What is the work function of the metal?
What is the work function of the metal?
The work function (WF) of a metal can be defined as the minimum energy required to extract one electron from a metal. Obviously the WF is one of the fundamental electronic properties of bare and coated metallic surfaces.
How do you find the work function on a graph?
This is an identical form to y = mx + b. So if you want to find the work function, you find the y-intercept, and then divide by e. As a bonus, the graph also gives you the ability to find “h”, Planck constant, by finding the slope and dividing that by e as well.
How do you determine the work function of a metal?
Work function measurement techniques: The work function of a material can be measured with PES and Kelvin probe (KP). While PES allows the measurement of the absolute work function, KP only gives the contact potential difference (CPD) between the actual probe and the sample surface.
Which metal has the higher work function?
The highest known metal work function is approximately 6.35 eV for platinum (Pt) and lowest work function is 2.14eV for cesium. Work function can be said as the minimum energy needed to move an electron from the Fermi level into vacuum.
Why do metals have different work functions?
Different metals have different values of work function because of difference in their electronegativity. The least electronegative (or most electropositive) metal would let go of its valence electron very easily compared to those metals with higher values of electronegativity.
Does work function depend on metal?
Note: Work function depends upon the structure and chemical composition of a surface. On the other hand side, platinum is the highest knowing metal work function and the lowest work function metal is cesium….
| ELEMENTS | WORK FUNCTION (eV) |
|---|---|
| Platinum | 6.35 |
| Selenium | 5.11 |
| Silver | 4.26-4.73 |
| Sodium | 2.28 |
Is work function same for all metals?
Is different for different metals. Hint: The different metals consist of different values of work function because of difference in their electronegativity behaviour. Therefore the work function is that amount of energy which is required to get an electron out of the metal plate without any kinetic energy.
Which metal has less work function?
The work function of caesium metal is 2.14 eV.
Do metals have different work functions?
Do metals have a frequency?
The threshold frequency of a metal refers to the frequency of light that will cause an electron to dislodge from that metal. Light below a metal’s threshold frequency will not eject an electron. Light above the threshold frequency will eject an electron with some kinetic energy.
Which is the work function of a material?
Work Function. The y-intercept is the work function of the material. For any frequency less than the threshold frequency, it’s like the electron is in a deep hole. As the frequency goes from zero to higher values, the electron is lifted higher out of the hole, until finally at its threshold frequency it’s out.
How is threshold frequency different for different metals?
The value of threshold frequency is different for different metals. Here, the vertical axis represents the energy of an electron, and the horizontal axis represents the frequency.
How is kinetic energy gain related to work function?
The gain of kinetic energy of an electron is the difference between incident photon energy and work function of the metal or material and that can be represented as Where, φ is the work function of the metal and E k is the kinetic energy gain of the electron. The equaltion can be rewritten as Where f o is threshold frequency of the metal.
Which is the best description of work function?
The minimum energy required just to escape an electron from a metal surface is known as work function. Work function can also be explained and defined by quantum physics. For that, we first have to know some basic features. Sir Albert Einstein said that light is in the form of a beam of a huge number of discrete energy packets called photons.