Browsing by Author "Sha, Junwei"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Rivet Graphene(American Chemical Society, 2016) Li, Xinlu; Sha, Junwei; Lee, Seoung-Ki; Li, Yilun; Ji, Yongsung; Zhao, Yujie; Tour, James M.; NanoCarbon CenterLarge-area graphene has emerged as a promising material for use in flexible and transparent electronics due to its flexibility and optical and electronic properties. The anchoring of transition metal nanoparticles on large-area single-layer graphene is still a challenge. Here, we report an in situ preparation of carbon nano-onion-encapsulated Fe nanoparticles on rebar graphene, which we term rivet graphene. The hybrid film, which allows for polymer-free transfer and is strong enough to float on water with no added supports, exhibits high optical transparency, excellent electric conductivity, and good hole/electron mobility under certain tensile/compressive strains. The results of contact resistance and transfer length indicate that the current in the rivet graphene transistor does not just flow at the contact edge. Carbon nano-onions encapsulating Fe nanoparticles on the surface enhance the injection of charge between rivet graphene and the metal electrode. The anchoring of Fe nanoparticles encapsulated by carbon nano-onions on rebar graphene will provide additional avenues for applications of nanocarbon-based films in transparent and flexible electronics.Item Three-dimensional (3D) printing of graphene materials(2024-04-30) Tour, James M.; Sha, Junwei; Li, Yilun; Miller, Jordan; Kinstlinger, Ian; Cofer, Savannah; Chyan, Yieu; Rice University; United States Patent and Trademark OfficeThree-dimensional (3D) printing of graphene materials and methods and apparatuses for making same. In some embodiments, combined metal powder and carbon growth sources (such as powder Ni and sucrose) are utilized in the 3D printing process. In other embodiments, metal powders with binders (such as powder Ni and a polymer bases binder) are utilized in the 3D printing process. The metal in the resulting 3D printed composite material can then be etched or otherwise removed yielding the 3D printed graphene materials.