KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Access type: UnknownSubject: search.filters.subject.heterostructure

Search Results

Now showing 1 - 2 of 2
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Alkanolamine-Grafted and Copper-Doped Titanium Dioxide Nanosheets-Graphene Composite Heterostructure for CO2 Photoreduction
    (2023-11-13)
    Karawek, Apisit
    ;
    Kitjanukit, Nutkamol
    ;
    Neamsung, Wannisa
    ;
    Kinkaew, Chonlathon
    ;
    Phadungbut, Poomiwat
    CO<inf>2</inf> photoreduction is an intriguing approach to carbon capture, utilization, and storage (CCUS). It relies on an effective photocatalyst to generate photoinduced electrons that incorporate carbon dioxide (CO<inf>2</inf>), yielding fuel products, e.g., methane, methanol, and ethanol. The heterostructure of titanium dioxide nanosheets (TNS) and graphene oxide (GO) is a sandwich-type composite consisting of two 2-dimensional nanostructures (2D-2D). It was demonstrated as an excellent candidate for CO<inf>2</inf> photoreduction due to its outstanding charge separation ability. This research studied the photoactivity of alkanolamine-grafted TNS and alkanolamine-grafted and copper-doped TNS/GO composites. In the first experiment, triethanolamine-grafted TNS (TEA-TNS) exhibited the best ability in CO<inf>2</inf> photoreduction compared to monoethanolamine- and diethanolamine-grafted TNS (MEA-TNS and DEA-TNS) due to the base-catalyzed hydration nature of CO<inf>2</inf>-TEA interactions. In the second experiment, we studied the photoactivity of four composites, including copper-doped TNS/GO (Cu-TNS/GO), TEA-[Cu-TNS/GO] (grafting TEA on Cu-TNS/GO), Cu-[TEA-TNS]/GO (doping Cu on TEA-TNS/GO), and TEA-Cu-TNS/GO (one-step hydrothermal synthesis with the Cu precursor, TEA, and GO). TEA-[Cu-TNS/GO] showed the best photoactivity since TEA was added last to the heterostructures, which benefited in avoiding side chelation reactions between TEA and Cu ions and ensuring TEA exposure to CO<inf>2</inf>
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Electrically Inert h-BN/Bilayer Graphene Interface in All-Two-Dimensional Heterostructure Field Effect Transistors
    (2018-08-29)
    Uwanno, Teerayut
    ;
    Taniguchi, Takashi
    ;
    Watanabe, Kenji
    ;
    Nagashio, Kosuke
    Bilayer graphene field effect transistors (BLG-FETs), unlike conventional semiconductors, are greatly sensitive to potential fluctuations because of the charged impurities in high-k gate stacks because the potential difference between two layers induced by the external perpendicular electrical filed is the physical origin behind the band gap opening. The assembly of BLG with layered h-BN insulators into a van der Waals heterostructure has been widely recognized to achieve the superior electrical transport properties. However, the carrier response properties at the h-BN/BLG heterointerface, which control the device performance, have not yet been revealed because of the inevitably large parasitic capacitance. In this study, the significant reduction of potential fluctuations to ∼1 meV is achieved in an all-two-dimensional heterostructure BLG-FET on a quartz substrate, which results in the suppression of the off-current to the measurement limit at a small band gap of ∼90 meV at 20 K. By capacitance measurement, we demonstrate that the electron trap/detrap response at such heterointerface is suppressed to undetectable level in the measurement frequency range. The electrically inert van der Waals heterointerface paves the way for the realization of future BLG electronics applications.