This work was supported by the National Natural Science Foundation of China (21606180), and the Natural Science Basic Research Program of Shaanxi (Program No. 2019JM-589).

1. Preparation of the BrSubPc
NOTE: The BrSubPc sample was prepared according to a previously published work36. The reaction is carried out in a double-row tube vacuum line system, and the reaction process is strictly controlled under water-free and oxygen-free conditions.
<ol>
	<li>Pre-treatment of raw materials
	<ol>
		<li>Weigh 2 g of o-dicyanobenzene, dry it in a vacuum oven for 24 h, take it out and then grind it carefully in an agate mortar.</li...

In this paper, we present a complete methodology for evaluating the catalytic performance of photocatalytic materials, including the preparation of catalysts, the investigation of factors affecting photocatalysis, and the performance of catalyst recycling. This evaluation method is universal and applicable to all photocatalytic material performance evaluations.
In terms of material preparation methods, many schemes have been reported for the preparation of rhombic dodecahedral Ag3PO...

Tetracyclines (TCs) are common antibiotics that provide effective protection against bacterial infections and are widely used in animal husbandry, aquaculture, and disease prevention1,2. They are widely distributed in water due to their overuse and improper application in the past decades, as well as the discharge of industrial wastewater3. This has caused severe environmental pollution and serious risks to human health; for example, the excessive presence of TCs in the aqueous environment can negatively affect microbial community distribution and bacterial resistance, leading to ecological imbalances, mainly due to the highly hydrophilic and bioaccumulative nature of antibiotics, as well as a certain level of bioactivity and stability4,5,6. Due to the hyper-stability of TC in the environment, it is difficult to break down naturally; therefore, many methods have been developed, including biological, physicochemical, and chemical treatments7,8,9. Biological treatments are highly efficient and low-cost10,11. However, because they are toxic to microorganisms, they do not effectively degrade and mineralize antibiotic molecules in water12. Although physicochemical methods can remove antibiotics from wastewater directly and quickly, this method only converts the antibiotic molecules from the liquid phase to the solid phase, does not completely degrade them, and is too costly13.
In contrast to conventional methods, semiconductor photocatalysis has been widely used for the degradation of pollutants in the past decades due to its efficient catalytic degradation properties14. For example, the noble metal-free magnetic FexMny catalyst of Li et al. achieved efficient photocatalytic oxidation of a variety of antibiotic molecules in water without the use of any oxidant15. Yan et al. reported the in situ synthesis of lily-like NiCo2O4 nanosheets on waste biomass-derived carbon to achieve efficient photocatalytic removal of phenolic pollutants from water16. The technology relies on a semiconductor catalyst excited by light to generate photogenerated electrons (e-) and holes (h+)17. The photogenerated e- and h+ will be converted into superoxide anion radicals (O2-) or hydroxyl radicals (OH-) by reacting with absorbed O2 and H2O, and these oxidatively active species oxidize and decompose organic pollutant molecules in water into CO2 and H2O and other smaller organic molecules18,19,20. However, there is no unified field standard for photocatalyst performance evaluation. The evaluation of a material&#39;s photocatalytic performance should be investigated in terms of the catalyst preparation process, environmental conditions for optimal catalytic performance, catalyst recycling performance, etc. Ag3PO4, with its prominent photocatalytic ability, has triggered substantial concern in environmental remediation. This new photocatalyst achieves quantum efficiencies of up to 90 % at wavelengths greater than 420 nm, which is significantly higher than previously reported values21. However, the severe photo corrosion and unsatisfactory electron-hole separation rate of Ag3PO4 limit its wide application22. Therefore, various attempts have been made to overcome these drawbacks, such as shape optimization23, ion doping24, and heterostructure building25,26,27. In this paper, Ag3PO4 was modified using morphology control as well as heterojunction engineering. First, rhombic dodecahedral Ag3PO4 crystals with high surface energy were prepared by solvent phase synthesis at room temperature under ambient pressure. Then, organic supramolecular BrSubphthalocyanine (BrSubPc), which can act as both electron acceptor and electron donor, was self-assembled on the silver phosphate surface by the solvothermal method28,29,30,31,32,33,34,35. The photocatalytic performance of the prepared materials was evaluated by investigating the effect of different environmental factors on the photocatalytic performance of the prepared samples to degrade trace amounts of tetracycline in water. This paper provides a reference for the systematic evaluation of the photocatalytic performance of the materials, which is of significance for the future development of photocatalytic materials for practical applications in environmental remediation.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>300 W xenon lamp</td>
			<td>CeauLight</td>
			<td>CEL-HXF300</td>
			<td></td>
		</tr>
		<tr>
			<td>AgNO3</td>
			<td>Aladdin Reagent (Shanghai) Co., Ltd.</td>
			<td>7783-99-5</td>
			<td></td>
		</tr>
		<tr>
			<td>Air Pump</td>
			<td>Samson Group Co.</td>
			<td>ACO-001</td>
			<td></td>
		</tr>
		<tr>
			<td>BBr3</td>
			<td>Bailingwei Technology Co., Ltd.</td>
			<td>10294-33-4</td>
			<td></td>
		</tr>
		<tr>
			<td>Constant temperature circulating water bath</td>
			<td>Beijing Changliu Scientific Instruments Co.</td>
			<td>HX-105</td>
			<td></td>
		</tr>
		<tr>
			<td>Dichloromethane</td>
			<td>Tianjin Kemiou Chemical Reagent Co., Ltd.</td>
			<td>75-09-2</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol</td>
			<td>Tianjin Fuyu Fine Chemical Co., Ltd.</td>
			<td>64-17-5</td>
			<td></td>
		</tr>
		<tr>
			<td>Fourier-transform infrared</td>
			<td>Bruker</td>
			<td>Vector002</td>
			<td></td>
		</tr>
		<tr>
			<td>Hexane</td>
			<td>Tianjin Kemiou Chemical Reagent Co., Ltd.</td>
			<td>110-54-3</td>
			<td></td>
		</tr>
		<tr>
			<td>HNO3</td>
			<td>Aladdin Reagent (Shanghai) Co., Ltd.</td>
			<td>7697-37-2</td>
			<td></td>
		</tr>
		<tr>
			<td>ICP-OES</td>
			<td>Aglient</td>
			<td>5110</td>
			<td></td>
		</tr>
		<tr>
			<td>K2HPO4</td>
			<td>Aladdin Reagent (Shanghai) Co., Ltd.</td>
			<td>16788-57-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Magnesium Sulfate</td>
			<td>Tianjin Kemiou Chemical Reagent Co., Ltd.</td>
			<td>10034-99-8</td>
			<td></td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Tianjin Kemiou Chemical Reagent Co., Ltd.</td>
			<td>67-56-1</td>
			<td></td>
		</tr>
		<tr>
			<td>NaOH</td>
			<td>Aladdin Reagent (Shanghai) Co., Ltd.</td>
			<td>1310-73-2</td>
			<td></td>
		</tr>
		<tr>
			<td>NH4NO3</td>
			<td>Sinopharm Group Chemical Reagent Co., Ltd.</td>
			<td>6484-52-2</td>
			<td></td>
		</tr>
		<tr>
			<td>o-dichlorobenzene</td>
			<td>Tianjin Fuyu Fine Chemical Co., Ltd.</td>
			<td>95-50-1</td>
			<td></td>
		</tr>
		<tr>
			<td>o-dicyanobenzene</td>
			<td>Sinopharm Group Chemical Reagent Co., Ltd.</td>
			<td>91-15-6</td>
			<td></td>
		</tr>
		<tr>
			<td>Scanning electron microscopy</td>
			<td>JEOL</td>
			<td>JSM-6390</td>
			<td></td>
		</tr>
		<tr>
			<td>Trichloromethane</td>
			<td>Tianjin Kemiou Chemical Reagent Co., Ltd.</td>
			<td>67-66-3</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultraviolet-visible Spectrophotometer</td>
			<td>Shimadzu</td>
			<td>UV-3600</td>
			<td></td>
		</tr>
		<tr>
			<td>X-ray diffractometer</td>
			<td>Rigaku</td>
			<td>D/max-IIIA</td>
			<td></td>
		</tr>
	</tbody>
</table>

a complete method for evaluating the performance of photocatalysts for the degradation of antibiotics in environmental remediation

Various antibiotics such as tetracycline, aureomycin, amoxicillin, and levofloxacin are found in large quantities in groundwater and soil systems, potentially leading to the development of resistant and multi-drug resistant bacteria, posing a threat to humans, animals, and environmental systems. Photocatalytic technology has attracted keen interest due to its rapid and stable treatment and direct use of solar energy. However, most studies evaluating the performance of semiconductor catalysts for the photocatalytic degradation of organic pollutants in water are currently incomplete. In this paper, a complete experimental protocol is designed to comprehensively evaluate the photocatalytic performance of semiconductor catalysts. Herein, rhombic dodecahedral silver phosphate was prepared by a simple solvent phase synthesis method at room temperature and atmospheric pressure. BrSubphthalocyanine/Ag3PO4 heterojunction materials were prepared by the solvothermal method. The catalytic performance of as-prepared materials for the degradation of tetracycline was evaluated by studying different influencing factors such as catalyst dosage, temperature, pH, and anions at atmospheric pressure using a 300 W xenon lamp as a simulated solar light source and a light intensity of 350 mW/cm2. Compared with the first cycle, the constructed BrSubphthalocyanine/Ag3PO4 maintained 82.0% of the original photocatalytic activity after five photocatalytic cycles, while the pristine Ag3PO4 maintained only 28.6%. The stability of silver phosphate samples was further tested by a five-cycle experiment. This paper provides a complete process for evaluating the catalytic performance of semiconductor catalysts in the laboratory for the development of semiconductor catalysts with potential for practical applications.

The rhombic dodecahedron Ag3PO4 was successfully synthesized using this solvent phase synthesis method. This is confirmed by the SEM images shown in Figure 1A,B. According to the SEM analysis, the average diameter of the rhombic dodecahedral structure was found to be between 2-3 &#181;m. The pristine BrSubPc microcrystals show a large irregular flake structure (Figure 1C). In the composite sample, the titanium dioxide still...

Watch this Scientific Journal Video about A Complete Method for Evaluating the Performance of Photocatalysts for the Degradation of Antibiotics in Environmental Remediation at JoVE.com

A Complete Method for Evaluating the Performance of Photocatalysts for the Degradation of Antibiotics in Environmental Remediation

Presented here is a protocol to explore a universal set of experimental procedures for comprehensive laboratory evaluation of photocatalysts in the field of environmental purification, using the example of photocatalytic removal of antibiotic organic pollutant molecules from water by phthalocyanine sensitized silver phosphate composites.

Various antibiotics such as tetracycline, aureomycin, amoxicillin, and levofloxacin are found in large quantities in groundwater and soil systems, ...

This paper provides a complete process for evaluating the catalytic performance of semiconductor catalysts in the laboratory to develop semiconductor catalysts with potential for practical applications. The advantage of this technique is that the photocatalytic performance of semiconductor catalysts can be evaluated in the laboratory in a more comprehensive manner. Demonstrating the procedure will be Bing Wang, a PhD student from the laboratory of Zhuo Li.And XuXia Zhang, LeCheng Li, MengTing Ji, Zheng Zheng, ChuanHui Shi, master students from the laboratory of Zhuo Li.To begin, prepare the reaction solution by dissolving six grams of ammonium nitrate in 200 milliliters of deionized water and treat with ultrasonic waves at 40 kilohertz frequency, 300 watt power for five minutes in one cycle to dissolve it completely then put it into a 500 milliliter volumetric flask to fix the volume.Add 2, 526 milliliters of deionized water to a beaker and then add 180 milliliters of ammonium nitrate solution, 54 milliliters of sodium hydroxide solution, and 120 milliliter of silver nitrate solutions sequentially to the beaker. Stir the solution vigorously for 10 minutes to prepare the diammine silver one complex. Finally, add 120 milliliters of potassium hydrogen phosphate solution to the complex and stir for five minutes.After the color of the solution changes from colorless to light yellow the precipitate obtained is silver phosphate rhombic dodecahedral. Separate the resulting precipitate by centrifugation at 7, 155 point 5G for 10 minutes at room temperature. Subsequently, centrifuge at three times with 50 milliliters of deionized water in the same conditions.Store the rhombic dodecahedral silver phosphate at room temperature in a dry environment away from light. Dissolved 5.77 milligrams of bromine subphthalocyanine in 50 milliliters of ethanol in a glass beaker and dissolve completely by sonication at 40 kilohertz frequency 300 watt power in one cycle for 30 minutes at room temperature. Then add 144.25 milligrams of silver phosphate to the above solution and sonicate at 40 kilohertz frequency, 300 watt power in one cycle for 30 minutes at room temperature.Stir the above solution in an 80 degrees Celsius water bath to allow complete evaporation of the ethanol. Dry the resulting brownish yellow powder overnight in an oven at 60 degrees Celsius and name the prepared sample as bromine subphthalocyanine silver phosphate For the test solution, 10 milligrams of tetracycline were dissolved in 500 milliliters of distilled water to obtain a 20 PPM solution. Then transfer 50 milliliters of the test tetracycline solution to a glass photocatalytic reactor.Stir the solution thoroughly with a magnetic stir at 1000 rpm, and maintain the temperature at 25 degrees Celsius. Then turn the air pump switch on and add the air to the solution at a rate of 100 milliliters per minute to obtain air saturation. Add 50 milligrams of the prepared photo catalyst to the test solution to reach a concentration of one gram per liter.Take the first sample immediately using a glass syringe. After stirring for 30 minutes in the dark, take the second sample and turn on the light source After a radiation for different time intervals, filter all the extracted samples through a 0.22 micrometer nylon membrane to remove solid particles before analysis. Store the filtered samples away from light in five milliliters centrifuge tubes until analysis.Measure the concentration of tetracycline with a UV visible spectrophotometer at 356 nanometers and evaluate the photocatalytic effect by the degradation rate as described in the manuscript. The SEM analysis shows that the average diameter of the rhombic dodecahedral structure was found to be between two to three micrometers, while bromine subphthalocyanine microcrystals show a large irregular flake structure. The photocatalytic activity of silver phosphate showed only 72.86%while bromine subphthalocyanine silver phosphate demonstrated 94.54%degradation of tetracycline after 30 minutes of visible light to radiation.The degradation rate constant by composites was 1.69 times higher than that of the silver phosphate. After five cycles, the composite showed a high tetracycline removal rate of 77.5%However, it decreased from 72.86%to 20.84%by silver phosphate. The XRD analysis of the composite showed that the peaks of the cycled samples did not change compared with the original samples, indicating good stability of the composite.Photocatalytic degradation shows that the absorption and removal of tetracycline increased as the photocatalyst concentration in the reaction solution increased. The effect of pH on the photocatalytic degradation of the composite material to remove tetracycline was slightly reduced in acidic solutions while more attenuated in neutral and alkaline solutions. The addition of anions had an inhibitory effect on the photocatalytic degradation of tetracycline, but the degradation rate was not overly affected.The effect of temperature on photocatalytic degradation for 30 minutes shows that the degradation rate of tetracycline gradually increased with the increase in temperature. Remember to turn on the circulating water switch to control the temperature at 25 degrees Celsius when performing the photocatalytic experiment.

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1.9K vistas.  Northwest University. Este documento proporciona un proceso completo para evaluar el rendimiento catalítico de los catalizadores semiconductores en el laboratorio para desarrollar catalizadores semiconductores con potencial para aplicaciones prácticas. La ventaja de esta técnica es que el rendimiento fotocatalítico de los catalizadores semiconductores se puede evaluar en el laboratorio de una manera más completa. Demostrando el procedimiento estará Bing Wang, un estudiante de doctorado del laboratorio de Zhu...