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Characterization of Electrode with Cu2O-ZnO/C and Pt-Ru/C Catalyst for Electrochemical Reduction CO2 to CH3OH Dea Radestia Rahmah; Dedi Rohendi; Nirwan Syarif; Addy Rachmat; Nyimas Febrika Sya'baniah; Dwi Hawa Yulianti
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 6, No 1 (2021): February 2021
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v6.i1.08

Abstract

Electrode characterization has been carried out with Cu2O-ZnO/C and Pt-Ru/C catalysts to convert carbon dioxide to methanol. Characterization are carried out with XRD analysis, Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The electrodes are made by distributing Cu2O-ZnO/C and/or Pt-Ru/C catalyst by spraying method. The results of XRD analysis showed that the characteristic peak of platinum was 2θ = 39.7⁰ - 40.74⁰ with an intensity of 970 cps and 1384 cps and the diffraction peak of Ru oxide was found at 47.02⁰ with an intensity of 923 cps. The peak of Cu2O characteristics appeared at 36.12⁰ with an intensity of 88 cps and the peak for ZnO characteristics at 68.2⁰ with an intensity of 13 cps. The test results with the cyclic voltammetry method showed that the electrode with a Cu2O-ZnO/C catalyst obtained the highest ECSA value which was 26.044 cm2/g, with an electrical conductivity value of 3.4 x 10-3 S/cm and a total real resistance of 5.9425 Ω .
The Light Transmittance and Electrical Conductivity Properties of Gelam Wood Carbon Nanosheet and Its Derivatives Nyimas Febrika Syabaniah; Nirwan Syarif; Dedi Rohendi; Mellysa Wandasari; Wara Dyahpita Rengga
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 4, No 3 (2019): October 2019
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v4.i3.126

Abstract

The research on the preparation and characterization of transparent electrode carbon nanosheet based gelam woods bark doped with SnO2-SbO2. XRD analysis showed peaks at 2θ = 26.87°; 26.38° for carbon crystal and at 2θ = 28.59°; 34.35° for SnO; at 2θ = 51.99°; 62.20° for SbO2. SEM analysis show that the carbons have self-curling sheets that indicated defection in their surface. The carbons have self-curling sheets, which indicated that their surfaces have many defects. It assumed when exfoliation process is undergone, the layers was significantly decreased as sonication process and formed rCNSO. Diffractogram XRD of CNS, CNSO and rCNSO showed diffraction peak at 2θ= 24.3°. Oxygen functional group in CNSO might cause an increasing of interlayers distance between hexagonal networks of carbon layer. It also affect electrical resistant or the conductivity. FTIR spectrum indicate that CNSO has several  absorption peaks at for –OH stretch for free water and alcohol. At 2337 cm-1 was showed a carboxylic acid peaks and C=C stretch at 1627 cm-1. There is a skeletal vibration rCNSO structure occurred at each graphene layers. The ratio of the integrated intensities (IG/ID = 0.89 for CNS, 0.85 for CNS-O, and 0.93 for rCNSO of Raman spectroscopy is significantly high. Electrical conductivity of transparent electrode ranges from 1.26 x 10-7 Scm-1 – 5.03 x 10-7Scm -1. The highest conductivity value on transparent electrode contained rCNSO.This result inferred that the usage of rCNSO can increase electrical conductivity. Therefore, the higher value of electrical conductivity can be related to the value of La. The average maximum absorption wavelength is observed at 350-530 nm which means that the transition of the electronic transition π→π* occurs in the conjugated carbons system. Electrical conductivity of transparent electrode ranges from 1.26 x 10-7 Scm-1 – 5.03 x 10-7 Scm -1. The highest conductivity value on transparent electrode contained rCNSO. The band gap values in the transparent electrode range from 2 eV - 3 eV which means they have conductor – semiconductor characters.Keywords: Nanosheet, Carbon, Electrical, Conductivity, Derivate.
Pelatihan Penggunaan Potentiostat sebagai Transfer Pengetahuan Ilmu Kimia untuk Guru – Guru SM Nirwan Syarif; Nyimas Febrika Sya’baniah
ABDINE: Jurnal Pengabdian Masyarakat Vol. 3 No. 1 (2023): ABDINE : Jurnal Pengabdian Masyarakat
Publisher : Sekolah Tinggi Teknologi Dumai

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.52072/abdine.v3i1.565

Abstract

Minimnya akses terhadap instrumentasi merupakan salah satu menyebabkan terhalangnya pengamatan terhadap suatu reaksi kimia.  Masalah tersebut utamanya disebabkan karena instrumen sulit didapatkan dengan alasan perlu sarana penunjang yang cukup besar, konsumsi listrik yang tinggi, perawatan khusus atau dana yang tidak sedikit. Kegiatan ini bertujuan untuk memberikan pemgetahuan tentang dasar – dasar elektrokimia dan praktikum elektrokimia dengan menggunakan potensiostat, spesifiknya “cheapstat” kepada guru IPA dan siswa di sekolah menengah, Metoda yang digunakan dalam pelaksanaan program pengabdian kepada masyarakat ini adalah presentasi dan pelatihan. Hasil evaluasi kegiatan menunjukkan bahwa praktikum yang diadakan cukup menarik untuk dilakukan baik untuk siswa dan guru. Sebanyak 50% dari partisipan setuju bahwa bahan dan alat yang digunakan dapat dikembangkan untuk praktikum. Sebagian lagi tidak setuju dikarenakan alat yang digunakan dirasakan masih cukup sulit diakses dengan berbagai alasan. Kegiatan ini dinilai positif oleh sebagian besar partisipan terbukti dengan nilai tengah dari keseluruhan pertanyaan survey sebesar > 3. Hal yang sama terlihat dari antusiasme partisipan yang tinggi, yaitu   dengan menggali ide-ide yang terkandung dalam kegiatan ini sehingga dapat dikembangkan untuk praktikum siswa.
The Electrochemical Conversion of CO2 into Methanol with KHCO3 Electrolyte Using Membrane Electrode Assembly (MEA) Dedi Rohendi; Nyimas Febrika Sya’baniah; Edy Herianto Majlan; Nirwan Syarif; Addy Rachmat; Dwi Hawa Yulianti; Icha Amelia; Dimas Ardiyanta; Isya Mahendra; Rr. Whiny Hardiyati Erliana
Science and Technology Indonesia Vol. 8 No. 4 (2023): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2023.8.4.632-639

Abstract

The electrochemical conversion process of CO2 into methanol using Membrane Electrode Assembly (MEA) has been done. The MEA consists of a Pt/C catalyst in the cathode and a Cu2O ZnO/C catalyst in the anode. The electrodes were made using the spraying method and then characterized using Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) methods to determine the ECSA (Electrochemical Surface Area) and electrical conductivity values. Besides that, also X-Ray Diffraction (XRD) and Scanning Electrode Microscopy – Energy Dispersive X-Ray (SEM-EDX) analysis was to determine the crystal and morphological structure. The voltammogram from CV analysis indicated that the ECSA value on the Pt/C electrode was 7.2 m2/g and the Cu2O-ZnO/C electrodes as 0.69 m2/g. The electrode’s electrical conductivity value with Pt/C catalyst was 1.15 x 10−3 S/cm, and the electrode with Cu2O-ZnO/C catalyst was 0.80 x 10−3 S/cm. The results of the XRD analysis confirmed the presence of Cu2O and ZnO on the Cu2O-ZnO/C electrode and Pt on the Pt/C electrode. Meanwhile, the results of the SEM-EDX analysis showed that the Pt/C catalyst was spread more evenly with a larger percentage than Cu2O and ZnO. The result of the conversion of CO2 to methanol was measured using a methanol analyzer with variations in KHCO3 electrolyte concentration, variation of temperature operation, and variation of time operation. The best methanol concentrations after distillation process were 79.06 w/v %, with 1 M KHCO3, at room temperature and 2 hours operation.
The Influence of Catalyst Loading on Electrocatalytic Activity and Hydrogen Production in PEM Water Electrolysis Rohendi, Dedi; Amelia, Icha; Sya'baniah, Nyimas Febrika; Yulianti, Dwi Hawa; Syarif, Nirwan; Rachmat, Addy; Fatmawati; Majlan, Edy Herianto
Science and Technology Indonesia Vol. 9 No. 3 (2024): July
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2024.9.3.556-564

Abstract

The climate change caused by the widespread and continuous use of fossil fuels is a problem that needs to be addressed urgently. One of the solutions offered is through an energy transition towards the use of new or renewable and low-carbon fuels. Hydrogen gas as a carrier of energy is an alternative solution that has attracted the attention of researchers, due to its high combustion energy and environmental friendliness. The production of hydrogen gas using the Proton Exchange Membrane Water Electrolysis (PEMWE) method is considered effective for large-scale production. This study investigates the impact of catalyst loading and various current densities on hydrogen production in the PEM water electrolysis process, utilizing the Cu2O/C catalyst. This study investigates the impact of catalyst loading and different current densities on hydrogen production in the PEM water electrolysis process, utilizing the Cu2O/C catalyst. The electrode catalytic properties were evaluated using the Cyclic Voltammetry (CV) method to determine the Electrochemical Surface Area (ECSA) and the Electrochemical Impedance Spectroscopy (EIS) method to determine the electrical conductivity. The ECSA and EIS measurements demonstrated that the best results were obtained at a higher catalyst loading of 2 mg/cm2 with an ECSA value of 0.21 m2/g and electrical conductivity of 3.04 × 10−6 S/cm. The production of hydrogen results showed that the highest hydrogen production rate was 3.75 mL/s with a catalyst loading of 2.5 mg/cm2, indicating that increasing the load could lead to a higher rate of hydrogen gas production, but this is highly dependent on the surface area utilized. Additionally, at higher current densities, the cell resistance in the electrolysis process may decrease, leading to reduced electrode efficiency for hydrogen production. Thus, the use of high currents may not always be advantageous in hydrogen production using the PEM water electrolysis method.
Hydrogen Production from Aluminum Waste Using the Aluminum-Water Method with Potassium as Activator Amelia, Icha; Rohendi, Dedi; Rachmat, Addy; Syarif, Nirwan; Yulianti, Dwi Hawa; Sya'baniah, Nyimas Febrika; Adhiyanti, Nurmalina; Adelia, Ory; Normah, Normah
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 9, No 2 (2024): June 2024
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v9.i2.111

Abstract

Research on hydrogen production from aluminum waste using the aluminum-water method using potassium as an activator has been successfully carried out. This research aims to determine the performance of the potassium activator in hydrogen production with variable water volume and potassium percentage. Hydrogen gas production is carried out using 60 mesh aluminum waste. Optimum conditions were achieved when a mass of 1 gram of aluminum was reacted with an additional volume of water of 1.5 mL, and 7% w/w of the activator mass, with the production of hydrogen gas of 553 mL at a production rate of 69 mL/minute.
Increasing Awareness of the Risks of Waste Cooking Oil (WCO) to Health and the Environment through Educational Training for the Community in Desa Sumber Rejo, Banyuasin Normah; Yulianti, Dwi Hawa; Sya'baniah, Nyimas Febrika; Adhiyanti, Nurmalina; Fazira, Yulin; Handani, Rika
Jurnal Abdimas Mandiri Vol. 9 No. 2
Publisher : UNIVERSITAS INDO GLOBAL MANDIRI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36982/jam.v9i2.5343

Abstract

The increasing consumption of cooking oil has led to a significant rise in waste cooking oil (WCO) production, posing serious health and environmental risks. Improper disposal of WCO contributes to water and soil pollution, while its repeated use in cooking has been linked to various health issues, including cardiovascular diseases and cancer. This community service programme aimed to raise awareness among housewives in Desa Sumber Rejo, Banyuasin, regarding the dangers of WCO through educational training. The study employed an interactive discussion approach, beginning with a questionnaire to assess participants' prior knowledge, followed by a socialisation session, and concluding with a post-test evaluation. The results revealed that approximately 80% of participants were unaware of WCO hazards before the training. However, post-training assessments showed a significant improvement in understanding, highlighting the effectiveness of targeted educational interventions. This programme underscores the importance of continuous awareness efforts and the promotion of sustainable WCO management practices, such as its potential repurposing into biodiesel or soap, to mitigate its negative impact on health and the environment.
Preparation of Palm Kernel Shell Binchotan for Radio Frequency Energy Harvesting Sya'baniah, Nyimas Febrika; Syarif, Nirwan; Rohendi, Dedi; Rachmat, Addy; Syahputra, Rio Aldo
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 10, No 3 (2025): October 2025
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Research on the development of radio frequency energy harvesting slabs from palm kernel shells binchotan has been done. The slabs were characterized by using XRD and FTIR intrumentations to determine their crystallography and functional groups. The electrical response of slabs was measured on impedance spectroscopy instrumentation. The conductivity, impedance, and dielectric constant were calculated from impedance spectroscopy data. Diffractograms showed crystalline carbon and confirmed with the existence of peaks, at 2θ, 24.5° and 44.56°. FTIR analysis showed that carbon palm shells have the absorption length is in the range of wave numbers 1100 – 1200 cm-1 for CO of carboxylic acid, aldehyde, ketone and ester, from 1475 to 1600 cm-1 for C=C aromatic ring and double peaks in 1900 – 2100 cm-1 for conjugated C-C. The slabs conductivity varies from 1 to 7 mScm-1. Impedance values for the slabs vary from 1.5 to 2.4 ohm. Dielectric constants for the slabs range from 0.42 to 140.
Effect of Hydrogen Flow Rate on MEA Performance with a Three-Catalyst-Layer Pt/C Configuration Yulianti, Dwi Hawa; Rohendi, Dedi; Budiman, Rahmadi; Firanda, Dera Okta; Rachmat, Addy; Sya'baniah, Nyimas Febrika
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 10, No 2 (2025): June 2025
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v10.i2.146

Abstract

An essential component in Proton Exchange Membrane Fuel Cells (PEMFCs) is the Membrane Electrode Assembly (MEA), which facilitates the electrochemical reaction between hydrogen and oxygen to generate electrical energy. This study examines the effect of varying hydrogen gas flow rates on the performance and durability of a Pt/C-based MEA. The MEA used in this research measures 6.5 cm × 30 cm with a catalyst loading of 2 mg/cm². The electrode is constructed in three layers of catalysts to maximize interfacial contact within the catalyst layer. The tested hydrogen flow rates were 100, 200, 300, and 400 mL/min. Performance evaluation was conducted through polarization (I–V) and power (I–P) curve measurements. The results indicated optimal performance at a 200 mL/min flow rate, with a maximum power density of 3.563 mW/cm² and a current density of 10.256 mA/cm². Durability testing was carried out under a constant current of 2 A for 12 hours and showed a voltage drop of 24.35% after 10 hours of operation. Electrochemical characterization using Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS), and Linear Sweep Voltammetry (LSV) yielded an Electrochemical Surface Area (ECSA) of 1.477 × 10⁻⁵ m²/g, electrical conductivity of 3.218 × 10⁻⁴ S/cm, and an electric charge of 4.2 × 10⁻⁶ C.