Fig a is the schematic diagram of DEG: an ITO glass slide is coated with a thin film of PTFE and an aluminium electrode is put on top of it. Drops of water act as the gate of the transistor and complete the circuit when they hit the surface of the glass. Fig b is the optical image showing four parallel DEG devices fabricated on the glass substrate.
A research team led by scientists from City University of Hong Kong (CityU) has recently developed a new form of droplet-based electricity generator (DEG).
It features a field-effect transistor (FET)-like structure that allows for high energy-conversion efficiency, and its instantaneous power density is increased by thousands of times compared to its counterparts without FET-like structure.
This groundbreaking achievement can help to advance scientific research into water energy generation and tackle the energy crisis.
The research was led by Professor Wang Zuankai from CityU’s Department of Mechanical Engineering; Professor Zeng Xiaocheng from the University of Nebraska-Lincoln, US; and Professor Wang Zhonglin, Founding Director and Chief Scientist at the Beijing Institute of Nanoenergy and Nanosystems of Chinese Academy of Sciences.
Their findings were published in the latest issue of the highly prestigious scientific journal Nature under the title “A droplet-based electricity generator with high instantaneous power density”.
A conventional droplet energy generator based on the triboelectric effect can generate electricity induced by contact electrification and electrostatic induction when a droplet hits a surface. However, the amount of charge generated on the surface is limited by the interfacial effect, and as a result, the energy conversion efficiency is quite low.
In order to improve the conversion efficiency, the research team has spent two years developing the DEG. Its instantaneous power density can reach up to 50.1 W/m2, thousands of times higher than similar devices without the use of the FET-like design. The energy conversion efficiency is also markedly higher.
Professor Wang pointed out that there are two crucial factors for the invention. First, the team found that the continuous droplets impinging on PTFE, an electret material with a quasi-permanent electric charge, provides a new route for the accumulation and storage of high-density surface charges. They found that when water droplets continuously hit the surface of PTFE, the surface charge generated will accumulate and gradually reach saturation. This new discovery has helped to overcome the bottleneck of the low-charge density encountered in previous work.
Research shows that a drop of water released from a height of 15cm can generate a voltage of over 140V, which can light up 100 small LED lights.
Another key feature is a unique set of structures similar to the FET that won the Nobel Prize in Physics in 1956 and has become the basic building block for modern electronic devices. The device consists of an aluminium electrode and an indium tin oxide (ITO) electrode with a film of PTFE deposited on it. The PTFE/ITO electrode is responsible for the charge generation, storage, and induction. When a falling water droplet hits and spreads on the PTFE/ITO surface, it naturally “bridges” the aluminium electrode and the PTFE/ITO electrode, translating the original system into a closed-loop electric circuit.
With this special design, a high density of surface charge can be accumulated on the PTFE through continuous droplet impinging. Meanwhile, when the spreading water connects the two electrodes, all the stored charges on the PTFE can be fully released for the generation of electric current. As a result, both the instantaneous power density and energy conversion efficiency are much higher.
“Our research shows that a drop of 100 microlitres [1 microlitre = one-millionth litre] of water released from a height of 15 cm can generate a voltage of over 140V, and the power generated can light up 100 small LED lights,” said Professor Wang.
Professor Wang said he hoped that the outcome of this research would help to harvest water energy to respond to the global problem of renewable energy shortage. He believed that in the long run, the new design could be applied and installed on different surfaces, where liquid is in contact with a solid, to fully utilise the low-frequency kinetic energy in water. This can range from the hull surface of a ferry to the surface of umbrellas or even inside water bottles.
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
Droplet-based electricity generator
- Single-cell RNA sequencing reveals developmental heterogeneity among Plasmodium berghei sporozoiteson February 22, 2021 at 5:40 am
scRNA-seq requires partitioning and lysis of single cells, conversion of RNA into cDNA, and cDNA amplification to generate sequencing ... are high-throughput droplet-based methods 27,28,29.
- Advancing Rapid Point-of-care Viral Diagnostics to a Clinical Settingon February 19, 2021 at 4:00 pm
Future Virology. 2015;10(3):313-328. Initial direct antigen POC immunoassays were derivatives of standard microtiter plate-based ELISAs and were configured primarily in flow-through or ...
- Global Automotive Health, Wellness and Wellbeing Markets Report 2020-2025 - Growth Opportunities and Strategies for Automotive OEMson February 17, 2021 at 1:40 am
Meanwhile, Droom, the aftermarket player is offering an antimicrobial surface protection shield for cars and two-wheelers which will be effective against SARS and other droplet-based viruses.
- Renewable energy: Drop of water can light up 100 LED bulbson February 9, 2021 at 4:01 pm
A research team led by scientists from the City University of Hong Kong (CityU) has recently developed a droplet-based electricity generator (DEG), featured with a field-effect transistor (FET)-like ...
- Droplet printing reveals the importance of micron-scale structure for bacterial ecologyon February 7, 2021 at 4:00 pm
Here we develop a droplet-based printing method to arrange bacterial ... Our work provides a method to generate customised bacterial communities with defined spatial distributions, and reveals ...
Go deeper with Google Headlines on:
Droplet-based electricity generator
Go deeper with Bing News on:
- Outdoors: Cold water puts fish in energy-saving modeon February 28, 2021 at 11:38 am
While, at times, the wind might be blowing 40 miles an hour and whipping snow into freestyle curvy architecture across the landscape, and the elements can throw daggers of Arctic cold fronts and ...
- Don’t Believe the U.S. Energy Independence Hypeon February 28, 2021 at 9:27 am
The U.S. is energy independent, right? Well, that’s what some politicians would have you believe, but it’s not really true in any meaningful sense of the word “independent.” In its broadest sense, ...
- The Official Water of the UFC is a Monster Energy Drinkon February 26, 2021 at 8:41 am
The UFC and Monster Energy have agreed to a new three year deal according to Ariel Helwani. Normally, we would not care about this or take note at all. There's ...
- PWP Offering Money-Saving Water & Energy Direct Install Program (WeDIP) to Qualified Customerson February 25, 2021 at 6:31 pm
Now you can do just that with the help of the Water and Power Department’s Water & Energy Direct Install Program (WeDIP) in which PWP will install water and energy-saving equipment — completely free ...
- Energy And Water Development Corp. Pays Off Its Convertible Loanson February 25, 2021 at 2:55 pm
Energy and Water Development (OTCQB: EAWD) is pleased to report that it has paid off the convertible loans issued during years 2019 and 2020. All of the convertible loans were paid off to avoid ...