Energy harvester with efficient electrokinetic power conversion and generation using pseudo-streaming effect of MXene

Abstract

for example, tens of thousands of unit devices are required to reach mW scale of power generation. In this study, we utilize titanium carbide (Ti3C2) MXene nanosheets, which have metallic conductivity with the two-dimensional feature, to improve the electrokinetic energy conversion efficiency of the transpiration-driven electrokinetic power generator (TEPG). The MXene based transpiration-driven electrokinetic power generator (MTEPG), where MXene nanosheets are coated on cotton fabric, derived fast nano-flow of water through the layered structure for a high pseudo-streaming current of 78 μA. The intensive affinity toward cation enables the MTEPG to generate high voltage and current of 0.68 V and 2.73 mA by asymmetrically dropped NaCl solution. Furthermore, adding polyaniline(PANi) into MPETG enhances the ionic diffusion while maintaining the Ti3C2 MXene nanosheet network. The Ti3C2/PANi composite-based transpiration-driven electrokinetic power generator (MPTEPG) generated a maximum voltage and current of 0.54 V and 8.2 mA, with a maximum power density of 30.9 mW/cm3. Highly efficient MPTEPG could operate low-power electronics and charged the commercialized battery for the first time with a total device volume of 6.72 cm3.

Nano-hydroelectric technology utilizes hydraulic flow through nanomaterials to generate electricity, which has gained increased attention due to its simplicity, renewability, and ubiquity. For the past few years, most of nano-hydroelectric devices have been devised using the liquid or vapor phase of water as a source of energy conversion. Unfortunately, the reported energy conversion efficiencies of even the state-of-the-art hydroelectric generators are not sufficient for practical applications