The Starting Material Concentration Dependence of Ag3PO4 Synthesis for Rhodamine B Photodegradation under Visible Light Irradiation

Synthesis of Ag3PO4 photocatalyst under the varied concentrations of AgNO3 and Na2HPO4·12H2O as starting material has been successfully synthesized using the co-precipitation method. The concentration of AgNO3 is 0.1; 0.5; 1.0; and 2.0 M, whereas Na2HPO4·12H2O is 0.03; 0.17; 0.33; and 0.67 M, respectively. The co-precipitations were carried out under aqueous solution. As-synthesized photocatalysts were examined to degrade Rhodamine B (RhB) under blue light irradiation. The results showed that varying concentrations of starting materials affect the photocatalytic activities, the intensity ratio of [110]/[200] facet plane, and their bandgap energies of Ag3PO4 photocatalyst. The highest photocatalytic activity of the sample was obtained by synthesized using the 1.0 M of AgNO3 and 0.33 M of Na2HPO4·12H2O (AP-1.0). This is due to the high [110] facet plane and increased absorption along the visible region of AP-1.0 photocatalyst. Therefore, this result could be a consideration for the improvement of Ag3PO4 photocatalyst

Tuning the Morphology of Ag3PO4 Photocatalysts with an Elevated Concentration of KH2PO4

Tuning the morphology of Ag3PO4 photocatalysts with an elevated concentration of KH2PO4 have been successfully conducted. This photocatalyst was prepared by starting material of AgNO3 and KH2PO4.  The KH2PO4 aqueous solution with five concentrations of 0.10 M, 0.15 M, 0.30 M, 0.45 M, and 0.60 M was reacted with AgNO3 aqueous solution. The products were characterized using X-ray Diffraction (XRD), UV-Vis Diffuse Reflectance Spectroscopy (DRS), and Scanning Electron Microscopy (SEM). The concentration of KH2PO4 significantly affected the morphology, size, and crystallinity of catalyst. The morphology of Ag3PO4 may be tuned with the synthesis using an elevated concentration of KH2PO4. The sample with the synthesis using 0.15 M of KH2PO4 exhibited the excellent photocatalytic activity. The high photocatalytic activity was caused by the small size of mixed morphology of sphere and tetrahedron, high crystallinity and defect sites.

Synthesis of Ag3PO4 using Hydrophylic Polymer and Their Photocatalytic Activities under Visible Light Irradiation

The highly active Ag3PO4 photocatalysts were successfully synthesized using the hydrophylic polymer of PVA (polyvinyl alcohol), PEG (polyethylene glycol) and PVP (polyvinyl pyrrolidone). The products were characterized using X-ray diffraction (XRD), Diffuse reflection spectroscopy (DRS), Field emission scanning electron microscope (FE-SEM), Brunauer–Emmett–Teller (BET) specific surface area, and X-ray photoelectron spectroscopy (XPS). Photocatalytic activities were evaluated using decomposition of Rhodamine B (RhB) under visible light irradiation. The results showed that the PVA, PEG, and PVP increased the specific surface area and enhanced the photocatalytic activity of Ag3PO4. The highest photocatalytic activity could be observed in Ag3PO4 synthesized with PVA, mainly due to an increase in electron excitation induced by PVA chemically adsorbed on the surface.

Visible Light Photocatalytic Properties of Ta and N Codoped SrTiO 3 Nanoparticles

Ta and N co-doped SrTiO 3 was synthesized by microwave-assisted solvothermal reaction using SrCl 2 ·6H 2 O, Ti(OC 3 H 7 ) 4 , TaCl 5 , and HMT (hexamethylenetetramine) in KOH and oleic acid mixed solutions. The products were characterized by XRD, TG-DTA, BET surface area measurement, TEM, EDX, DRS, PL-Spectra, and XPS. The nanoparticles of perovskite-type SrTi 1−x Ta x O 3−y N y (x = 0 − 0.1) were successfully synthesized. The photocatalytic activity of SrTiO 3 for DeNO x ability in the visible light region could be improved by the codoping of Ta 5+ and N 3− . The excellent visible light photocatalytic activity of this substance may be due to the generation of a new band gap by doping nitrogen that enables the absorption of visible light as well as a decrease in the incidence of the lattice defects, which acts as a recombination center of photo-induced electrons and holes by codoping with Ta 5+

Ointment Formulation of Arumanis Mango (Mangifera indica L.) Leaf Extract with Chitosan Tripoliphosphate Matrix as Antibacterial

This report presented the synthesis of Arumanis mango (Mangifera indica L.) leaf extract with chitosan tripolyphosphate matrix and its antibacterial activity. This research aimed to obtain an ointment formulation from mango leaf extract with chitosan tripolyphosphate matrix, to figure out the characteristics, including the particle morphology, and to determine the optimum formulation and the characterization of the antibacterial ointment. The research showed that extract morphology with chitosan tripolyphosphate was uneven-edge aggregates. Antibacterial tests were conducted on P. acnes and E. coli bacteria. The formula giving the greatest antibacterial activity was further utilized for the ointment preparations and then was characterized for 16 days. Formula C (chitosan and NaTPP  1: 0.0992(%)) gave the most excellent inhibition zone for P. acnes and E. Coli bacteria, at 7.94 mm and 10.02 mm, respectively. The obtained ointment preparation was white color homogeneous semi-solid with protective properties. The spreading power of the ointment was 5.25 – 6.25 cm, with the adhesive power of 1 – 5 seconds and pH of 6.0 – 6.4. The ointment's antibacterial activity was tested against P. acnes and E. coli bacteria using the formation of  inhibition zone method. The activity of ointment prepared on day one against P. acnes and E. coli was at 14.03 mm and 14.24 mm, respectively, while the activity on day 16 against P. acnes and E. coli was at 9.33 mm and 9.98 mm, respectively

Adsorption of Rhodamine B on Spherical Activated Carbon synthesized from Waste Bagasse Liquid using Hydrothermal Process

The dyes of the textile dyeing industry wastewater are harmful to humans and the environment. They should be treated before discharging into the environment. The adsorption using the spherical activated carbon can be effective to reduce the dyes. The spherical activated carbon of 3-7 µm in diameter was successfully prepared from the waste bagasse liquid using the hydrothermal method. The activation of this carbon was carried out using the KOH solution. The optimum pH and contact time were achieved in 2 and 200 min, respectively. Adsorption kinetic for RhB on activated spherical carbon follows the second-order kinetics and its adsorption mechanism follows the Langmuir isotherm. The maximum adsorption capacity of spherical activated carbon to Rhodamine B was achieved in 64.52 mg/g

The Phosphorus and Sulphur Distribution and Culturable Bacterial In Time Chronosequence of Ex-Tin Mining Ponds

The tin mining had caused ecological changes that can be occured to macro- and microecosystem. This article aims to study the pattern distribution of element of phosphorus (P) and sulphur (S) and also to identify culturable bacterial that were isolated form ex-tin mining ponds in time chronosequence. The elemets of P and S were detected by X-Ray Fluorescence (XRF) and the bacterials was isolated in medium agar and biochemistry identification by microbact. The concentration of element of P and S showed the average of P concentration increased in time chronosequnce of ex-tin mining ponds, whereas the average of S concentration showed dynamic pattern. In ex-tin mining pond with age 15 years were P (67,44 mg.L-1) and S (386,125 mg.L-1). While, the culturable bacterials were Kurthia spp; Actinobacillus equuli; Bacillus amyloliquefaciens; Bacillus spp; Micrococcus sp; Enterobacter gergoviae; Veillonella sp; Enterobacter aerogenes; Moraxella bovis; Nitrobater spp; and Enterobacter agglomerans