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Abstract Hot-carrier solar cells offer the potential for enhanced power conversion efficiency by tapping into the kinetic energy of hot carriers generated upon sunlight absorption. This involves using specially designed materials capable of efficiently extracting and utilizing the energy of these hot carriers to produce electrical power. Here, we observed such a hot carrier effect in hexamine doped methylammonium lead triiodide perovskite solar cells when exposed to 100 mW/cm2 of 5000 K white LED light. We discovered that these perovskite solar cells exhibited remarkable power conversion efficiency, reaching up to 54.22% with the Voc (open-circuit voltage) and Jsc (short-circuit current density) values were measured at 1.10 V and 54 mA/cm2, respectively. In comparison, under similar conditions but using a solar simulator, the power conversion efficiency remained below 20%. Our results suggest that the high PCE under white LED irradiation is due to the fine resonance between the light energy and perovskite band gap energy, enabling long carrier lifetime and then allowing massive photovoltaics process. These findings highlight the alternative to achieve hot carrier’s perovskite solar cells and efficient energy generation by converting light energy into the wavelength match with the perovskite materials absorber energy band gap.

With the use of several plasticizers (orange peel extract, chitosan, and sorbitol), rice straw cellulose has been used to synthesize and characterize bioplastics. This study aims to synthesize and characterize bioplastics from rice straw cellulose with various additions of plasticizers, namely orange-peel extract, chitosan, and sorbitol, each with a certain concentration so that quality improvement can occur. The methods used in this study include testing the tensile strength value, testing the percentage elongation, and testing the percentage of biodegradation. In addition, functional group characterization tests were also carried out using FTIR. The results obtained in this study were the best values for tensile strength and percentage elongation in treatment A, namely 10.2611 MPa and 13.88%. The percentage of biodegradation for 7 days reached 50.58%. Functional group absorptions were found in various plasticizers, namely C-H, O-H, C-O, C-N, and C=C. Based on existing data, bioplastics synthesized using rice straw cellulose in various plasticizers meet JIS (Japan Industrial Standards).

The experiments were carried out using Te-TiO2/Ti as working electrodes, prepared by the simple anodization technique and dip coating method, on Ti substrates (TiO2/Ti). The measurements were performed in an electrochemical cell using a three-electrode system, with Te-TiO2/Ti as the working electrode, Ag/AgCl as the reference electrode and pt as the auxiliary electrode. A flow system for determining the profile and photocurrent response of reactive orange 84 was developed using Linear Sweep Voltammetry (LSV) and Multi-Pulse Amperometry (MPA). The physicochemical properties of Te-TiO2/Ti electrodes have been studied using UV–vis DRS analysis techniques and compared with un-doped TiO2/Ti electrodes. The UV–vis DRS showed that the TiO2/Ti doped Te functionally decreases bandgap to 3.0 eV. The results showed that the photocurrent of reactive orange 84 was observed in the concentration range (1-5 μM), with a linear response between concentration and charge.

Husoak Village, Hubikiak District Jayawijaya is one of the regions in Papua province where plants including chili. The cultivation system are extensively and using traditional method depending on soil nutrients. The aim of the research is to see how utilizing a mix of organic fertilizer and mulch affects the growth and development of chili plants. This research was conducted based on a randomized block design consisting of 4 treatments. namely P1 = compost; P2 = compost + liquid organic fertilizer + plastic mulch; P3 = compost +TiO2+liquid organic fertilizer + plastic mulch; P4= Control (No Treatment). When compared to the control. the results showed that using a mix of organic fertilizer (compost and liquid organic) and mulch had an effect that was not significant. This demonstrates that cayenne pepper plants may still get the nutrients they require from nutrients available in the soil. Fertile land is still classified as cultivated land.

The manufacture of titanium dioxide (TiO2) electrodes is made by anodizing method and coated with ilmenite (FeTiO3) through a dip-coating technique. The ilmenite (FeTiO3) coated TiO2/Ti plate electrode was developed for the degradation of the reactive blue 160 dye under photoelectrocatalytic UV and Visible light irradiation. The performance of FeTiO3-TiO2 / Ti composites degrades reactive blue 160 under UV irradiation and is visible photoelectrocatalytically compared to TiO2. The results of XRD characterization of TiO2 crystals in the form of anatase at 2θ, namely 35.1 ° (110), and the substitution of Fe dopant on TiO2 in the form of anatase and rutile crystals. FTIR data indicated the presence of Fe-O bonds at wave numbers

Abstract Research on the transformation of Oil Palm Empty Fruit Bunches (OPEFB) through pretreatment process using ionic liquid triethylammonium hydrogen sulphate (IL [TEA][HSO4]) was completed. The stages of the transformation process carried out were the synthesis of IL with the one-spot method, optimization of IL composition and pretreatment temperature, and IL recovery. The success of the IL synthesis stage was analyzed by FTIR, H-NMR and TGA. Based on the results obtained, it showed that IL [TEA][HSO4] was successfully synthesized. This was indicated by the presence of IR absorption at 1/λ = 2814.97 cm−1, 1401.07 cm−1, 1233.30 cm−1 and 847.92 cm−1 which were functional groups for NH, CH3, CN and SO2, respectively. These results were supported by H-NMR data at δ (ppm) = 1.217–1.236 (N–CH2–CH3), 3.005–3.023 (–H), 3.427–3.445 (N–H+) and 3.867 (N+H3). The TGA results showed that the melting point and decomposition temperature of the IL were 49 °C and 274.3 °C, respectively. Based on pretreatment optimization, it showed that the best IL composition for cellulose production was 85 wt%. Meanwhile, temperature optimization showed that the best temperature was 120 °C. In these two optimum conditions, the cellulose content was obtained at 45.84 wt%. Testing of IL [TEA][HSO4] recovery performance for reuse has shown promising results. During the pretreatment process, IL [TEA][HSO4] recovery effectively increased the cellulose content of OPEFB to 29.13 wt% and decreased the lignin content to 32.57%. The success of the recovery process is indicated by the increasing density properties of IL [TEA][HSO4]. This increase occurs when using a temperature of 80–100 °C. The overall conditions obtained from this work suggest that IL [TEA][HSO4] was effective during the transformation process of OPEFB into cellulose. This shows the potential of IL [TEA][HSO4] in the future in the renewable energy sector.

A rapid and facile method for detecting profenofos is crucial for environmental surveillance and ensuring product quality. Electrochemical sensing, as appears presents significant potential as a nascent technology for profenofos detection in recent years. Herein, NiO-CuO bimetallic modified graphene paste electrode/TiO2 was developed for the detection of profenofos over cyclic voltammetry technique. The TiO2@NiO-CuO were synthesized through the sol-gel method and characterized by various analyses such as SEM, XRD, and FTIR and electrochemical techniques. The superior electrochemical properties of the suggested GPE/TiO2@NiO-CuO were demonstrated by cyclic voltammetry investigations performed in Fe(CN)64-/3- solution. The electrode performance of GPE/TiO2 doped with NiO-CuO towards K3FeCN6 solution is notably enhanced compared to GPE/TiO2 undoped. Doping notably increased the conductivity of the GPE/TiO2, leading to a performance enhancement in the electrocatalytic activity and detection sensitivity of profenofos. Under optimum conditions, the GPE/TiO2@NiO-CuO demonstrated an impressively low detection limit of 0.00132 µg/L, coupled with a favorable detection range spanning from 1.0 μg/L to 10 μg/L with correlation coefficient R² = 0.992. Moreover, the electrode demonstrates remarkably very good stability, and repeatability with %RSD is only 0.94% over 11 repeated measurements. These results signify that GPE/TiO2@NiO-CuO for detecting profenofos, demonstrates exceptional excellent linearity, repeatability, and promising sensitivity for pesticide detection. [ABSTRACT FROM AUTHOR]

The new composite material Al(III)-TiO2 has been synthesized and applied as a modifier of graphene paste electrode for the determination of fipronil pesticide by cyclic voltammetry. The methods were to synthesis of Aluminum-Titanium dioxide (AT), preparation of graphene paste electrode with mass varied Al(III)-TiO2 (GAT) (0.05 g, 0.1 g, 0.2 g), and fipronil electroanalytic respons. Addition of Al(III)-TiO2 to the graphene paste electrode shows redox properties which are well characterized by a fast electron transfer process. Based on the results of measurements in a solution containing fipronil, it is known that fipronil is oxidized at a potential value of 0.26 V. Furthermore, the fipronil oxidation process on the GAT surface is influenced by diffusion control, this is powered by R2 value 0.91 when plotted between peak oxidation currents (Ip­a) vs. root scan rate. Other results show that measurement linearity is in the range 0.01 to 0.09 µg/L with a limit of detection (LOD) value of 0.0164 μg/L. Moreover, GAT shows good stability in the determination of fipronil with% RSD equal to 5%.

This research explores the heightened sensitivity of the electrochemical formaldehyde detection achieved by incorporating a modified graphene paste electrode with a titanium dioxide-silver (TiO2/Ag) composite (GTA). The G-TiO2 matrix was augmented with varying masses of silver modifiers, namely, 0.2, 0.4, 0.6, and 0.8 g, aiming to establish the most effective composition for formaldehyde detection. Characterization through scanning electron microscopy and energy-dispersive X-ray spectroscopy confirmed the material's composition, revealing GTA electrode nanocomposites consisting of carbon, oxygen, titanium, and silver with the compositions of 77.05, 19.46, 2.39, and 1.11%, respectively. An electrochemical analysis was conducted to assess the efficacy of the developed electrode in a 1 M K3[Fe(CN)6] solution. Furthermore, a real sample testing was performed to evaluate the practical utility of the electrode gauging its efficiency through the calculation of percentage recovery before and after treatment. The GTA electrode with a 0.4 g Ag modifier exhibited the optimal performance, as evidenced by a Horwitz Ratio stability test result of 1.38% and a limit of detection of 0.0168 µg/L. This research highlights the promising potential of the GTA electrode for the precise and sensitive formaldehyde detection, particularly in processed food products. [ABSTRACT FROM AUTHOR]

Jalur sinyal protein kinase Ras-Raf-MEK-ERK adalah salah satu target penting dalam penemuan obat antikanker. Senyawa turunan benzamida diketahui berpotensi sebagai inhibitor alosterik Mitogen Enhanced Kinase (MEK). Pada penelitian ini dilakukan studi hubungan kuantitatif stuktur dan aktivitas (HKSA) dan penambatan molekul pada 30 senyawa turunan benzamida sebagai inhibitor alosterik MEK untuk mendapatkan senyawa baru turunan benzamida yang lebih poten sebagai inhibitor alosterik MEK. Perhitungan 13 deskriptor molekul yang mewakili parameter sterik, hidrofobik dan elektronik dilakukan dengan perangkat lunak MOE 2009.10, sedangkan analisis regresi multi linear dengan SPSS 19.0 digunakan untuk mencari hubungan antara variabel bebas (deksriptor molekul) dengan variabel terikat (aktivitas penghambatan senyawa pada MEK). Model HKSA terbaik yang diperoleh adalah pIC50 = 14.229 – 0.00001(AM1_E) + 0.043(ASA_H) + 33.609(Glob) – 0.648(Log S) – 0.047(Vol) dengan kriteria statistik R=0.965; R2=0.931; Fhitung/ Ftabel= 17.693, dan q2 = 0.8897. Desain senyawa baru dilakukan menggunakan model HKSA tervalidasi dan diperoleh 2 senyawa baru turunan benzamida, C1, dan C2, yang memiliki aktivitas lebih baik dari senyawa induk. Studi penambatan molekul menunjukkan bahwa kedua senyawa baru tersebut mampu berinteraksi pada sisi alosterik protein MEK melalui ikatan hidrogen dan ikatan van der Waals dengan residu-residu asam amino krusial protein MEK. Penelitian ini mengindikasikan bahwa kedua senyawa baru yang didesain dapat ditindaklanjuti pada studi penemuan obat yang menargetkan MEK pada sisi alosterik. DOI:http://dx.doi.org/10.15408/jkv.v4i1.7454