Piezoelectric paper fabricated via nanostructured barium titanate functionalization of wood cellulose fibers.

We have successfully developed hybrid piezoelectric paper through fiber functionalization that involves anchoring nanostructured BaTiO3 into a stable matrix with wood cellulose fibers prior to the process of making paper sheets. This is realized by alternating immersion of wood fibers in a solution of poly(diallyldimethylammonium chloride) PDDA (+), followed by poly(sodium 4-styrenesulfonate) PSS (-), and once again in PDDA (+), resulting in the creation of a positively charged surface on the wood fibers. The treated wood fibers are then immersed in a BaTiO3 suspension, resulting in the attachment of BaTiO3 nanoparticles to the wood fibers due to a strong electrostatic interaction. Zeta potential measurements, X-ray diffraction, and microscopic and spectroscopic analysis imply successful functionalization of wood fibers with BaTiO3 nanoparticles without altering the hydrogen bonding and crystal structure of the wood fibers. The paper has the largest piezoelectric coefficient, d33 = 4.8 ± 0.4 pC N(-1), at the highest nanoparticle loading of 48 wt % BaTiO3. This newly developed piezoelectric hybrid paper is promising as a low-cost substrate to build sensing devices.