An IIT Guwahati research team has developed a new technology using perovskite semiconductor material, achieving 25.73% solar cell efficiency and creating stable memristor devices for next-generation memory and neuromorphic computing.
A research team at the Indian Institute of Technology Guwahati has developed a new technology on perovskite semiconductor material, known for its potential applications in solar cells and resistive-switching (memristor/R-RAM) devices. Perovskites are a class of materials with a distinctive crystal structure that enables strong light absorption and efficient charge separation for high-performance solar cells, while their defect-tolerant electronic properties and ion migration behaviour make them highly promising for memristor devices.
Addressing Perovskite Instability Challenges
Perovskite solar cells comprise multiple functional layers, where photogenerated charge carriers are extracted through selective transport layers to generate electricity. However, losses at interfaces arising from surface defects, chemical redox reactions and energy-level mismatches lead to charge trapping and recombination. These challenges are further intensified under environmental stress, such as moisture, heat and oxygen, resulting in degradation and reduced operational stability, thereby limiting the practical use of perovskites in real-world scenarios.
However, the resistive switching behaviour of perovskite memristors is often affected by uncontrolled ion migration, defect-assisted conduction, and interfacial instabilities, leading to variability in switching parameters. These issues result in poor switching uniformity, limited endurance, retention degradation, and an incomplete understanding of the underlying switching mechanism, thereby hindering the development of reliable perovskite-based memory devices for future neuromorphic computing and next-generation non-volatile memory applications.
A Novel Molecular Interface Engineering Method
To address these limitations, Prof. Parameswar K. Iyer, Professor, Department of Chemistry and Centre for Nanotechnology, along with his research team, developed a molecular interface engineering method using two specially designed bright donor-acceptor organic molecules. These strategic organic compounds are deposited as 10-15 nm ultrathin layers (a hundred thousand times thinner than a human hair) between the charge-transport layer and the perovskite layer as part of the device engineering tactic. These organic molecules control how electrical charges behave at the interface and reduce defects, resulting in the easy and smooth flow of charges created by sunlight across the interface.
Enhanced Solar Cell Performance
This approach enabled solar cells to achieve an efficiency of 25.73%, corresponding to the conversion of nearly one-quarter of incident sunlight into electricity, which is highly competitive among state-of-the-art devices of this class.
The research team also found that the interfacial engineering approach retained approximately 90% of its initial performance after prolonged storage under ambient conditions and about 75% under continuous thermal and light stress, highlighting the robustness of the developed materials.
Multifunctional Memristor Potential
Beyond solar cells, the team demonstrated that the same (FA-based) perovskite material can be integrated into memristor devices using a thin 220-nm-active layer, showcasing its multifunctional potential. These devices exhibit stable low-power switching, multistate memory performance, and reliable endurance, making them promising candidates for next-generation memory and crossbar arrays for neuromorphic computing. The study also provides important insights into the switching mechanism governed by defect states and ion migration. Furthermore, the multistate memory behaviour highlights its potential for neuromorphic computing and artificial intelligence hardware. The stochastic formation of conductive filaments also enables true random number generation, offering promising opportunities for secure computing, cryptographic systems, and next-generation intelligent electronic technologies.
Future Applications and Commercialization
Speaking about the real-world usage of the developed materials, Prof. Parameswar K. Iyer, Professor, Department of Chemistry, IIT Guwahati, said, “This work demonstrates the potential of perovskite-based semiconductor technologies for next-generation solar cells and memory devices. The synthesised novel organic molecules enable improved interfacial engineering for highly efficient and stable solar energy conversion, while the same material platform exhibits reliable resistive switching for advanced memory and neuromorphic computing applications. Such advances could accelerate the large-scale commercialisation of integrated optoelectronic systems combining energy harvesting, information storage, and intelligent computing within a single technological framework.”
In addition to the development of low-cost and efficient solar cells and memory devices, these improved perovskite systems can also support energy-efficient computing approaches, such as neuromorphic systems, which emulate how the brain processes information using networks that mimic neurons and synapses. Their thin-film nature is also well-suited for flexible electronics and integrated devices that combine energy generation and data storage.
The findings of this research have led to multiple patent filings for perovskite solar cell technology, memory devices and the publication of two separate high-impact research articles recently in the prestigious international journal ‘Advanced Functional Materials’ (Wiley) co-authored by Prof. Iyer along with his research team, including Ramkrishna Das Adhikari, Himangshu Baishya, Mizanur Alam, Manab Kalita, Mayur Jagdishbhai Patel, Deepak Yadav, Diganta Bhattacharyya, Priyam Ghosh, in collaboration with Swastik Laha, and Dr. Kalishankar Bhattacharyya from IIT Guwahati.
This work is funded by the Department of Science and Technology, New Delhi, Integrated Clean Energy Material Acceleration Platform on Materials (IC-MAP) (DST/TMD/IC-MAP/2K20/03).
As the next step, the research team has made progress and achieved beyond 26 % solar cell efficiency and further aims to improve the developed materials’ performance in large area real-world conditions over longer periods. The team is also working with an industry partner on developing methods to scale up its fabrication for larger areas and flexible devices for commercial applications.
As research in advanced materials continues to progress, this advancement by the IIT Guwahati research group bridges a major gap between functional materials development at the laboratory, theoretical insights and real-world implementation in space technologies for powering satellites and space missions by enabling lightweight flexible energy conversion devices, stability against cosmic radiation in extraterrestrial conditions. (ANI)
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