# What is the mass of an electron hole?

## What is the mass of an electron hole?

For electrons or electron holes in a solid, the effective mass is usually stated in units of the rest mass of an electron, me (9.11×10−31 kg).

What is photogenerated carriers?

Photogenerated carriers are injected into the overlayer and are transported therein by virtue of a special charge-transport material dissolved in the layer. From: Encyclopedia of Physical Science and Technology (Third Edition), 2003.

Does TiO2 have a direct band gap?

TiO2 Anatase is an indirect band gap semiconductor and possesses a band gap value of ~3.2-3.35 eV if it is in the thin film state.

### Is TiO2 direct or indirect?

In general, anatase TiO2 exhibits higher photocatalytic activities than rutile TiO2. The results indicate that anatase appears to be an indirect band gap semiconductor, while rutile and brookite belong to the direct band gap semiconductor category.

Do electrons have rest mass?

The rest mass of the electron is 9.1093837015 × 10−31 kg, which is only 1/1,836the mass of a proton. An electron is therefore considered nearly massless in comparison with a proton or a neutron, and the electron mass is not included in calculating the mass number of an atom.

Do electrons and holes have the same mass?

The concept of effective mass follows from physicists’ love for simple relations such as Ohm’s law (current density = conductivity x electric field intensity) or Newton’s second law of motion (acceleration = force / mass). From this follows that the hole effective mass is often larger than the electron effective mass.

#### What is photo generation?

Filters. (physics) The generation of something (especially of electrical energy) by light. noun.

Why do we call a solar cell a minority carrier device?

The applied voltage upsets the steady-state balance between drift and diffusion, which unleashes the flow of diffusion current. Since the conduction through the junction happens via minority carriers, the p-n junction is called a “Minority carrier device.”

What is the difference between rutile and anatase titanium dioxide?

The key difference among them is in their appearance. Anatase Titanium Dioxide is colorless, whereas Rutile Titanium Dioxide is usually found in dark red appearance. Rutile titanium dioxide is optically positive, whereas Anatase titanium dioxide is optically negative.

## What is band gap in conductors?

A band gap is the distance between the valence band of electrons and the conduction band. Essentially, the band gap represents the minimum energy that is required to excite an electron up to a state in the conduction band where it can participate in conduction.

What is direct and indirect band gap semiconductor?

The band gap is called “direct” if the crystal momentum of electrons and holes is the same in both the conduction band and the valence band; an electron can directly emit a photon. Indirect bandgap materials include crystalline silicon and Ge. Some III-V materials are indirect bandgap as well, for example AlSb.

Can electrons be seen?

Now it is possible to see a movie of an electron. Previously it has been impossible to photograph electrons since their extremely high velocities have produced blurry pictures. In order to capture these rapid events, extremely short flashes of light are necessary, but such flashes were not previously available.