The molten salt synthesis of ABi2Ta2O9 (A = Ca, Sr, Ba) as photocatalyst material

The two-layer member of Aurivillius compound ABi2Ta2O9 (A= Ca, Sr, Ba) has been reported can be applied as photocatalyst material. In this research, the compound ABi2Ta2O9 (A= Ca, Sr, Ba) was synthesized using the molten salt method and measured photocatalytic act ivity to degrade methylene blue. Difractogram samples showed that the compound ABi2Ta2O9 (A= Ca, Sr, Ba) was successfully obtained but st ill found impurit ies on the samples. Micrograph samples showed that the particle morphology of ABi2Ta2O9 (A= Ca, Sr, Ba) was plate-like and found agglomerat ion in all part icles. The calculat ion using the Kubelka-Munk equat ion exhibited that CaBi2Ta2O9, SrBi2Ta2O9, BaBi2Ta2O9 sequent ially have bandgap energy of 3.51, 3.21, and 2.44 eV. The degradat ion test results of methylene blue solut ion show that CaBi2Ta2O9, SrBi2Ta2O9, and BaBi2Ta2O9 materials can degrade sequent ially by 14.44, 24.23, and 15.99 % for 80 minute

Uji Degradasi Pewarna Rhodamine B oleh Senyawa Aurivillius Lapis Dua SrBi2Ta2O9

Senyawa Aurivillius lapis dua SrBi2Ta2O9 dilaporkan berpotensi sebagai material fotokatalis sehingga dapat digunakan untuk mendegradasi limbah zat warna. Pada penelitian ini telah disintesis senyawa SrBi2Ta2O9 dengan metode reaksi keadaan padatan dan selanjutnya dilakukan uji kemampuan dalam mendegradasi zat warna rhodamine B. Difraktogram menunjukkan bahwa, telah terbentuk senyawa SrBi2Ta2O9 dengan grup ruang A21am dan tidak ditemukan adanya pengotor. Gambar scanning electron microscopy (SEM) menunjukkan bahwa partikel SrBi2Ta2O9 berbentuk plate-like dan teraglomerasi. Spektrum diffuse reflectance spectroscopy menunjukkan bahwa SrBi2Ta2O9 mempunyai energi celah pita sebesar 3,15 eV (~393,60 nm). Hasil uji degradasi larutan rhodamine B menunjukkan bahwa kemampuan SrBi2Ta2O9 dalam mendegradasi adalah 8,6% selama 80 menit. Kemampuan degradasi yang rendah dikarenakan ukuran partikel SrBi2Ta2O9 relatif besar dan dalam keadaan teraglomerasi

Photocatalytic Degradation of Rhodamine B by Two-Layer Aurivillius Compound SrBi2Ta2O9

Senyawa Aurivillius lapis dua SrBi2Ta2O9 dilaporkan berpotensi sebagai material fotokatalis sehingga dapat digunakan untuk mendegradasi limbah zat warna. Pada penelitian ini telah disintesis senyawa SrBi2Ta2O9 dengan metode reaksi keadaan padatan dan selanjutnya dilakukan uji kemampuan dalam mendegradasi zat warna rhodamine B. Difraktogram menunjukkan bahwa, telah terbentuk senyawa SrBi2Ta2O9 dengan grup ruang A21am dan tidak ditemukan adanya pengotor. Gambar scanning electron microscopy (SEM) menunjukkan bahwa partikel SrBi2Ta2O9 berbentuk plate-like dan teraglomerasi. Spektrum diffuse reflectance spectroscopy menunjukkan bahwa SrBi2Ta2O9 mempunyai energi celah pita sebesar 3,15 eV (~393,60 nm). Hasil uji degradasi larutan rhodamine B menunjukkan bahwa kemampuan SrBi2Ta2O9 dalam mendegradasi adalah 8,6% selama 80 menit. Kemampuan degradasi yang rendah dikarenakan ukuran partikel SrBi2Ta2O9 relatif besar dan dalam keadaan teraglomerasi.   Kata kunci: aglomerasi, fotokatalis, rhodamine B, SrBi2Ta2O9, ukuran partikel.The two-layer Aurivillius compound SrBi2Ta2O9 has been known as a potential photocatalyst as results can be applied to degrade dye waste. In this research, the SrBi2Ta2O9 compound was synthesized using a solid-state reaction and then measured to degrade rhodamine B dye. The diffractogram showed that the SrBi2Ta2O9 compound has formed with space group A21am and there are no impurities. Scanning electron microscopy (SEM) image showed that the shape of SrBi2Ta2O9 particles is plate-like and in agglomeration condition. DRS spectrum showed that the bandgap energy of SrBi2Ta2O9 is 3.15 eV (~ 393.60 nm). The rhodamine B solution's degradation test results showed that the sample could degrade 8.6% rhodamine B for 80 minutes. The low degradability is due to the particles. SrBi2Ta2O9 has a bigger size and also were found agglomeration.   Keywords: agglomeration, particle size, photocatalyst, rhodamine B, SrBi2Ta2O9

Synthesis and characterization of Fe-doped CaTiO3 Polyhedra prepared by molten NaCl Salt

CaTiO3 as one of the perovskite-based photocatalysts has a band gap energy of 3.5 eV (�354 nm), thus will work at the ultraviolet light region. One of the strategies to decrease the band gap energy is doping metal. In this research, CaTiO3 was doped by Fe element as purposes to decreasing its band gap energy. Fe doped CaTiO3 with different Fe concentrations (0, 5, 10, 15, and 20%) compounds were synthesized using molten NaCl salt method. The diffractogram samples showed that the Fe-doped CaTiO3 crystal was successfully prepared. The refinement results showed that the samples have space group Pbnm a with Rp and Rwp values below 12%. The SEM images showed that the particle shape was regular polyhedra morphology, and doping Fe3¸ caused the particle size to decrease and agglomerate. The UV-Vis DRS spectra showed that the Fe-dopant revealed the absorption light at visible range wavelength by meaning that Fe-dopant successfully lowered the band gap value of CTO (3.43 eV

Synthesis and characterization of Fe-doped CaTiO3 Polyhedra prepared by molten NaCl Salt

CaTiO3 as one of the perovskite-based photocatalysts has a band gap energy of 3.5 eV (�354 nm), thus will work at the ultraviolet light region. One of the strategies to decrease the band gap energy is doping metal. In this research, CaTiO3 was doped by Fe element as purposes to decreasing its band gap energy. Fe doped CaTiO3 with different Fe concentrations (0, 5, 10, 15, and 20%) compounds were synthesized using molten NaCl salt method. The diffractogram samples showed that the Fe-doped CaTiO3 crystal was successfully prepared. The refinement results showed that the samples have space group Pbnm a with Rp and Rwp values below 12%. The SEM images showed that the particle shape was regular polyhedra morphology, and doping Fe3¸ caused the particle size to decrease and agglomerate. The UV-Vis DRS spectra showed that the Fe-dopant revealed the absorption light at visible range wavelength by meaning that Fe-dopant successfully lowered the band gap value of CTO (3.43 eV

Sintesis dan karakterisasi material fotokatalis heterojunction BI4TI3O12/SrTiO3 dengan metode sonikasi

Bi4Ti3O12 dan SrTiO3 merupakan material semikonduktor yang berpeluang untuk digunakan sebagai fotokatalis. Namun, kedua material tersebut memiliki kekurangan karena hanya mampu bekerja pada daerah sinar UV dan memiliki laju rekombinasi yang cepat. Pembuatan material heterojunction merupakan salah satu upaya untuk mengatasi masalah ini. Riset ini bertujuan untuk mempelajari sifat fotokatalitik komposit Bi4Ti3O12/SrTiO3 yang disintesis dengan metode sonikasi. Hasil penelitian menunjukkan bahwa Bi4Ti3O12/SrTiO3 berhasil disintesis tanpa adanya pengotor. Mikrograf SEM menunjukkan bahwa Bi4Ti3O12 berbentuk plate-like sedangkan SrTiO3 berbentuk irregular spheres. Data UV-Vis DRS menunjukkan bahwa nilai energi celah pita Bi4Ti3O12/SrTiO3 dengan perbandingan mol (1/1), (1/2), (1/4), dan (1/6) berturut-turut adalah 3,178; 3,70; 3,137, dan 3,160 eV, dan aktivitas fotokatalitiknya terhadap metilen biru berturut-turut memiliki persen degradasi sebesar: 16,8307; 16,9891; 13,32,415 dan 20,8578%

Synthesis of Bi4Ti3O12 and Bi4Ti2.95V0.05O12 micro sheets via NaCl-KCl molten salt method

Bi4Ti3O12 is a tri-layer Aurivillius member compound that was reported to have good photocatalytic properties. Metal element doping and morphological particle tuning are strategies to increase photocatalyst activity. In this research, Bi4Ti3O12 and Bi4Ti2.95V0.05O12 microsheets were synthesized using NaCl/KCl molten salt method. SEM and X-ray powder diffraction pattern of the products show that the Bi4Ti3O12 and Bi4Ti2.95V0.05O12 microsheets were successfully synthesized. However, the Bi4Ti2.95V0.05O12 contains some impurities. UV-Vis DRS analysis of both samples resulting in a band gap energy of ~2.97 eV

Sintesis senyawa ABi2Ta2O9 (A= Ca, Sr, Ba) dengan metode lelehan garam tunggal NaCl

INDONESIA: Senyawa Aurivillius mempunyai peluang digunakan sebagai material fotokatalis sehingga dapat digunakan untuk mendegradasi limbah zat warna. Pada penelitian ini telah disintesis senyawa ABi2Ta2O9 (A= Ca, Sr, Ba) menggunakan metode lelehan garam tunggal NaCl, dan dilakukan uji aktivitas fotokatalitiknya dalam mendegradasi metilen biru. Hasil sintesis dikarakterisasi menggunakan, (a) instrumen (XRD) untuk menganalisa fasa yang terbentuk, (b) instrumen SEM-EDS untuk menganalisa morfologi, kandungan unsur senyawa, dan ukuran partikel, dan (c) UV-Vis DRS untuk menentukan energi celah pita. Difraktogram senyawa ABi2Ta2O9 (A= Ca, Sr, Ba) menunjukkan bahwa senyawa berhasil disintesis, namun masih ditemukan pengotor pada sampel (a) CaBi2Ta2O9 berupa fasa CaBi2O4 (b) SrBi2Ta2O9 berupa fasa Ta0,703O1,65; TaO1,6; Sr0,19Bi0,8O1,4, dan (c) BaBi2Ta2O9 berupa fasa Ta2O5; Bi4O7; TaO1,6. Mikrograph senyawa ABi2Ta2O9 (A= Ca, Sr, Ba) menunjukkan bahwa morfologi partikel berbentuk plate-like dengan rentang ukuran partikel adalah 1-5 µm dan masih terbentuk aglomerasi. Perhitungan spectra diffuse reflectance spectroscopy menggunakan persamaan Kubelka-Munk menunjukkan bahwa senyawa ABi2Ta2O9 (A= Ca, Sr, Ba) memiliki energi celah pita secara berurutan adalah 3,51; 3,21; 2,44 eV. Hasil uji degradasi larutan metilen biru menunjukkan bahwa material CaBi2Ta2O9, SrBi2Ta2O9, BaBi2Ta2O9 memiliki kemampuan mendegradasi secara berurutan sebesar 14,44; 24,23; 15,99 % selama 80 menit. Material SrBi2Ta2O9 memiliki aktivitas fotokatalitik yang paling tinggi karena energi celah pita yang lebih kecil dibandingkan CaBi2Ta2O9 dan ukuran partikel relatif lebih kecil dibandingkan ABi2Ta2O9 (A= Ca, Ba). ENGLISH: Aurivillius compound has the potential to be used as a photocatalyst material to degrade dye waste. In this study, the compound ABi2Ta2O9 (A= Ca, Sr, Ba) was synthesized using the molten NaCl salt method, and tested photocatalytic activity to degrading methylene blue. The results of synthesis, are characterized by (a) XRD instruments for analyzing the phases formed, (b) SEM-EDS instruments for analyzing morphology, compound element material, and particle size, and (c) UV-Vis-DRS instruments for determining bandgap energy. The diffractogram showed that ABi2Ta2O9 (A= Ca, Sr, Ba) indicates that the compound has form, but impurities were still found in the sample (a) CaBi2Ta2O9 in the form of phase CaBi2O4, (b) SrBi2Ta2O9 in the form of phase Ta0.703O1.65; TaO1.6; Sr0.19Bi0.8O1.4, and (c) BaBi2Ta2O9 in the form of Ta2O5 phase; Bi4O7; TaO1.6. The micrograph showed that shape of particle ABi2Ta2O9 (A= Ca, Sr, Ba) is plate-like with a particle size range is 1-5 μm and agglomeration is still formed. The calculation of diffuse reflectance spectroscopy using the Kubelka-Munk equation shows that the compound ABi2Ta2O9 (A= Ca, Sr, Ba) has a sequential band gap energy of 3.51, 3.21, 2.44 eV. The degradation test results of methylene blue solution showed that CaBi2Ta2O9, SrBi2Ta2O9, BaBi2Ta2O9 materials has the ability to degrade sequentially by 14.44; 24,23; 15.99 % for 80 minutes. SrBi2Ta2O9 material has the highest photocatalytic activity due to the smaller band gap energy compared to CaBi2Ta2O9 and relatively smaller particle size than ABi2Ta2O9 (A= Ca, Ba). ARABIC: يتمتع مركب أوريفيليوس (Aurivillius) بالفرصة كمواد محفز ضوئي بحيث يمكن استخدامه لتقليل نفايات الصبغة. في هذه الدراسة ، تم تصنيع المركب ABi2Ta2O9 (A= Ca, Sr, Ba) باستخدام طريقة ذوبان الملح الأحادي كلوريد الصوديوم ، ثم اختبار نشاطه التحفيزي الضوئي في تحلل الميثيلين الأزرق. تم وصف نتائج التوليف باستخدام (أ) أداة حيود الأشعة السينية (XRD) لتحليل المرحلة المشكلة ، (ب) أداة SEM-EDS لتحليل التشكل و محتوى العنصر المركب و حجم الجسيمات ، و (ج) فوق بنفسجي مرئي (UV-UV-Vis DRS)) لتحديد النطاق فجوة الطاقة. أظهر الحيود لمركب ABi2Ta2O9 (A= Ca, Sr, Ba) أن المركب قد تم تصنيعه بنجاح ، و لكن لا تزال توجد شوائب في العينة (أ) CaBi2Ta2O9 في شكل CaBi2O4 (ب) SrBi2Ta2O9 في شكل Ta0.703O1.65 ؛ TaO1.6 ؛ Sr0.19Bi0.8O1.4 ، و (ج) BaBi2Ta2O9 في شكل Ta2O5 ؛ Bi4O7 ؛ TaO1.6. أظهرت الصور المجهرية لمركبات ABi2Ta2O9 (A= Ca, Sr, Ba) أن شكل الجسيمات كان يشبه الصفيحة بنطاق حجم جسيمي يتراوح من 1 إلى 5 م ولا يزال يتشكل التكتل. أظهر التحليل الطيفي للانعكاس المنتشر أن المركب ABi2Ta2O9 (A= Ca, Sr, Ba) له طاقات فجوة نطاق تبلغ 3.51 ، 3.21 ، 2.44 فولت ، على التوالي. أظهرت نتائج اختبار التحلل لمحلول الميثيلين الأزرق أن المواد CaBi2Ta2O9 و SrBi2Ta2O9 و BaBi2Ta2O9 لديها القدرة على التحلل بالتتابع بمقدار 14.44 ؛ 24.23 ؛ 15.99٪ لمدة 80 دقيقة. تحتوي مادة SrBi2Ta2O9 على أعلى نشاط تحفيزي ضوئي بسبب طاقة فجوة النطاق المنخفضة مقارنةً ب CaBi2Ta2O9 و حجم الجسيمات الأصغر نسبيًا من ABi2Ta2O9 (A= Ca, Sr, Ba)

The molten salt synthesis of ABi2Ta2O9 (A = Ca, Sr, Ba) as photocatalyst material

The two-layer member of Aurivillius compound ABi2Ta2O9 (A= Ca, Sr, Ba) has been reported can be applied as photocatalyst material. In this research, the compound ABi2Ta2O9 (A= Ca, Sr, Ba) was synthesized using the molten salt method and measured photocatalytic act ivity to degrade methylene blue. Difractogram samples showed that the compound ABi2Ta2O9 (A= Ca, Sr, Ba) was successfully obtained but st ill found impurit ies on the samples. Micrograph samples showed that the particle morphology of ABi2Ta2O9 (A= Ca, Sr, Ba) was plate-like and found agglomerat ion in all part icles. The calculat ion using the Kubelka-Munk equat ion exhibited that CaBi2Ta2O9, SrBi2Ta2O9, BaBi2Ta2O9 sequent ially have bandgap energy of 3.51, 3.21, and 2.44 eV. The degradat ion test results of methylene blue solut ion show that CaBi2Ta2O9, SrBi2Ta2O9, and BaBi2Ta2O9 materials can degrade sequent ially by 14.44, 24.23, and 15.99 % for 80 minute