Nothing is waste in this world. An innovative idea is used to generate electricity by using fish scales. Collagen in fish scale is used to produce piezoelectric impulses. Currently, industrial and manufacturing is the largest application market for piezoelectric devices. Strong demand also comes from medical instruments as well as information technology and telecommunications. The global demand for piezoelectric devices was valued at approximately US$14.8 billion in 2010. Development of biodegradable energy harvester from raw fish scales which could be trapped as a sustainable green energy source for next generation self-powered implantable medical devices.
Methodology
Fish scales, a by-product that is usually thrown away, contain collagen fibers that possess a piezoelectric property, which means that an electric charge is generated in them in response to mechanical stress.
The researchers have synthesized flexible bio-piezoelectric nanogenerator (BPNG) from this bio-waste. The bio waste is collected in the form of hard, raw fish scales from a fish processing market.
The scales are washed with running water and filtered to remove impurities. Then kept in oven 70⁰C to remove water from the fish scales. Then subjected to demineralization process using EDTA. Then it is dissolved in acetic acid to make them transparent and flexible. It is then made into thin sheets which are folded one over the another and compressed which creates a potential. The energy is harvested by keeping the electrodes on both sides and laminated them. The recycling of the fish by-products into the BPNG via one step process is a promising solution for the development of value-added products and also to reduce the e-waste. The nanogenerator also scavenges several types of ambient mechanical energies such as body movements, machine and sound vibrations, and wind flow which are abundant in living environment, and even repeated tapping with a finger. Repeatedly touching the BPNG with a finger can turn on more than 50 blue LEDs. The direct piezoelectric effect of fish scales from electricity generated by a bio-piezoelectric nanogenerator under mechanical stimuli - without the need for any post-electrical poling treatments.
Applications
It can also be used in self-powered implantable medical devices, surgeries, e-healthcare monitoring, as well as in vitro and in vivo diagnostics, apart from its myriad uses for portable electronics.
Conclusion
In the future, our goal is to implant a bio-piezoelectric nanogenerator into a heart for pacemaker devices, where it will continuously generate power from heartbeats for the device's operation. It will then degrade when no longer needed. Since heart tissue is also composed of collagen, our bio-piezoelectric nanogenerator is expected to be very compatible with the heart. Disposal of the fish bio-waste increases environmental pollution.