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This study describes the structural modifications of char electrodes and the resulting carbon nanoparticles using method of arc discharge in liquid method, an approach which is simpler and less expensive than other techniques such as CVD and laser vaporization. The nanoparticles are obtained from powder floating on the water surface during arc discharge between two electrodes submerged in water. X-ray diffraction analysis (XRD) profiles show peak formation at 24-26o 2Ѳ, associated with hexagonal graphite structure.Transmission electron microscopy (TEM) confirmed the presence of graphitic-structured nanoparticles after arc discharge; these nanoparticles have diameters ranging from 20 to 100 nm. In contrast, nanoparticles produced using graphite electrodes with current source variations show more complicated and varied stuctures, for example, structures such as nanoonions, graphene, and amorphous nanoparticles.

Herein we modified TiO2 anatase with carbon material using an electrical arc discharge technique in liquid medium to produce a nanoparticle of TiO2/Carbon photocatalyst. The electrical arc discharge was performed using two graphite electrodes submerged in TiO2 suspended in ethanol by passing electrical 20-40 V (10-50 A). X-ray Diffraction (XRD) peak profile analysis shows the successful modification confirmed from the presenting peaks which represent to crystalline TiO2 and carbon element. The fabrication was then followed by the assessment of photocatalytic activity of fabricated nanoparticles in methylebe blue degradation under mercury lamp irradiation. After 60 minutes irradiation, the photocatalytic activity of TiO2/Carbon increased more than three times higher compared to the photocatalytic activity of pristine TiO2.

This work aims to fabricate carbon-based nanomaterial using arc-discharge in liquid which is much simple and cheap compared to other techniques i.e., CVD, laser vaporization, etc. The experiment were performed using intermediate DC power supply (1300 W) to produce arc, and commercial graphite pencils (with 5 mm diameter) as negative and positive electrodes. Deionized water was used as heat absorber. The result shows that arc discharge in deionized water could effectively produce carbon nanomaterial (i.e., graphene and CNT). In adddition, finite element method-based simulation of different intercalating process of Li-ion to different shape of anode i.e., bulk and phorous anode materials for battery application is also presented in order to provide support for design of Li-ion battery based on carbon nanomaterial.

The interfacial shear strength (IFSS) between natural fibers and thermoplastics matrix is one of the key parameters to increase the mechanical properties of composites. IFSS can be improved by alkali treatment. Therefore, the research is to investigate the influence of IFSS soaking time in alkali solution of cantala fiber/Recycled High Density Polyethylene (RHDPE) composites. Experimentally, cantala fiber/RHDPE composites were manufactured by simple hot press machine. Alkali treatment on the surface of cantala fibers was carried out on 2% sodium hydroxide (NaOH) solution for a period time, i.e., 0, 4, 8, 12, 16, 20, and 24 hours. The IFSS value of composites was observed using single fiber pullout test method. The result shows that the increase of soaking time in alkali solution could improve IFSS of cantala fiber/RHDPE composites by 43%.

Kelvin probe force microscopy (KFM) working at low temperatures (13 K) is used to study local electronic potential fluctuations induced by individual phosphorus donors. Electronic potential maps were measured at the surface of thin phosphorus-doped channel of silicon-on-insulator field-effect transistors for different values of backgate voltage. We observed local changes of the potential profile with increasing backgate voltage, indicating electron injection in the channel. Single-step changes in the depth of the fine potential wells, observed by changing backgate voltage, are ascribed to single-electron charging in individual donors. For clusters of donors, with overlapped potential wells, electron charging occurs gradually, without single-step behavior, as the backgate voltage becomes more positive.

We have recently proposed and demonstrated a new device concept, “Si-based single-dopant atom device”, consisting of only one or a few dopant atoms in the channel of Si field-effect transistors. The device characteristics are determined by a dopant, which is mediating electron or hole transport between source and drain electrodes. In this paper, our recent results on electronic and photonic applications are introduced. Furthermore, single-dopant images obtained by a scanning probe microscope are also presented.

Low temperature Kelvin Probe Force Microscopy (LT-KFM) can be used to monitor the electronic potential of individual dopants under an electric field. This capability is demonstrated for silicon-on-insulator field-effect-transistors (SOI-FETs) with a phosphorus-doped channel. We show results of the detection of individual dopants in Si by LT-KFM. Furthermore, we also observe single-electron charging in individual dopants located in the Si channel region.

Non-degenerately doped lateral nanoscale p-n and p-i-n silicon-on-insulator devices have been fabricated and characterized at room temperature (297 K). In both types of devices, p-type Si substrate is used as a backgate to modify the potential in the top Si layer in both forward- and reverse-bias regimes. In the forward-bias regime, both types of devices exhibit negative differential transconductance (NDT), with the current peak position and level controlled by the backgate and anode voltage. In the reverse-bias regime, the devices exhibit a sharp current increase as a function of the backgate voltage, which is a signature of the band-to-band tunneling (BTBT) mechanism. These findings suggest that NDT and the sharp increase of current, induced by the contribution of the BTBT mechanism, can be achieved even in non-degenerately doped backgated diodes, which opens new possibilities for BTBT-based functionalities, benefiting from a simple design and CMOS compatibility.

The modification of carbon-based nanomaterials with metals is widely studied due to its unique properties. Here, the modification of carbon nanomaterial with iron oxide has been successfully carried out. This modification was achieved using arc discharge in 50% ethanol liquid media. The anode used in the arc discharge was prepared from a mixture of carbon and iron oxide that was synthesized in electrolysis and was then calcined at 250degC with silicon binder with a mass ratio of 3:1:1, and the cathode used was graphite rod. Both electrodes were set in the nearest gap that could provide an arc during arc-discharging, leading to carbon-based nanoparticle formation. The diffractogram pattern of the X-ray diffraction of the fabricated nanoparticles confirmed the typical peak of carbon, iron oxide and iron. The magnetization value of the result analysis of the vibrating sample magnetometer was 9.9 emu/g. The bandgap energy measurement using diffuse reflectance ultra violet was estimated to be 2.18 eV. Using the transmission electron microscopy, the structure of the nanomaterial produced was observed as carbon-encapsulated iron compound nanoparticles.