Stabilization of Ferroelectric Domains via Interfacial Strain in HoFeO3- BaTiO3 Nanofiber Heterostructures for Enhanced Hybrid Energy Harvesting

Smita Chaturvedi; Swathi Krishna; Shivshankar Jokare; Supriya Sahoo; Vikash Kushwaha; Priyank Shyam; Mandar Shirolkar; R. Boomishankar

arXiv · 2610.26611

Stabilization of Ferroelectric Domains via Interfacial Strain in HoFeO3- BaTiO3 Nanofiber Heterostructures for Enhanced Hybrid Energy Harvesting

Smita Chaturvedi·Swathi Krishna·Shivshankar Jokare·Supriya Sahoo·Vikash Kushwaha·Priyank Shyam·Mandar Shirolkar·R. Boomishankar

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Abstract

Piezoelectric nanogenerators (PENGs) are an attractive platform for self-powered mechanical-energy harvesting, but their output is often limited by depolarization fields, charge leakage, and inefficient stress transfer to the active dipoles, particularly in polymer-dominated composites. Here we report HoFeO3-BaTiO3 (HFO-BTO) nanofiber heterostructures prepared by alternating sol-gel electrospinning, in which orthorhombic HoFeO3 (Pbnm) and tetragonal BaTiO3 (P4mm) coexist in intimate contact. Rietveld-refined X-ray diffraction, high-resolution transmission electron microscopy, and Raman spectroscopy indicate interfacial lattice distortion. Polarization-electric field loops show that the heterostructure retains a polarization comparable to that of BaTiO3 (16.39 vs 15.80 microcoulombs per square centimeter at zero field) while its switching-current maximum moves to a higher field (about 7 vs about 3.5 kilovolts per centimeter), consistent with strain-stabilized ferroelectric domains. When the nanofibers are encapsulated in polydimethylsiloxane (PDMS) and excited under cyclic impact, the device produces a hybrid output: the piezoelectric response of the strained BaTiO3 is supplemented by a triboelectric contribution from contact electrification. The HFO-BTO device delivers open-circuit voltage peaks of about +6 volts and -8 volts and a power density of 24.31 microwatts per cubic centimeter at a 4.7 megaohm load. This is 2.4 times the value for an identically fabricated BaTiO3 device (10.00 microwatts per cubic centimeter) and 8.7 times that of the HoFeO3 device (2.78 microwatts per cubic centimeter). These results link interface-driven lattice distortion to improved electromechanical output and identify all-oxide nanofiber heterostructures as a promising route to lead-free energy harvesting.

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Smita Chaturvedi, Swathi Krishna, Shivshankar Jokare, Supriya Sahoo, Vikash Kushwaha, Priyank Shyam, Mandar Shirolkar, R. Boomishankar. 2026-10-19. Stabilization of Ferroelectric Domains via Interfacial Strain in HoFeO3- BaTiO3 Nanofiber Heterostructures for Enhanced Hybrid Energy Harvesting. https://arxiv.org/abs/2610.26611

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