Abstract
Conventional thermoelectric materials are limited by rigidity, high synthesis costs, and poor compatibility with flexible devices. Despite progress, the development of novel, low-cost, and scalable materials for flexible thermoelectrics remains limited. The novelty of this work lies in introducing InTe as a printable thermoelectric material and demonstrating the first screen-printed flexible thermoelectric generators (FTEGs) based on InTe. Pristine and Bi/Se co-doped InTe were synthesised via solid-state reaction and fabricated through a cost-effective, scalable screen-printing method. Co-doping effectively tuned the crystallinity, carrier concentration, mobility, and band structure. Among the co-doped samples, In0.94Bi0.06Te0.97Se0.03 achieved a Seebeck coefficient of ~ 1320 µV/K and showed a maximum power output of ~ 29.45 nW at a temperature gradient of 100 K. The other novelty of this work is the incorporation of MnO₂ to form a printed p–n heterojunction, which improves the conductive pathway, leading to a peak power output of 48.41 nW, approximately 1.64 times higher than that of the In0.94Bi0.06Te0.97Se0.03 sample. The FTEGs exhibited approximately 2% resistance variation after 500 bending cycles and at various angles, confirming excellent mechanical durability. This work establishes InTe as a promising printable thermoelectric material and highlights co-doping and MnO2 incorporation as powerful strategies for flexible energy harvesting.
Data availability
The datasets used and analysed during the current study are available from the corresponding author on reasonable request.
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Acknowledgements
The author gratefully acknowledges the financial support from MAHE under the Dr. T. M. A. Pai Doctoral Fellowship. ANP sincerely appreciates the intramural funding that MAHE (MAHE/CDS/PHD/IMF/2022) provides to support this research.
Funding
Open access funding provided by Manipal Academy of Higher Education, Manipal. Intramural funding provided by Manipal Academy of Higher Education (MAHE/CDS/PHD/IMF/2022).
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Manasa R Shankar : Conceptualisation, Methodology, Data curation, Data Analysis, writing original draft. A N Prabhu : Supervision, resources, formal analysis, writing review & editing. Ramakrishna Nayak : Conceptualisation, Validation, Resources, Technical support, writing review & editing.
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Shankar, M., Prabhu, A. & Nayak, R. Unveiling InTe for flexible thermoelectric applications with enhanced performance via Bi/Se co-doping and MnO₂ integration. Sci Rep (2026). https://doi.org/10.1038/s41598-026-35782-1
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DOI: https://doi.org/10.1038/s41598-026-35782-1
