Publications by authors named "Qi Hua Fan"

Atmospheric plasma processing, which combines the efficacy of chemical processes and the safety of physical processes, has been used to modify the surface characteristics of graphite-based materials. In this work, two distinct plasma source gases, CF and O, with the addition of a rotary reactor were used. The effectiveness of modifying the basal plane of intercalated graphite nanoplatelets (GnP) was investigated with various analytical techniques and the visual observation of the dispersion of these plasma-treated GnP in solvents was also reported.

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The volume expansion of CoFe O anode poses a significant challenge in the commercial application of lithium/sodium-ion batteries (LIBs/SIBs). However, metal-organic-frameworks (MOF) offer superior construction of heterostructures with refined interfacial interactions and lower ion diffusion barriers in Li/Na storage. In this study, the CoFe O @carbon nanofibers derived from MOF are produced through electrospinning, in situ growth followed by calcination, which are then confined within an MXene-confined MOF-derived porous CoFe O @carbon composite architecture under alkali treatment.

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Ultra-thin silver films are susceptible to ambient environments and form grayish layers in the silver mirroring process. The poor wettability together with the high diffusivity of surface atoms in the presence of oxygen accounts for the thermal instability of ultra-thin silver films in the air and at elevated temperatures. This work demonstrates an atomic-scale aluminum cap layer on the silver to enhance the thermal and environmental stabilities of ultra-thin silver films deposited by sputtering with the assistance of a soft ion beam reported in our previous work.

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A single-beam plasma source was developed and used to deposit hydrogenated amorphous carbon (a-C:H) thin films at room temperature. The plasma source was excited by a combined radio frequency and direct current power, which resulted in tunable ion energy over a wide range. The plasma source could effectively dissociate the source hydrocarbon gas and simultaneously emit an ion beam to interact with the deposited film.

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Bistable liquid crystal (LC) shutters have attracted much interest due to their low energy consumption and fast response time. In this paper, we demonstrate an electrically tunable/switchable biostable LC light shutter in biological optics through a three-step easy-assembly, inexpensive, multi-channel shutter. The liquid crystal exhibits tunable transparency (100% to 10% compared to the initial light intensity) under different voltages (0 V to 90 V), indicating its tunable potential.

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The use of toxic components and short longevity greatly restricted the commercial application of superhydrophobic surfaces in oil-water separation, antifouling, and self-cleaning. To address these concerns, a durable, robust, and fluorine-free superhydrophobic fabric is prepared on account of inspiration of nature. In this work, submicrometer-sized silica particles with different particle sizes are deposited onto cotton fabrics, followed by hydrophobic modification of poly(dimethylsiloxane) (PDMS), and consequently bonded the substrate and coating via powerful covalent bonds through a simple dip-coating technique.

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Integrative neural interfaces combining neurophysiology and optogenetics with neural imaging provide numerous opportunities for neuroscientists to study the structure and function of neural circuits in the brain. Such a comprehensive interface demands miniature electrode arrays with high transparency, mechanical flexibility, electrical conductivity, and biocompatibility. Conventional transparent microelectrodes made of a single material, such as indium tin oxide (ITO), ultrathin metals, graphene and poly-(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS), hardly possess the desired combination of those properties.

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This paper reports on electrochemical and optical characteristics of flexible, transparent microelectrodes, which consist of thin poly-(3, 4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) spun onto indium-tin-oxide (ITO) electrodes for potential applications in biomedical optoelectronic devices. Although PEDOT:PSS/ITO combined films have been extensively investigated for applications in optical devices, such as solar cells and LEDs, PEDOT:PSS/ITO films for use in electrophysiological recording have not been well-characterized yet. In this work, PEDOT:PSS coated ITO microelectrodes with various diameters of 10 μm, 37 μm, 50 μm and 80 μm were microfabricated and characterized, and their properties were compared with plain ITO microelectrodes.

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Highly reflective coatings with strong light scattering effect have many applications in optical components and optoelectronic devices. This work reports titanium dioxide (TiO(2)) pigment-based reflectors that have 2.5 times higher broadband diffuse reflection than commercially produced aluminum or silver based reflectors and result in efficiency enhancements of a single-junction amorphous Si solar cell.

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