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Bioactive degradable scaffolds that facilitate bone healing while fighting off initial bacterial infection have the potential to change established strategies of dealing with traumatic bone injuries. To achieve this a composite material made from calcium phosphate graphene (CaPG), and MXene was synthesized. CaPG was created by functionalizing graphene oxide with phosphate groups in the presence of CaBr with a Lewis acid catalyst. Through this transformation, Ca2+ and PO43− inducerons are released as the material degrades thereby aiding in the process of osteogenesis. The 2D MXene sheets, which have shown to have antibacterial properties, were made by etching the Al from a layered Ti3AlC2 (MAX phase) using HF. The hot‐pressed scaffolds made of these materials were designed to combat the possibility of infection during initial surgery and failure of osteogenesis to occur. These two failure modes account for a large percentage of issues that can arise during the treatment of traumatic bone injuries. These scaffolds were able to retain induceron‐eluting properties in various weight percentages and bring about osteogenesis with CaPG alone and 2 wt% MXene scaffolds demonstrating increased osteogenic activity as compared to no treatment. Additionally, added MXene provided antibacterial properties that could be seen at as little as 2 wt%. This CaPG and MXene composite provides a possible avenue for developing osteogenic, antibacterial materials for treating bone injuries. [ABSTRACT FROM AUTHOR]

Large area single and bilayer graphene are grown on Pt/Ti/SiO2 substrates by hot filament chemical vapor deposition (HFCVD) with and without the assistance of Cu foil. The quality and number of graphene layers deposited on the substrate are assessed by Raman Spectroscopy. Atomic Force Microscopy (AFM) is used for assessing the surface topography of the graphene films grown on the Pt/Ti/SiO2 substrates. The microstructure and elemental analyses are performed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The results show that bilayer graphene growth is facilitated by a copper foil placed nearby Pt/Ti/SiO2 substrate and by a high filament temperature in the HFCVD reactor. Monolayer graphene grows only when no copper foil is placed near the Pt/Ti/SiO2 substrate at a low filament temperature. The approach paves a novel pathway towards the layer‐controlled growth of graphene on Pt/Ti/SiO2 substrates by HFCVD for frontier applications. [ABSTRACT FROM AUTHOR]

Thermal chemical vapor decomposition of methane on copper is the most widely employed technique for high quality and large area graphene growth. Graphene growth by this technique tends to be limited to a monolayer owing to the surface mediated self-limiting growth mechanism, and hence, it is difficult to obtain continuous bilayers and multilayers. We report the layer-controlled growth of high quality and large area polycrystalline graphene on copper foil in a hot filament chemical vapor deposition (HFCVD) reactor and demonstrate that graphene can be grown with a controlled grain size in the range of 5–16 μm. The field effect hole mobilities of the largest grain monolayer and bilayer graphene and the thickest few-layer graphene are 4310 ± 348, 2745 ± 276, and 2472 ± 185 cm2V–1s–1, respectively, which are comparable to that of high quality polycrystalline graphene and suitable for future nanoelectronics. The results of the systematic parametric study hereby presented indicate that graphene adlayers grow on top of the previously grown layer(s) and show that the HFCVD growth of graphene overcomes the difficulties to growing layer-controlled-graphene on copper. Copper vapor together with carbon radicals produced at the filaments appear to enable the adlayer graphene formation. The versatility and capability of the HFCVD for facile and inexpensive growth of graphene make it a superior technique for industrial applications. [ABSTRACT FROM AUTHOR]

We demonstrate the hybrid fabrication process of a graphene integrated highly transparent resistive random-access memory (TRRAM) device. The indium tin oxide (ITO)/Al2O3/graphene nonvolatile memory device possesses a high transmittance of >82% in the visible region (370-700 nm) and exhibits stable and non-symmetrical bipolar switching characteristics with considerably low set and reset voltages (<±1 V). The vertical two-terminal device shows an excellent resistive switching behavior with a high on-off ratio of ∼5 × 103. We also fabricated a ITO/Al2O3/Pt device and studied its switching characteristics for comparison and a better understanding of the ITO/Al2O3/graphene device characteristics. The conduction mechanisms in high and low resistance states were analyzed, and the observed polarity dependent resistive switching is explained based on electro-migration of oxygen ions. [ABSTRACT FROM AUTHOR]

We report photovoltaic response of highly transparent graphene/BiFe0.95Si0.05O3 (BFSiO)/ITO/ glass derived from bottom-up spin coating technique. The device exhibits short-circuit-current (ISC 0.75 mA) with 1000 fold upsurge and open-circuit-voltage (VOC∼0.45 V) under standard AM 1.5 illumination through graphene. In combination, ISC of 0.63mA and VOC of 0.35V for same illumination through ITO, reveals the prospects of harvesting indoor light. Also, crystallographic structure, red shift in band gap, leakage behavior, and ferroelectric characteristics of BFSiO thin films are reported. Reproducible transient response of ISC and VOC with quick switching (<100 ms) for 20 consecutive cycles and stability (95%) over test period of 16 weeks signifies high endurance and retentivity, promising for building integrated self-powered windows. [ABSTRACT FROM AUTHOR]