Meet the new power of the future, nano-power generation is coming

Our living environment is full of various energies, such as vibrational energy, chemical energy, biological energy, solar energy and thermal energy, etc., but most of these energies are not utilized or the utilization rate is extremely low. Nanogenerators are rule-based zinc oxide nanowires that convert mechanical energy into electrical energy in the nanometer range, and are known as the world's smallest generators.

Ubiquitous nanogenerators

Its advent completely broke the limit of people's understanding of the size of "generator". Nanogenerators can realize the collection and utilization of extremely small mechanical energy in the environment. For example, noise of various frequencies caused by the flow of air or water, the rotation of the engine, the operation of the machine, etc., the muscle contraction or the stepping of the foot to the ground when a person walks, or even caused by breathing, heartbeat or blood flow in the human body. A slight change in pressure somewhere in the body can drive a nanogenerator to generate electricity. Therefore, the nanogenerator theory provides an ideal power solution for the current realization of IoT and sensor networks as well as big data.

At present, nanogenerators can be divided into three categories: the first category is piezoelectric nanogenerators; the second category is triboelectric nanogenerators; the third category is pyroelectric nanogenerators. It is generally used in biomedicine, military, wireless communication, wireless sensing and other fields.

In the current era of rapid development of stretchable and wearable electronic devices, it is of great value and significance to study flexible mechanical energy harvesting devices. In recent years, research on assembling flexible triboelectric nanogenerators with flexible materials instead of commercial polymer films and metal sheets has become a bright spot. Recently, there have been many research achievements on flexible triboelectric nanogenerators.

Accurate testing of tiny signals is challenging

Due to the technical characteristics of nano-power generation itself, in the research process, it is necessary to test the electrical energy generated by the mechanical energy per unit area, and test the generated voltage, tiny current and power signal. The voltage is basically a few volts or even tens of volts, while the current is generally uA or even At the nA level, the power is at the mW or even uW level. It is difficult to accurately test small current and power signals, and the accuracy and stability of the test instrument are very high. Tektronix Keithley specializes in the testing of tiny electrical signals. Many Nobel Prize winners in physics in history have used and trusted Keithley testing instruments. In nano-power generation research, Keithley's products are still the industry's first choice, especially in small signal testing.

The theoretical limit of measurement sensitivity depends on the noise generated by the resistances in the circuit. Voltage noise is proportional to the square root of the product of resistance, bandwidth, and absolute temperature. As can be seen in the figure, the source resistance limits the theoretical sensitivity of voltage measurement, that is to say, when a 1uV signal with a 1Ω source resistance can be accurately measured, if the source resistance of the signal becomes 1TΩ, the measurement will become impossible. Because the measurement for 1uV at a source resistance of 1MΩ is close to the theoretical limit. At this time, it is impossible to complete this type of measurement by using a common digital multimeter. Choosing a suitable instrument is the premise to ensure accurate testing of small signals.

Nano Power Generation Test Solutions

Micro current signal test

Method: Insulating material nano power generation technology is used. Generally, the internal resistance of the source is at GΩ level and the test current is at pA level. Therefore, electrometer 6514 + Stanford SR570 (low noise current preamplifier) + special acquisition software are used in the industry to generate current. data collection.

Voltage Test Solution

Method: For the voltage signal test, it is recommended to use the new 4-series oscilloscope + voltage probe to test the V&T waveform data.