Learn About a Popular Topological Insulator Compound & its Uses

A topological insulator is an electrical insulator that flows electricity on the surface with the help of special electronic states. Many people raised a query, is bismuth sulfide (Bi2S3) a topological insulator? Range of microcircuits composed of a 10 nanometer-thick film of Bi2S3, an exotic material known as a topological insulator. It includes sheets of bismuth selenide. These sheets are ultra-thin and are highly flexible, conductive, and transparent. Many American scientists are studying topological insulators for future applications such as optical communications devices, sensors & electrodes for solar cells.

Bismuth Sulfide: A Popular Topological Insulator 

Bismuth sulfide is a widely used compound of bismuth. Wondering why? The reasons for great attention are because of its attractive properties and has many applications. It’s a modern technology era, so things that are outdated or of no use have no value. Here Bi2S3 plays a vital role. It is used for today’s advanced technology- sensors. Let’s know what types of sensors this highly used compound is applicable to: 

➤Humidity Sensor

It’s an electronic device that is used to measure humidity in its environment. Once it measures, then the sensor converts its findings into a corresponding electrical signal. Even smartphones are introduced containing this essential sensor. Many organizations (majorly manufacturing companies), hospitals, the automobile industry, etc., use humidity sensors. They are generally two types of humidity sensors- relative humidity (RH) sensors and absolute humidity (AH) sensors.

➤ Gas Sensor 

A gas sensor detects the different types of gases in the environment. The sensor is used to detect toxic gases or explosive gases which are hazardous to lives. The sensor is installed in factories & manufacturing industries to identify dangerous gases leaks. Home-based gas sensors are also introduced in the market that identifies smoke & carbon monoxide. Comes in various sizes and has different sensing abilities. The sensor is connected to an audible alarm to know people about the risk and make an emergency exit. 

Another Key Application 

The renowned compound is also used in many electronic devices and thermoelectric devices. One of its critical applications is in a thermoelectric power generator. It’s a solid-state device that either converts heat into electricity or transforms electrical energy into thermal power (used for heating & cooling). For instance, air conditioners, refrigerators, etc., which are daily used equipment, contain bismuth sulfide

Generally, every thermoelectric power generator has a similar basic configuration. Earlier metallic conductors were available, which were unfit to build thermoelectric generators to deliver more than 0.5% efficiency. However, after the 1950s, much research & development took place, which resulted in 2D topological insulators & semiconductors that contributed to creating high-tech devices. 

Thermoelectric devices are much used in personal & professional organizations. With the changed lifestyle, people want a convenient yet fast life. Thanks to modern technology making our lives easier. But the elements which are used to make these devices successful play a significant role. 


Till now, you have a better idea of how topological insulators contribute to high-tech devices. One of the key compounds -Bi2S3 is a vital 2D topological insulator that is widely used in humidity sensors, gas sensors, optoelectronic devices, electronic devices, and thermoelectric devices.