiNTs via porous anodic aluminum oxide (AAO) self-catalyzed growth and postannealing, and the connection of crystalline SiNTs and gold nanowires (AuNWs) via a combinatorial process of electrodepositing AuNWs with predesired length and location in the channels of the AAO template and subsequent AAO self-catalyzed and postannealing growth of SiNTs in the remaining empty channels adjacent to the AuNWs.

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