Question

(g)ICP source

Please try to draw out the structure of the device and briefly explain how it works.

Thank you so much.

Answer 1

SCHEMATIC DIAGRAM OF ICP SOURCE

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ICP Source

Abbreviation of ICP Source is referred as Inductive Coupled Plasma, Which comprises with a plasma Source. Electrical energy is supplied from the electromagnetic induction to the plasma source in which the magnetic fields varies with time.

ICP can be induced by handling the power of the radio frequency generator into gas which is relevant such as ICP argon. Helium and Nitrogen are also used. In this process, the plasma gas must be very pure, because the impurites of the gas will reduce the torch power.

Coupling in generated by transferring a high frequency electric current through a cooled induction coil, because of the induction of magnetic field. The inductor provokes a magnetic field which is oscillating in a rapid manner in the vertical plane of the coil. From the Tesla Coil there is a spark which show the flowing Argon gets ionised. Ionised Argon and the affiliated electrons gets collaborate with the fluctuating magnetic field. While Excitation there will be a Collision which results in the ionisation of more argon atoms with the sufficient energy produced. The resultant electrons from the magnetic field gets increased and diverted perpendicular to the torch. The temperature gets increased because the cations and electrons at high speed which is known as eddy current, makes a collision with the argon atoms which result in further ionisation. High Electron density at a steady state is formed rapidly within 2 minutes. 6000 -10000 K will be the temperature range in the plasma. In the high temperature Plasma which is on the top of torch, a long tail gets emerged. Here the Spectroscopic source is the torch. This torch comprises with atoms which is to be analysed and ions. These atoms and ions are excited by the heat of the plasma.

In a very limited time, more samples are determined with excellent tracking limit. It is mainly used in ICP Mass Spectrometry and ICP atomic emission Spectrometry.

Instrumentation

Sampler

In the Plasma Excitation area, the sample is converted to an aerosol by A Nebulizer.

Source

There are three electrodes in Plasma Source. Graphite anode is placed in each arm, and the tungsten Cathode is placed in the inverted base. ICP Argon, an inert gas with high velocity will isolate the excitation region and the analytical observation zone, and also produce high temperature plasma. The temperature of the excitation area is 6000K and it is located in a crook of the three electrodes. The plasma is squeezed to increase the current denstiy and plasma temperature.

Analyser

Mono or Poly Chromator act as an Analyser.

Detector

Signals are converted from the Radiant Energy by a Photomultiplier.