Characteristic of microstructure and magnetic properties in LaFeO3 using co-precipitation method

Abstrak. Perkembangan penelitian material ferit memiliki karakteristik mikrostruktur dan sifat magnetik yang berbeda-beda. Karakteristik mikrostruktur dan sifat magnetik dari Fe3O4 dan LaFeO3 telah berhasil dilakukan menggunakan metode ko-presipitasi lanthanum klorida dan pasir besi alam digunakan sebagai prekursor untuk preparasi sintesis nanopartikel Fe3O4 LaFeO3. Rasio molar antara lanthanum klorida dan pasir besi alam adalah 1:1, dan tanpa lanthanium. Karakterisasi sampel menggunakan XRD, SEM dan VSM. Hasil XRD menunjukkan bahwa kedua sampel telah memiliki fase tunggal tanpa pengotor kristal seperti La2O3 atau Fe2O3. Hasil morfologi SEM menunjukkan bahwa Fe3O4 dan LaFeO3 memiliki ukuran partikel yang random. Histogram distribusi sebaran partikel untuk kedua sampel ini menunjukkan range 50-300 nm. Sifat magnetik dari sampel Fe3O4 memiliki Ms= 20 emu/g, Mr= 9 emu/g dan H= 400 Oe, sedangkan sifat magnetik LaFeO3 yaitu Ms= 10 emu/g, Mr= 8 emu/g dan H= 410 Oe. Hasil mikrostruktur dan sifat magnetik dalam penelitian ini dapat mendukung dalam pembuatan magnet permanen.  Abstract. The development of research on ferrite materials has different microstructural characteristics and magnetic properties. The microstructural characteristics and properties of Fe3O4 and LaFeO3 have been successfully carried out using the co-precipitation method. Lanthanum chloride and natural iron sand were used as precursors for the preparation of the synthesis of Fe3O4 LaFeO3 nanoparticles. The molar ratio between lanthanum chloride and natural iron sand is 1:1, and without lanthanium. Sample characterization using XRD, SEM and VSM. The XRD results show that the second sample already has a single phase without crystal impurities such as La2O3 or Fe2O3. SEM morphology results show that Fe3O4 and LaFeO3 have random particle sizes. Histograms of particle distribution distribution for these two samples show the range of 50-300 nm. The nature of the sample Fe3O4 has Ms= 20 emu/g, Mr= 9 emu/g and H= 400 Oe, while the specific properties of LaFeO3 are Ms= 10 emu/g, Mr= 8 emu/g and H= 410 Oe. The results of the microstructure and magnetic properties in this study can support the manufacture of permanent magnet

Study and characterization of Fe3O4 synthesized from natural iron sand in Sumatera Utara

Abstrak. Pasir besi alam adalah satu dari sumberdaya alam di Indonesia, khususnya Sumatera Utara, yang pemanfaatannya belum dilakukan secara optimal. Penelitian ini dilakukan untuk menganalisis kandungan dan ukuran butir Fe yang terdapat di Provinsi Sumatera Utara. Pembuatan sampel pasir besi alam ini menggunakan metode milling basah yang dikeringkan pada suhu 100oC hingga sampel menjadi serbuk. Selanjutnya, proses ekstrasi menggunakan magnet permanen dilakukan pada sampel pasir untuk memisahkan material magnetik dan non magnetik didalamnya. Sampel magnetik yang diperoleh kemudian diuji menggukan alat XRD, SEM-EDX dan VSM. Hasil XRD menunjukkan bahwa sampel pasir besi alam memiliki fasa tunggal yaitu fasa magnetite (Fe3O4), dan struktur kristal kubik spinel yang mana a = b = c = 8.513 Ǻ. Berdasarkan hasil SEM-EDX, terdapat kandungan unsur Fe dan O didalam pasir besi, yang berasal dari fase Magnetit (Fe3O4), maghemite (γ-Fe2O3) dan hematit (α-Fe2O3). Hasil VSM menunjukkan bahwa parameter sifat magnetik saturasi (Ms) sebesar 30.52 emu.g-1, magnetik remanansi (Mr) sebesar 21.66 emu.g-1 dan koersivitas sebesar 455.17 Oe. Hasil studi ini berpotensi dalam pengolahan material magnetik lainnya sehingga dapat ditindaklanjuti dalam pembuatan material berikutnya dalam aplikasi bidang tertentu. Abstract. Natural iron sand includes one of the natural resources in Indonesia, especially in Sumatera Utara which has not been used optimally. The study was done to investigate the content and grain size of Fe found in Sumatera Utara. The manufacture of this natural iron sand sample uses the wet milling method which is dried at 100oC until the sample becomes powder. Next, the extraction process using permanent magnet was performed on the sand sample to separate its magnetic and non-magnetic materials. The iron sand was tested via XRD, SEM-EDX and VSM. The XRD results reveal that the natural iron sand sample has a single phase of magnetite (Fe3O4) phase, and a spinel cubic crystal structure with a = b = c = 8.513 Ǻ. SEM-EDX results show that the iron sand sample consists of Fe and O components, which come from Magnetite (Fe3O4), Maghemite (γ-Fe2O3) and hematite (α-Fe2O3) phases. The VSM results show that the saturation type (Ms) parameter is 30.52 emu.g-1, remanence type (Mr) is 21.66 emu.g-1 and coercivity is 455.17 Oe. The study’s results are potential in other making magnetic materials, so that they can be followed up in the manufacture of subsequent materials in certain applications, respectively

Preparation and characterization of ZnFe2O4 on the microstructures and magnetic properties

Abstrak. Telah berhasil dilakukan sintesis ZnFe2O4 menggunakan metode sol-gel. ZnO dan serbuk Fe3O4 dicampur dan dipanaskan menggunakan hotplate pada suhu 60oC selama satu jam. Efek dari doping ZnO pada mikrostruktur, morfologi dan sifat magnet dikarakterisasi menggunakan XRD, SEM dan VSM. Hasil dari XRD dan SEM mengkonfirmasi bahwa struktur ZnFe2O4 spinel ferit menunjukkan kristal rata-rata 1 μm. Kemudian sifat kemagnetan ZnFe2O4 yang dikonfirmasi bersifat paramagnetik dengan kondisi optimum dari sifat kemagnetan tersebut tercantum sebagai berikut: Ms 0.4 emu×g-1, Mr 0.2 emu×g-1, dan Hc 230 Oe.Abstract. ZnFe2O4 have been synthesized using sol-gel method. ZnO, and Fe3O4 powder was mixing with hotplate for one hour in 60oC. Effect of ZnO doped on microstructure, morphology and magnetic properties were investigated using XRD, SEM and VSM. The result of XRD and SEM confirmed that the ZnFe2O4 structure of spinel ferrite has average crystal of 1 μm. The magnetic properties of ZnFe2O4 confirmed paramagnetic with the optimum condition of the magnetic properties are listed in the following: Ms 0.4 emu×g-1, Mr 0.2 emu×g-1, and Hc 230 Oe.Keywords: ZnFe2O4, Sol-gel method, Microstructures, Magnetic Properties

Synthesis of magnetic activated carbon-supported cobalt(II) chloride derived from pecan shell (Aleurites moluccana) with co-precipitation method as the electrode in supercapacitors

The synthesis of materials on magnetic activated carbon is of concern, with a simple and environmentally friendly. The research used pecan shell (Aleurites moluccana) as a carbon source. The breakthrough made in this research is to make magnetic activated carbon electrodes in supercapacitors. Obtained on the XRD diffractograms show the graphite lattice, respectively. Also, a sharp, narrow peak is seen at 2θ = 26° in the carbon samples spectrum, showing a highly graphitized fraction. FESEM-EDX showed AC20/80 that the shape of the particles was like plates indicating that the particles had been formed. AC80/20 is the surface morphology in which particles with irregular shapes indicate that particles have been formed, where the shape of the particles is irregular. The composition between C and O is also balanced. AC80/20 has lower Co content than AC20/80, AC40/60, AC60/40, and AC50/50 and it appears that AC80/20 is better than the others. The magnitude of the coercivity states that AC20/80, AC80/20, AC40/60, AC60/40, and AC50/50 are strong magnets. The lower the value of the open circuit potential, it will show electrochemical stability. The Nyquist plots of magnetic activated carbon show a straight vertical indicating the process of charge transfer resistance at the low electrode. Obtained specific capacitance AC80/20 at 150F/g

The effectiveness of activated carbon from nutmeg shell in reducing ammonia (NH3) levels in fish pond water

Ammonia (NH3) is one of the compounds found in water, and when it exceeds the threshold, it can become toxic, posing a problem for fish farmers. This research aims to reduce the ammonia (NH3) levels using activated carbon adsorbents based on nutmeg shell. The activated carbon was produced using a 1 M HCl solution as an activator with temperature variations of 600 °C, 650 °C, and 700 °C. The activated carbon obtained complies with the SNI No.06–3730–1995 standard, with characteristics of 9.23 % moisture content, 8.45 % volatile matter content, 9.71 % ash content, and 81.84 % bound carbon content. The best sample was obtained with an adsorbent mass of 6 g at 700 °C, reducing Ammonia (NH3) by 90 % with an adsorption capacity of 0.03 mg/g. Subsequently, the sample was subjected to Fourier Transform Infrared (FTIR), X-ray diffraction (XRD), and Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) analysis. Functional carbon groups were identified, especially at wavenumbers 3745.22 cm−1 and 3621.27 cm−1, facilitating adsorption. The sample had an amorphous structure but contained crystalline carbon structures. The highest peak observed was at 29.57° with a miller index (201). The surface of the sample exhibited pores, predominantly composed of carbon and oxygen. The adsorption mechanism of ammonia (NH3) on activated carbon occurs through intermolecular interactions. This research demonstrates the potential of a newly developed material for reducing NH3

Influences of Co compositions in CoFe2O4 on microstructures, thermal, and magnetic properties

In this research, the influence of cobalt compositions in CoFe2O4 using co-precipitation method in low calcination temperature of 200 °C has been obtained. Microstructures, thermal and magnetic properties were analyzed starting Thermogravimetric Analysis /Differential Scanning Calorimetry (TGA /DSC), X-ray Diffraction (XRD), Field Emission - Scanning Electron Microscope (FE-SEM). Vibrating Sample Magnetometer (VSM) used for analyzing magnetic properties of CoFe2O4. The reductions of mass change are in the range of 7.62 % at 95 °C–300 °C and endothermic process at 800 °C. Microstructures from XRD results confirmed that influences of cobalt in CoFe2O4 affect the CoFe2O4 crystal and its peak decreases as Co compositions increases. Then FE-SEM EDS confirmed spinel ferrite structure in Sample 1, Sample 2 and Sample 3, while the distribution of particle size on histograms confirmed that Sample 1, 2 and 3 are around 55.6 nm, 45.3 nm and 39.6 nm consecutively. The results from FE-SEM measurement showed that the increases of Co compositions decreased the particle size. Also seen from FE-SEM results that with low calcination temperatures resulting the spinel ferrite. Then, the optimum of the conditions magnetic properties was observed for Sample 3 with Ms = 21.74 emu.g-1, Mr = 2.37 emu.g-1, Hc = 556.572 Oe respectively

Activated carbon from biomass waste candlenut shells (Aleurites moluccana) doped ZIF-67/Fe3O4 as advanced materials for supercapacitor

Biomass waste candlenut shells, such as adsorbent carbon, can be utilized. Fe3O4 has great electrical conductivity, and ZIF-67 has diverse pores. Activated carbon, Fe3O4, and ZIF-67 were prepared to obtain a combination of these materials using the co-precipitation method. FTIR spectra show a peak at 1341 cm−1, which depicts the Fe-O bending vibration. At peak 1558 cm−1 shows C = N streching. The top of 1412 cm−1 and 991 cm−1 extend the full ring. The sp2 aromatic peak may be seen at 1150 cm-1C-H bond. The surface area is 17.76 m2/g, and the pore size is 14.99 nm. Coercivity is 119.63 Oe, which shows a strong magnet. The highlight of the study was activated carbon from biomass waste candlenut shells (Aleurites moluccana) doped ZIF-67 supported Fe3O4 with specific capacitance shows high. The diffusion percentage shows fewer electrolyte ions entering the active material, and resistance also showed low results. It can increase the percentage of capacitive ions, thus improving the electrode. Electrochemical results show 1335F/g of high specific capacity at 1 A/g current density. It indicates a suitable candidate material for supercapacitor electrodes

Sweet potato‑derived carbon nanosheets incorporate NiCo2O4 nanocomposite as electrode materials for supercapacitors

Since a composite electrode made of carbon and transition metal oxides has much potential to be the best electrode type for a future energy storage system, the low-temperature solution growth method was used to make a carbon framework from sweet potato with NiCo2O4 nanoparticles attached to it. This method is easy, cheap, and can be used for large-scale commercial production. FTIR spectra a peak band of Ni-O and Co-O and the bending functional group at wave number 857 cm−1. XRD shows the crystal planes (111), (220), (331), (222), (400), (422), (511), and (440) at 2θ = 18.97°, 31.97°, 37.51°, 38.10°, 44.55°, 55.51°, 58.65°, and 64.92°, which indicates the NiCo2O4. The typical broad peaks around 23.3° can be linked to (002) lattice planes of amorphous carbon. The average size of the grains in the NiCo2O4/C samples was found to be 21.5 ± 0.5 nm. VSM shows that NiCo2O4/C has strong magnet properties. Based on the CV curve formed, it can be seen that NiCo2O4/C-2.8 has a balanced cathodic and anodic curve and also a higher current density than the others. It shows that NiCo2O4/C-2.8 has a higher ability to move electrons. The addition of the number of variations in the carbon mixture in NiCo2O4 shows the specific capacitance. It shows that carbon can prevent the movement of electrons in NiCo2O4, causing a decrease in performance. The right amount of carbon can increase the electron transfer ability

Solvothermal synthesized N–S doped carbon dots derived from cavendish banana peel (Musa paradisiaca) for detection of Fe(III) and Pb(II)

The synthesis of NS-CDs was carried out using precursors from Cavendish Banana Peel and l-Cysteine as a dopant with the solvothermal method. The characteristics of NS-CDs were analyzed through High-resolution transmission electron microscopy (HR-TEM), X-ray diffractometer (XRD), energy dispersive X-Ray spectroscopy (EDX), X-Ray Fluorescence spectrometer (XRF), X-Ray photoelectron spectroscopy (XPS), UV–Visible spectrophotometer, Photoluminescence, and Atomic Absorption Spectroscopy (AAS). Based on HR-TEM analysis, NS-CDs exhibited a spherical shape (dot) with an average particle size of 2.03 nm. Meanwhile, based on XRD characterization, NS-CDs showed a graphite carbon shape according to the diffraction patterns (002) and (001). Subsequently, XRF and EDX testing revealed that the elemental composition was dominated by carbon (C), nitrogen (N), Sulphur (S), and oxygen (O). Furthermore, in XPS testing, S2p, C1s, N1s, and O1s peaks correlated around 64 eV, 285 eV, 400 eV, and 531 eV respectively. In UV–Vis testing, the energy gap was found to be 5.71 eV (NS-CDs 3:1), 5.46 eV (NS-CDs 3:1), 5.25 eV (NS-CDs 1:1), 5.51 eV (NS-CDs 1:2), and 5.56 eV (NS-CDs 1:3). Characterization of PL for NS-CDs 3:1, 2:1, 1:1, 1:2, 1:3 showed peak excitation at 403 nm and emission at 493.39 nm, 493.65 nm, 494.98 nm, 496.04 nm, and 497.11 nm, respectively. During heavy metal ion detection testing, Fe(III) and Pb(II) using AAS instruments, it was found that the NS-CDs 1:3 sample yielded the best results with an Adsorption capacity worth 21.35 mg/L and Removal Efficiency worth 85.40 %. These results clearly indicate that NS-CDs material can be used as an ideal heavy metal detection material, especially in wastewater