Can anyone suggest a suitable lamp for photo-catalytic degradation. i have seen in many literature they used xenon and mercury as UV source. which one is better ?
They are both very expensive. You may think about LEDs, they are cheap but not very powerful.
I have the same opinion with Yurii V Geletii.
LEDs are cheaper and you can select bulbs emitting light in desired wavelength region, no need cutoff filter.
There are a number of things to consider including the objectives of your experiments. What is the photocatalyst and what wavelengths are required? Do you want to exclude photolysis as a degradation mechanism? What scale (volume) and geometry of system will you work with?
Hi,
I have had good results for degradation of emerging pollutants (pharmaceuticals), using low pressure mercury lamps (254 nm), but it is better to use medium pressure mercury lamps to obtain complete mineralization. It is also very important the geometry of the reactor that you use.
I use mercury lamps to generate UV source. UV-A is better for photocatalysis (less photolysis). If you use UV-C, more photolysis will occur instead of photocatalysis. Never use xenon or LEDs as these lamp shapes do not fit my photoreactor setup.
I aggree in the contributions of William, Valeria and Collin. We are using low or middle pressure lamps.. middle pressure can be designed/adapted better to the wavelength you need but you need more energy. Photocatalysis needs aprox. 380-400nm. So what is your design and application?
CHOICE OF LAMP DEPENDS ON BAND GAP OF PHOTOCATLYTIC MATERIAL, ACCORDINGLY YOU CAN SELECT xenon lamp OF 300W FROM WHICH YOU CAN EXTRACT 1SUN IRRADIATION(AM1.5G) OR Hg LAMP.........
The comment and questions of William are very correct. First of all which is the application? Plenty of research is now devoted to VIS-activated photocatalysis.
Secondly, as most of the answers hinted, there is a difference between the radiation wavelength (energy) and its intensity. One will influence the thermodynamics, the other one the kinetics. So it is actually about "what?" and "how many?"
Excilamps can help youexcilamp can help you.
http://www.hcei.tsc.ru/en/cat/technologies/tech10.html
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