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Supercapacitor has received considerable attention as a promising energy storage device due to its fast charging, excellent cyclic stability, and high-power density. Activated carbon is the main material used to make supercapacitor electrodes because it has a high theory-specific surface area reach of 2,685 m2g−1 and low cost. However, structure micropore activated carbon had poor ionic diffusion and transportability that make inefficient surface area utilization, long charge-discharge performance, and low cycle life. Therefore, continuous research is needed to improve supercapacitor performance by adding and modifying structure micropores to increase the performance of electrochemically active sites so that ionic diffusion is better. This research is focused on the influence of concentration PVP immersion 0 M and 0.06 M with the dehydrogenation method. The higher concentration PVP strongly influenced the microstructure, morphology, and electrochemical process. The activated carbon mesoporous was characterized by XRD, SEM – EDX, FTIR, BET, and Charge Discharge. Further, the supercapacitor with the best performance is shown by the highest concentration of PVP 0.06 M exhibited the highest specific capacitance, energy density, and power density of 83.83 F.g−1, 60.06 Wh kg−1, 454.24 Wkg−1. ACM-0.06 had highest cycle stability in the cell voltage of 0-2.4 V at a current density of 0.1 Ag−1, and maximum energy density is 58.96 Wh kg−1 with 95.82 % capacity retention after 25 cycles. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) nanostructures are known to contribute a straight pathway for electron transfer to achieve good device performance. Besides that, Titanium dioxide (TiO2) is a metal oxide semiconductor, investigated as a material with upstanding physical and chemical properties with excellent light sensitivity, good relialibility in the environment, and low synthesis costs. In this research, the composite of ZnO nanorod/TiO2 designed to become a semiconductor coating material for photoanodes to support the process of electron transport. In this research, hexagonal structures of ZnO nanorods were synthesized by various growth time of hydrothermal synthesis method. The growth time affects to ZnO nanorods was systematically investigated on ZnO nanorods/TiO2 composites by scanning electron microscopy. From the XRD analysis showed that the ZnO nanorods in a crystalline phase in ZnO nanorods/TiO2 composites. Its crystallinity increases with increasing hydrothermal duration. In addition, the hydrothermal duration of 5 hours resulted the largest diameter and thickness of ZnO nanorod. [ABSTRACT FROM AUTHOR]

The design innovation and composition of TiO2 as a photoanode have been continuously studied in recent years to improve the photoconversion performance of Dye-sensitized Solar Cells (DSSC). The important components in the formation of TiO2 paste are solid content, solvents, and organic compounds as binders. In terms of solvents, water or simple alcohol are not suitable for screen printing methods, because cracking will occur after the annealing process by rapid evaporation. In this report, we investigated the addition of nitric acid (HNO3) and ethyl cellulose (CH2CH3) as a binder for optimize the overall DSSC performance. TiO2 photoanode was synthesized by screen printing method through the initial stage of making blocking layer with spin coating method. The effect of nitric acid and ethyl cellulose on, TiO2 powder was studied intensively to determine the best photoconversion performance. TiO2 films were prepared by varying the process without and with post-treatment. The XRD pattern confirmed the presence of a pure anatase phase of TiO2. The morphology of the photoanodes surface area were studied through SEM characterization. The characteristics of J-V shows an increasing in photocurrent and efficiency through the post-treatment process. DSSCs based on TiO2-HNO3 photoanode with post-treatment exhibited a highest efficiency of 3.59%. We found that the sample with post-treatment process have a smaller impedance than sample without post-treatment with charge transfer resistance (RCT) of 10 Ω and 23 Ω, respectively. It may indicate that the TiO2 film with post-treatment have a better interconnection then charge transfer and charge extraction process are more effective and resulting higher efficiency. [ABSTRACT FROM AUTHOR]