A P3HT-Stabilised Spiro-OMeTAD Composite Hole Transport Material for High-Performance Perovskite Optoelectronic Devices

Siddhant Singh^a, Abhishek K. Chauhan^b, Swapnil Barthwal^c, Ranju dalal^a, Akila G. Prabhudessai^a, Akshay Singh^a, Ramesh Karuppannan^a

^aDepartment of Physics, Indian Institute of Science, Bengaluru-560012, Karnataka, India.

^bCHOSE (Centre for Hybrid and Organic Solar Energy), University of Rome Tor Ver gata, Italy.

^cDepartment of Chemistry and Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan-5290002, Israel

Materials for Sustainable Development Conference (MATSUS)
Proceedings of MATSUS Fall 2026 Conference (MATSUSFall26)

D2 Functional Materials for Emerging Photovoltaics: from Everyday Integration to Extreme Environments

Palma, Spain, 2026 October 26th - 30th

Organizers: Jessica Barichello, Stefania Cacovich and Fabio Matteocci

Poster, Siddhant Singh, 534
Publication date: 22nd July 2026

The advancement of perovskite optoelectronics is closely tied to the development of robust charge‑transport layers. While Spiro‑OMeTAD remains the benchmark hole‑transport material (HTM), its practical application is limited by stability issues inherent to chemical doping. This work explores a composite approach to enhance Spiro‑OMeTAD in triple‑cation perovskite solar cells (TC‑PSCs) by incorporating a low concentration of P3HT as a stabilising agent. The optimal composition (Spiro‑OMeTAD_{_0.94} :P3HT_{_0.06} , P6) synergistically combines favourable energetics with the hydrophobic nature and morphological compatibility of P3HT, leading to improved interfacial coverage and stability. In PSCs, the P6 composite achieves a PCE of 20.7%, outperforming pristine Spiro‑OMeTAD through enhanced hole extraction and reduced carrier lifetimes. Supporting analyses, including SCLC, EIS, and EQE, which confirm improved mobility, charge transport, and photocurrent generation, while MPPT validates stable operational output. The composite strategy also extends to photodetectors, where self‑powered devices exhibit responsivity gains of 46% (532 nm) and 24% (655 nm), with detectivities up to 3.8 × 10¹² Jones. Moreover, the P6 composite confers exceptional moisture resistance, suppressing δ‑phase evolution under 80% ± 5% RH and enabling unencapsulated devices to retain over 80% of their initial efficiency for 920 hours. This composite HTM architecture offers a scalable pathway to stable, high‑performance perovskite optoelectronics.

References:

[1] (1)Singh, S.; Chauhan, A. K.; Barthwal, S.; Dalal, R.; Prabhudessai, A. G.; Singh, A.; Ramesh, K. A P3HT-Stabilised Spiro-OMeTAD Composite Hole Transport Material for High-Performance Perovskite Optoelectronic Devices. Solar Energy Materials and Solar Cells 2026, 308, 114696. https://doi.org/10.1016/j.solmat.2026.114696.

Acknowledgements:

We acknowledge support from CeNSE facilities funded by MHRD, MeitY, and DST India. We thank the Indian Science Technology and Engineering facilities Map (I-STEM), a program supported by the Office of the Principal Scientific Advisor to the Govt. of India, for enabling access to the X-ray diffractometer (Smart Lab-Rigaku), Confocal Photoluminescence Raman Spectro Microscope (WITec Alpha 300R) and time-resolved fluorescence microscope (PicoQuant-MicroTime 200) at the Department of Physics, Indian Institute of Science, Bangalore, to carry out this work.

nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.

MATSUS

Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.

International Conference on Hybrid and Organic Photovoltaics

International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.

Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics

The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.

International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics

The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.