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The photovoltaic performance of Dye-sensitized Solar Cells (DSSC) could be optimized by playing the working area of the mesoporous TiO2 photoanode. A small working area will enhance the photovoltage and power conversion efficiency. In comparison, a large working area will improve the recombination rate and reduce the photon particle transport rate at the photoanode. The TiO2 based photoanode layer consists of a blocking layer and mesoporous paste deposited using spin coating and screen printing technique, respectively with various working areas of 0.25, 0.30, and 0.56 cm2. The cells were characterized using XRD, SEM-EDX, UV-Vis spectroscopy, and solar simulator. XRD confirmed that the TiO2 was in the anatase phase. SEM image represented a high surface area of mesoporous TiO2 indicated by porosity level up to 70%. The elemental analysis of TiO2 using EDX observed the presence of Ti and O peaks. The TiO2 mesoporous-based photoanode immersed in 0.07 mM of N719 solution possessed an absorbance range in the ultraviolet to the visible light. The working area of 0.25 cm2 exhibited a promising power conversion efficiency of 2.02% with a circuit current density of 10.8 mA/cm2 under an illumination light of 100 mW/cm2.

Photo-supercapacitor (PSc) was an integration of photovoltaic as a device for harvesting light energy and supercapacitor as an energy storage device. Multifunctional harvesting device has increasing demand in the green energy industry sector. In this study, we demonstrate the integrated array of photovoltaic type dye-sensitized solar cells and carbon-based supercapacitors. The photo-supercapacitor integration will be arranged in a different arrangement, called series and parallel arrangement. DSSC photoanode was used TiO2material that deposited using screen printing method on FTO substrate. Activated Carbon/Carbon Black/SBR as a material composite of the electrode was deposited on the aluminium foil substrate using dr. blade technique. XRD characterization has identified the TiO2anatase. The morphology of mesoporous TiO2 and Ti element has been identified by SEM characterization and EDX of 64.30 wt%. The UV-Vis spectroscopy curve has identified the absorbance in the wavelength range of 200 – 900 nm and the absorbance area of 914.58. The J-V characterization shows that TiO2 photoanode has a efficiency of 2.15 %. The Charge-Discharge shows that AC/CB/SBR performance has capacitance specific of 61.33 F/g. The l–-V characterization of photo-supercapacitor performance was arranged by series has voltage higher than parallel arrangement, because it produces a larger voltage (Vop ).

The Newton’s laws cannot be separated from mechanics and real life phenomenon, but research is rarely done on improving understanding of Newton’s law through ADI-Phenomenon-AF. The purpose of the research was to compare the effectiveness between ADI-Phenomenon-AF and ADI models in building understanding of Newton’s law and describing students’ difficulties after the learning process. This study used a mixed method design with an embedded experimental design. The instrument of this study was Newton’s law Understanding Test in the form of reasoned multiple-choice questions with a reliability of 0.817. The research data were analyzed by Wilcoxon test, Mann-Whitney U test, N-gain, d-effect, and a description of the reasons for students’ answers. The results show that both models are effective in building students’ understanding, but the ADI-Phenomenon-AF model is more effective than the ADI model. After the learning process the students of both classes still have difficulty in analyzing the relationship between acceleration, force, and mass. In addition, ADI-Phenomenon-AF class students still have difficulty with the nature of force in Newton’s first law, while the ADI class analyzes the application of Newton’s first and second laws.

Many supercapacitor studies focus on materials that are inflexible and have low specific capacitance. The addition of low dimension metals such as silver nanoparticles (AgNP) into the BaTiO3-Graphite-Activated Carbon (AC)/Aluminum foil showed a change in structure and morphology. The AC and graphite are generally used as necessary materials for supercapacitors. Adding AgNP is expected to increases the general mobility and specific capacitance of BaTiO3-Graphite-AC/Aluminum foil. In this study, we report the effect of AgNP into Graphite-AC-BaTiO3/Al foil symmetric supercapacitors. In the first step, we prepared nanocomposite comprises (x)AgNP-graphite-AC-BaTiO3. The dense solution then deposited on to clean aluminum foil as an electrode. The symmetric supercapacitors were sandwiched using two electrodes separated by a separator and electrolyte. It is shown that the crystal structure and morphology change with the addition of AgNP. The Optimum capacitance of Ag-BaTiO3-Graphite-AC/Aluminum Foil supercapacitor obtained from LCR meter of 1.9×10−5 F/g and dielectric constant of 1.03×106. The cyclic voltammetry test for three-electrode systems produces a specific capacitance of 8.95 F/g and 0.83 F/g for testing two electrode systems. We obtained that the increase of AgNP increases the specific capacitance of the electrode and supercapacitor to the optimum at 0.06 g Ag.

Many studies on symmetric capacitors have been extensively conducted. Not only the specific capacitance and energy density, but release rate energy are also necessary. Thus, continuous research is needed to improve capacitor performance by modifying ZnONP (nanoparticles) to ZnONR (nanorods) because the surface area of ZnONR is higher than ZnONP so that the interaction performance may increase. The spin coating speed needed to find out the appropriate ZnONR levels and morphology influencing supercapacitor performance. This research is focused on the influence of spin coating speed on the structure, morphology, and electrochemical performance of ZnONR/Aluminum foil electrodes. The deposited content, microstructure, and morphology of ZnONR are strongly influenced by the coating process. ZnONP coating on the surface of the substrate was carried out at a spin coater speed of 1500, 2500, and 3000 rpm. As the spin-coating speed increases, the porosity also increases, while the size of the grain, crystallinity, and specific capacitance reduce. Therefore, the best performance is shown by the lowest speed of 1500 rpm with the condition show ZnONR more deposited, and porosity, the highest cycle stability, and the specific capacitance reach to 0.0086 F/g with energy density 0.00433 Wh/g.

In this work, the synthesis of iron chromite nanoparticles was performed employing Indonesian iron sand through the coprecipitation route. The crystal and molecular structures of the prepared iron chromite nanoparticles were characterized by means of XRD and FTIR spectrophotometer. Meanwhile, the elemental mapping and morphology of the samples were evaluated using the SEM-EDX technique. The data analysis results showed that the iron chromite nanoparticles had a spinel cubic structure with the lattice parameters and crystallite size of 8.303 Å and 6.8 nm, respectively. The molecular structure analysis for the FTIR spectrum showed that the Fe and Cr ions placed the tetrahedral and octahedral sites. The average particle size of the iron chromite nanoparticles was 30.4 nm and tended to agglomerate. Interestingly, the elemental mapping indicated that the Fe, Cr, and O atoms distributed homogenously.

Perovskite solar cells have attracted the researchers' attention because they are one of the most promising candidates that are cheap, easy to fabricate and high-efficiency solar cell. ZnO nanorods (ZnO NRs) can be used as an electron and hole recombination barrier to improve the perovskite solar cell performance. This research aimed to investigate the effect of growing time on the characteristics of ZnO NRs and its application for perovskite solar cell device. The ZnO NRs was synthesized on ITO substrate by hydrothermal method at the different growing times of 4, 6, and 8 hours. The CH3NH3PbI3 perovskite solar cells were deposited on the top of ZnO NRs/ITO thin films by a two-stage spin coating method. The solar cell devices were characterized by using XRD, SEM-EDX, FTIR, UV-vis, and LCR meter. The results showed that ZnO NRs/ITO thin films were formed homogeneously and vertically oriented on all ITO substrates with hexagonal structures of zincite phases. When the growing time of ZnO NRs increased, the degree of homogeneity, density, and length of the rods enhanced as well. All the samples have the bandgap around 3.05 eV. The FTIR results showed the absorbent functional forces at 870 cm−1 and 1250 cm−1 related with H-C-N wavelengths, and ZnO wavelength ranges from 400 to 515 cm−1. The CH3NH3PbI3 perovskite solar cell device still contained PbI2 as impurities phase. The longer the growing time, the rods resulted by ZnO NRs had the wider diameter and the longer length and they were more homogenous. Meanwhile, the effect of the number of PbI2 impurities resulted in the higher dielectric and smaller current.

In this paper, the authors report the fabrication of Zn0.2Fe2.8O4 particles from Indonesian sand in the forms of nanopowder and magnetic fluid. The fabrication was conducted by employing a combined coprecipitation-sonochemical method. The analysis of the XRD data presented that the Zn0.2Fe2.8O4 was crystallized in a spinel structure with a lattice parameter of about 8.378 A. The data analysis of the TEM image showed the Zn0.2Fe2.8O4 particles distributed in nanometric size with a spherical shape. The magnetic investigation showed that the magnetic nanopowder and fluid both had superparamagnetic character. Moreover, the band gap of the Zn0.2Fe2.8O4 particles was about 2.28 eV. These characters open a significant opportunity for the prepared samples to be applied for sensory and antibacterial applications.

Titanium dioxide has been widely studied for its ability to photocatalytic and applications have high performance for photovoltaic applications. In this paper TiO2 nanoparticle was investigated for the degradation of methylene blue under UV light in various pH condition. The TiO2 nanoparticle was characterized by SEM and XRD. The results showed that TiO2 nanoparticle has the structure of anatase and have a particle size of 27 nm. The photocatalytic activity of TiO2 nanoparticle show that the degradation of methylene blue under UV light have dye removal of 97% dye was degraded in 3 h, but the degradation of methylene blue without UV light have dye removal of 15% dye was degraded in 3 h. It indicated that The photocatalytic activity of TiO2 nanoparticle could occur if there the UV light. If not UV light the photocatalytic activity cannot occurs, the degradation of Methylene Blue 15% is not a photocatalytic activity but it is adsorption of Methylene Blue by TiO2 nanoparticle. The photocatalytic activity of TiO2 nanoparticle has pH-sensitive. The photocatalytic activity of TiO2 nanoparticle in acid condition (pH 4.1) is 40%, in neutral condition (pH 7.0) is 90%, and in base condition (pH 9.7) is 97%. The highest photocatalytic activity occurs in base condition, it causes in base condition OH- can be direct reaction with a hole to produce hydroxyl radical (OH*).

Polyaniline (PANI), one of the conductive polymers has been intensively studied. The PANI has practically used in electronic device, and gas sensor. However, the PANI based on the electronic device has weaknesses such as fragile, and unstable of conductivity at high temperature and in an acidic environment. This obstacle can be solved by inducing other better thermal properties materials. One kind of the materials that meet the criteria is TiO2. However, TiO2 has limitation due to the low conductivity compared to the conductivity of PANI. Theoretically, this problem can be solved by reducing the particles size of TiO2 down to nanometric size. In this study, we prepared a composite film with a various amount of nano TiO2 to obtain information related the microstructure, electrical conductivity, and their thermal stability. The results of FTIR spectra analysis showed that the PANI-TiO2 composites films were successfully synthesized which is indicated by the appearance of PANI and TiO2 characteristic bonds associated with the references. XRD spectra showed the increased crystallinity of PANI-TiO2 composite films along the addition of TiO2. The SEM images presented the decreasing porosity of the samples by increasing the TiO2 contents. Further, the conductivity of PANI-TiO2 composite films decreased by increasing the TiO2 nanoparticles. On the other hands, the thermal stability of the PANI composite films increased by increasing the TiO2 nanoparticles.

One of the abundant natural resources along the coastal lines of Indonesia is silica sand. One of the beaches which has a lot of silica content is Bancar-Tuban beach. Silica can be used as a raw material of glass that has multiple properties in optic, dielectric, and other physical properties by introducing specific dopants. Some oxides have been used as dopant e.g. Al2O3, Fe3O4, and NiO. However, there has not been any comprehensive study discussing the multiple properties of natural silica-sand-based glass with Cr2O3 dopant so far. A series of samples have been prepared, which mean two solid steps to state melting technique. Cr2O3 was selected as a dopant due to its potential to control its color and to increase the dielectric constant of the glass. The synthesis of silica (SiO2) sand from BancarTuban beach was conducted through the sol-gel process. The composition varied as the addition of Cr2O3on 50SiO2-25B2O3-(6.5-x) Bi2O3-18.5Na2CO3-xCr2O3 (x = 0, 0.02, 0.04, 0.06 and 0.08mol), later called SBBN glass. The samples' characterizations of the structure and morphology were conducted through the use of XRD, and SEM-EDX. The measurements were done by using a DC capacitance meter in order to investigate the dielectric properties of the sample, under the influence of light. It is shown that addition of Cr2O3 did not alter the crystal structure but changed the structure of the functional bond formation. It is also revealed that the dielectric constant increased along with the increasing of Cr2O3. An interesting result was that the dielectric constant of the glass was quantized decreasingly as the increase of light.

Functionally glass materials have been widely applied in various technological applications remarkably due to their optoelectric properties. In this present study, the glass was prepared from leaching product of local silica sands. Bi2O3 and Na2CO3 were added to reduce the melting point of silica sand to form silica glass and Fe2O3/B2O3 was incorporated to examine its effect on the crystal structure, morphology, and light-induced dielectric properties of the borosilicate-based fuctional glass. The characterizations were conducted by means of Differential Thermal Analyses (DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and capacitance meter under the influence of light intensity. The XRD pattern shows the absence of any sharp diffraction peak indicates the amorphous state of the borosilicate glass. While the SEM image shows that the borosilicate glass exhibited amorphous characteristic. Furthermore, the increasing of Fe2O3 tends to reduce the dielectric constant. On the other hand, the increase of light intensity increase the dielectric constant with a step like properties.

The electrical properties of Cellulose Acetate (CA), especially extracted from water hyacinth, is rarely informed. CA is generally more stable compared to its cellulose. It has a good potential for electronic application with specific modifications such as inducing metal oxide. A combination of intrinsic properties of Zinc Oxide (ZnO) and CA is expected as a great potential for electrical and optical applications. CA-ZnO/ITO composite film was investigated in relation with its structure, dielectric constant, and the effect of light intensity on their dielectric constant. CA-ZnO composite films were prepared with different mass of ZnO i.e. 0; 0,02; 0,04; 0,06 and 0,08 grams. CA-ZnO solution was synthesized via the mixing method with PEG:DMF solvents by using a magnetic hotplate stirrer with the rotation rate of 1500 rpm at 80°C. The CA-ZnO solution was then deposited onto ITO/glass substrate by using spin coating technique. The CA-ZnO/ITO films were annealed at 160°C to remove the remaining solvents. The effects of ZnO composition on the structure (crystallinity and morphology) and dielectric constant properties were investigated by using X-Ray Diffractometer, Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, and LCR meter. It was shown that cellulose can be isolated from water hyacinth with the yield of 67,72 % by Chesson method and can further be transformed into CA. The X-ray diffraction pattern showed that there are 2 phases formed i.e. CA and ZnO. Furthermore, greater ZnO amount increased the crystallinity of composite films. The CA-ZnO films exhibit porous films with ZnO distributed on the CA surface films. Therefore, ZnO increases the dielectric constant of CA-ZnO composite films.