Related Experiment Video
Updated: Feb 5, 2026

A Polymer-based Piezoelectric Vibration Energy Harvester with a 3D Meshed-Core Structure
Published on: February 20, 2019
Hydrocapacitor for Harvesting and Storing Energy from Water Movement
Ruhao Liu1, Changhong Liu1, Shoushan Fan1
1Tsinghua-Foxconn Nanotechnology Research Center and Department of Physics , Tsinghua University , Beijing 100084 , China.
Abstract:
Based on porous carbon nanotube/polyaniline composite (CNT/PANI) and poly(vinyl alcohol) gel, we fabricated centimeter-sized hydrocapacitors with dual functions of energy conversion and storage with an efficient low-cost method. Owning to excellent hydrophily and large specific capacitance of CNT/PANI, the hydrocapacitors can easily convert energy from water movement induced by capillarity, gravity, or air pressure difference into electricity and store the generated electricity. Especially, sandwich-like hydrocapacitors outputted large current of 1.65 mA through an external load of 100 Ω, and hydrocapacitors showed good extendibility by connecting in series. To explain the mechanism of hydrocapacitors in this work, a possible model based on capillarity and traditional streaming potential was proposed and discussed. Hydrocapacitors here also provide a reference for future integration of nanogenerators and energy storage parts.
More Related Videos
Related Concept Videos
Energy Stored in a Capacitor
Energy Stored in Capacitors
By integrating the equation that relates voltage and current in a capacitor, one can derive an equation for the voltage across the capacitor at any given time. This equation is crucial in understanding and predicting the behavior of capacitors in...
Energy Stored in Inductors
In terms of gauging the energy stored within an inductor, it is equivalent to the integral of the power delivered at every individual moment, all...
Energy Stored in a Capacitor: Problem Solving
Capacitor-discharge ignition is a type of ignition system commonly found in small engines where the energy released from a capacitor ignites an induction coil that, in turn, fires the spark plug.
To calculate the energy stored in a capacitor of...
Energy Stored In A Coaxial Cable
In the simplest form, a coaxial cable can be represented by two long hollow concentric cylinders in which the current flows in opposite directions. The magnetic field inside and outside the coaxial cable is determined by using Ampère's law. The magnetic field inside...
What is Energy?

