Objects can also have a sense of touch, taste and smell! How will sensor technology evolve?

Recently, the internationally renowned academic journal Nature reported the latest scientific research results of a wearable sensor. This wearable sensor is translucent when turned off, and can see incident infrared light when turned on, allowing the wearer to detect infrared light that is invisible to the human eye. This technology can help doctors observe diseased tissues during surgery.

So, what is a sensor? Simply put, a sensor is a device that monitors things and their changes in the environment, and sends the monitored information to other electronic devices, such as computers, for further processing. To make it easier to understand, we use the five senses of the body as an analogy with the brain. The eyes can see the colorful world, the ears can hear beautiful music, the nose can smell the fragrance of flowers, and the mouth can taste delicious food. The eyes, ears, nose and other five senses transmit the collected information to the brain, so that we can experience the beauty of life. Here, our eyes and ears are equivalent to sensors, and the brain is equivalent to a computer processor.

Sensors are widely used in daily life, for example, table lamps that can adjust brightness by touching different times, voice-controlled lights in corridors, and various devices that measure temperature, pressure or flow. The existence and development of sensors have given objects senses such as touch, taste, and smell, so objects have gradually come alive.

Chemical sensors are a type of special sensor used to monitor and sense chemical substances. They are usually used to monitor specific chemical components in gases or liquids and convert the chemical signals into current or voltage signals. In other words, chemical sensors can monitor various properties of chemical substances, such as concentration and composition, and convert them into electrical signals.

In life, due to the limitations of smell, people cannot identify carbon monoxide and are poisoned unknowingly. The emergence of chemical sensors has broken through the limitations of human senses. Chemical sensors can be prepared using semiconductors that are sensitive to carbon monoxide, which can conveniently and quickly monitor the carbon monoxide content in the room to prevent poisoning.

An ideal chemical sensor requires high sensitivity, good selectivity, long-term stability, and fast response. Chemical sensors are affected by the external environment, so their performance parameters and indicators should be optimized to the greatest extent.

The functional realization of chemical sensors includes two main steps, namely recognition and conduction. In the recognition step, the object to be measured selectively interacts with the sensor recognition element, resulting in a change in the physical parameter. This change is fed back through the sensor that generates an output signal. Chemical sensors are made of semiconductor materials, ceramic materials, temperature-sensitive materials, luminescent materials, etc., and are widely used in scientific research, chemical industry, various testing institutions, such as clinical medicine, industrial processes and environmental monitoring. The development of chemical sensors has promoted the progress of society and allowed us to truly feel the development of science and technology in our lives.

Non-invasive wearable chemical sensors have gained great attention in the field of personal health monitoring and medical diagnosis. Compared with traditional diagnostic methods, these sensors provide non-invasive, real-time and continuous monitoring and analysis. Designs of wearable chemical sensors include tattoos, clothing and accessories. The successful development of non-invasive wearable chemical sensors will effectively help people manage their personal health, prevent potential diseases, and ultimately improve people's quality of life.

With the rapid development of science and technology, chemical sensor technology has gradually received more attention. The development trend of modern sensor technology is to develop new materials, new processes and new sensors, and to achieve multi-functionality, high precision, integration, intelligence, miniaturization, and wireless networking. In the future, chemical sensors will be widely used in environmental protection and monitoring, disease prevention and treatment, and to improve people's quality of life.

(The first author is a professor and doctoral supervisor at Northwest Normal University, and the second author is a master's student at Northwest Normal University)