Energy Harvesting Using High-Strength and Flexible 3D-Printed Cellulose/Hexagonal Boron Nitride Nanosheet Composites

Abstract

As a natural polymer, cellulose is abundant, low-cost, robust, and biodegradable and can be chemically modified. This work explores the enhancement of mechanical, thermal, and flexoelectric properties of three-dimensional (3D)-printed carboxymethyl cellulose (CMC) due to the addition of mechanically exfoliated hexagonal boron nitride (hBN). hBN was observed to act as a rheology modifier, and CMC reinforced with 2% hBN exhibited the maximum apparent viscosity of 12.24 Pa•s at a shear rate of 100 s −1 . The 0.5% hBN/CMC film exhibited the highest mechanical and thermal stability. A flexoelectric energy harvester was fabricated out of 3D-printed hBN/CMC composites to test the effectiveness of strain-induced charge production. By varying the load resistance and applied pressure, we were able to measure the voltage and current flowing through the device. We found that a load resistance of 180 kΩ connected across a 2% hBN/CMC device resulted in the highest power delivery of 5.5 nW. When mechanical strain is applied, a charge state fluctuation and spontaneous polarization in the hBN/CMC matrix are seen. This phenomenon can be explained based on the flexoelectric energy-harvesting mechanism, supported by density functional theory (DFT) calculations.

3D-printed flexible energy harvesting devices designed using non-layered two-dimensional natural tourmaline silicates

“…Because the dipoles cannot spin as quickly as the frequency changes, the dielectric constant value decreases at higher frequencies. 24…”

“…3D printing/additive manufacturing techniques enable the fabrication of stable and homogeneously distributed 2D sheet-based structures with high strength and flexibility. 22–24 Flexible devices can also be fabricated using substrates like polymer films, fabrics, papers, etc. 25,26 The topological coating of these materials provides great energy outputs.…”

Lead-Free Piezoelectric Energy Harvester Based on 2D Bismuth Titanate

“…A practical solution to this global crisis is harvesting energy from the novel properties of multifunctional nanomaterials. The ability to convert even minute mechanical vibrations into active energy sources makes piezoelectric materials potential energy harvesters. , The capacity of a piezoelectric material to improve the energy conversion efficiency of micromechanical forces essentially acts as a platform for nanoelectronics and nanoenergy generators.…”

Multifunctional Cellulose Nanofibrils–GdF3 Nanoparticles Hybrid Gel and Its Potential Uses for Drug Delivery and Magnetic Resonance Imaging

“…The abundance of the surface hydroxy groups renders the CNF highly hydrophilic and gives rise to interfibrillar interactions due to hydrogen bonds, leading to fibril agglomeration. As a result, CNF gels exhibit a cross-linked 3D network and rheological behaviors, such as viscoelasticity and shear-thinning, which makes CNF gels well suited for 3D gel printing. , …”