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Negative Ion Emission?

  1. Aug 8, 2012 #1
    Will more negative ions emit from an object (like a "negative ion generator") due to heat or piezoelectric effect or will they emit any way?

    Also, do certain objects give off more negative ions than others?
     
  2. jcsd
  3. Aug 8, 2012 #2
    Do you mean 'piezoelectric'...? are you sure you do not mean 'photoelectric'...?
     
  4. Aug 8, 2012 #3
    Well I do know that solar cells can do this.

    I'm trying to counter the claims of some products out there that say that b/c they're made of this or that they emit negative ions. For example, can a quartz crystal just sitting there emit negative ions? Not being stressed or pulsed.
     
  5. Aug 8, 2012 #4
    Some crystals do spontaneously polarize, causing a very small, temporary voltage difference. Some are also pyroelectric, which means that they create a voltage difference when the temperature changes. To my knowledge, they don't actually release negative ions, and if they did, they'd also be releasing positive ones. As for health benefits, there's no evidence that the tiny voltage difference against your skin will do any good, and you can get the same effect (but stronger) by licking a battery. If negative ions were released from the crystal, I'd expect that it would just rub off onto your skin, making the sweat/moisture on your skin more acidic and irritating the skin.
     
  6. Aug 8, 2012 #5

    Drakkith

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    Staff: Mentor

    Solar cells do not release negative ions. They absorb light and use the energy to promote electrons to a different energy level in the material, causing a current to flow in the process. We use this current to provide electrical power. I can't think of anything that simply releases negative ions unless a very high voltage is applied or you heat it up. (Such as the filament in a CRT that emits the electrons)

    In fact, this whole premise of "releasing negative ions" is nonsense.
     
  7. Aug 9, 2012 #6
    'In fact, this whole premise of "releasing negative ions" is nonsense.
    '

    It is a pity you had to say something so negative !!!!
    Electrons can be ejected from surfaces quite easily. I know that 'strictly speaking' they are not 'IONS'.... but they are charged particles so someone interested in this physics could see them as part of the story of ejection of 'ions'.
    In my opinion it is better to include relevant physics to help an explanation than to pooh pooh it.
    You really have to be prepared to explain why something is 'NONSENSE'
     
  8. Aug 10, 2012 #7

    Drakkith

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    Staff: Mentor

    I'm pretty sure the products the OP is talking about are scam, as the OP was asking about quartz crystals just sitting there without anything happening to them. The idea that different materials emit electrons without an external cause and not being radioactive is nonsense.
     
  9. Aug 10, 2012 #8
    OK.....I did not latch onto the crystals slant.
    At first read I thought it was a mix up between piezoelectric and photoelectric effects.
    Live & learn !!
     
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