What is the expression of the diffusion current?

What is the expression of the diffusion current?

Diffusion current = the movement caused by variation in the carrier concentration. Drift current = the movement caused by electric fields. Direction of the diffusion current depends on the slope of the carrier concentration. Direction of the drift current is always in the direction of the electric field.

How do you calculate diffusion density?

The diffusion current density can be calculated by equation 1. 1. Where e− = −1.602·10−19C is the elemental charge. Dp,n are the diffusion constants for hole and electrons, respectivly.

Which equation is used for measuring diffusion current in chemistry?

Ilkovic Equation: Ilkovic equation is a relation used in polarography relating the diffusion current (id) and the concentration of the non-polarisable electrode, i.e., the substance reduced or oxidised at the dropping mercury electrode (polarisable electrode).

How do you find current density?

The density of current is deduced from measured value of current intensity divided by the section area of wire in which there is a current circulation.

What is diffusion current in pn junction?

Diffusion current is holes and electrons moving from areas of high concentration, where they are the majority carrier, to areas of low concentration, where they become minority carriers. This occurs until they are uniformly distributed. Unlike drift, diffusion takes place without an electric field being present.

What are the units for current density?

Current density or electric current density is related to electromagnetism and is defined as the amount of electric current flowing through a unit cross-sectional area. It is a vector quantity. The SI unit of electric current density is ampere per square meter. The symbol “J” is used for electric current density.

What is Ilkovic equation in pharmaceutical analysis?

Ilkovic equation is a relation used in polarography relating the diffusion current (id) and the concentration of the depolarizer (c), which is the substance reduced or oxidized at the dropping mercury electrode. The Ilkovic equation has the form. id = k n D1/3m2/3t1/6c.

What is current density discuss?

What is conduction current density?

The conduction current density termed the amount of current or charges that flow through the conduction surface within a time t. Here, the conduction surface is always parallel to the current flow. Conduction current density formula Jc. = σE.

What is drift current density?

The current caused by the movement of charge carriers either by free electrons or holes per square unit area is referred to as the density of the drift current or Drift current Density.

What do you mean by drift and diffusion current density?

Hint: Drift current is the electric current due to the movement of charge carriers under the impact of an outer electric field, while diffusion current is the electric current due to the distribution of carriers, pointing to a change in carrier collection.