Organic hole transport materials (HTMs) are critical for achieving high-efficiency and stable p-i-n perovskite solar cells, enabling efficient charge extraction and device performance exceeding 20% power conversion efficiency. At CSIR-NIIST, cost- effective, solution-processable carbazole and triphenylamine-based HTMs are being developed to advance scalable and flexible perovskite photovoltaic technologies.

Unique Features:
o Development of SAM and cross-linkable small-molecule HTMs for inverted PSCs
o Tunable energy levels for optimal band alignment and reduced recombination
o High hole mobility with excellent film-forming and stability characteristics
o Library of 50+ new HTMs enabling structure-property-performance optimization
o Solution-processable materials for flexible, large-area and low-temperature PSC fabrication 

Organic electrochromic materials based on triphenylamine and carbazole derivatives offer promising solutions for smart windows and energy-efficient optoelectronic devices due to their tunable optical properties, low operating voltage, and solution processability. At CSIR-NIIST, cross-linkable small-molecule systems are being developed to achieve durable, high-performance electrochromic films and scalable large-area smart window technologies.

 

Unique Features:
o Development of cross-linkable D-π-D organic electrochromic materials
o Hyper-cross-linking enables stable, solvent-resistant, and uniform EC films
o Enhanced coloration efficiency, optical contrast, and switching stability
o Improved charge transport and ion diffusion via controlled film morphology
o Scalable materials and device architectures for large-area smart window applications

o Achieved high external quantum efficiency among lead-free halide perovskite photodetectors through systematic organic cation engineering of bismuth iodide material.
o Demonstrated ultra-low voltage operation (sub-0.1 V) in bismuth halide perovskite photodetectors with sub-picoampere dark currents, among the lowest reported for this class of materials.
o Established inter-octahedral halide–halide contact distance as a quantitative design parameter for predictive materials engineering in low-dimensional hybrid perovskites.
o Demonstrated temperature-driven reversible p-to-n Seebeck polarity switching in single-walled carbon nanotube films without external voltage or polymer matrices, enabling autonomous adaptive thermoelectric operation.
o Developed flexible thermoelectric generators based on conjugated polymer–carbon nanotube composites with demonstrated waste heat harvesting from curved and body-heat sources, with operational stability exceeding hundreds of hours.
o Transferred process know-how for indigenous invisible fluorescent dyes and pigments for security printing to industry (HueBright Colors Pvt. Ltd., Bangalore), addressing a critical national need in anti-counterfeiting.

Harnessing the natural wealth (plant/herbal/microbial) of the region to obtain novel biologically active compounds or leads for drug synthesis, exploring traditional systems of medicine including Ayurveda, Siddha and tribal medicine for lead structures and correlating/corroborating this wealth of knowledge with modern diagnostic chemical and biological testing methods. The natural products isolated from plants/microbial cultures are screened against several biological targets for antibacterial, antiviral, anti-inflammatory activities. This is done through interdisciplinary collaborations within the institute and also with several national laboratories and universities. In addition, we have a very good facility for in vivo screening of molecules with biological potential. The abundant natural products are synthetically modified for enhancement of biological activity. By utilizing the rich repository of phytomolecules, we are supporting the quality control/standardization of herbal raw materials and finished products for Ayurveda and herbal industry. The scientific validation of herbal formulations, both classical and proprietary products are taken up in the institute. We have established a facility for herbal formulations with special focus on making galenical formulations of traditional medicines.

Unique Features:
o Methodological explorations for effective evaluation and validation of traditional wisdom
o Exploration of the medicinal plants and microbes of the Western Ghats
o Large repository of phytomolecules and analogues
o Skill and expertise for isolation and characterization of natural products
o Semisynthetic modification of natural products
o Multi-disciplinary and multi-institutional projects in CNS disorders and infectious diseases

The quest for sustainable development in chemistry has tempted both organic chemists and environmental chemists to search for green and environmentally friendly methodologies. For sustainable development, the methodologies should address three main factors: 1) reduced consumption of raw materials and energy, 2) maximum use of renewable resources and 3) minimal use of harmful chemicals. These new methods must be environment friendly with minimum of waste, with high efficiency and by utilizing processes with 100 % atom economy. There is an increasing demands for product safety and efficacy in the chemical industry and allied branches and this trend is evident in other branches of industry as well, due to increasing concerns for biodegradability of the products. The development of efficient methods to access complex molecules with multiple stereogenic centers has become a substantial challenge in both academic research and industrial applications. The growing importance of the chemical industry and other branches as part of Make in India initiatives of Government of India and the growing needs of effective, environmentally sound production methods, we are focusing developing sustainable methods by developing novel and efficient green routes for chemical synthesis.

Unique Features:
o Sustainable synthetic routes towards scaffolds for medicinal and material interests
o Green chemistry routes for chemical intermediates, agrochemicals and advanced pharmaceutical ingredients
o Organic photochemistry methodologies for green synthesis

Medicinal plants have demonstrated their potential as a repository of bio-active molecules with promising therapeutic potential and represent an important pool for the identification of novel drug leads. To investigate new phytochemical entities (NPCEs), naturally occurring phytomolecules are subjected to semi-synthetic modification, transforming them into pharmacologically active NPCEs that serve as lead candidates for clinical translation. In-depth investigations underlying molecular mechanisms were ruled out using detailed in vitro and in silico approach. In the area of chemical biology, an interdisciplinary team is investigating the intrinsic complexities of cell-surface glycans that impede to track the metabolic changes in cells. Metabolic glycan labelling (MGL) on the cell surfaces plays a pivotal role in cellular recognition like cell–cell communication and host–pathogen interactions etc. Moreover, fundamental structural changes have been observed in the course of many physiological processes which leads to the development of disease (e.g., cancer) progression.

Unique Features:
o Semi-synthetic modification of bioactive natural products isolated from plants
o New Phytochemical Entities (NPCEs) as advanced Hits / Leads towards anti-cancer, anti-inflammatory, anti-diabetic and antiviral potential

The team working on process development has successfully established different technologies for synthesizing active pharmaceutical ingredients (Nitazoxanide, Galidesivir, Molnupiravir and EIDD 1931), fluorescent dyes (red, blue, green and yellow) for security applications and agrochemicals (Flonicamid and spirotetramat). We focus on developing processes that utilize indigenous raw materials that are readily available. Another important factor that we take care of is the reduction in the number of process steps and also avoiding purification by column chromatography, thereby decreasing the cost of production.

Unique Features:
o Scalable processes utilizing easily available raw materials
o Reduction in process steps and production cost
o High yielding steps that doesn’t require expensive purifications

This research focuses on the rational design and synthesis of lead-free hybrid halide perovskites, where the judicious choice of organic spacer cations serves as the primary lever for tuning crystal structure, electronic dimensionality, and photophysical properties. Through systematic variation of organic ammonium cations spanning polarizable aromatic and π-conjugated derivatives, clear structure–property correlations have been established linking octahedral connectivity, quantum and dielectric confinement, and charge-carrier dynamics. A key finding is that the inter-octahedral halide–halide contact distance is a master structural parameter whose precise control through organic cation engineering progressively enhances electronic coupling between the inorganic units, narrows the optical bandgap, and facilitates exciton dissociation into free carriers. Flash-photolysis time-resolved microwave conductivity measurements directly probe photogenerated carrier dynamics, revealing that organic–inorganic heterojunction alignment dramatically extends carrier lifetimes beyond benchmark lead halide perovskites. This molecular engineering framework, grounded in crystal chemistry and photophysics, provides actionable design rules for developing high-performance, environmentally benign halide perovskite light absorbers.

This research investigates the thermoelectric properties of conjugated polymer–carbon nanotube composites and small-molecule organic semiconductors, with an emphasis on understanding how molecular structure governs charge transport, doping efficiency, and the Seebeck coefficient. By pairing donor–acceptor conjugated polymers with single-walled carbon nanotubes, polymer-mediated non-covalent interactions are exploited to tune Fermi-level alignment and interfacial charge transfer through molecular doping, significantly enhancing electrical conductivity and power factor. Complementary studies on self-assembled small molecules demonstrate how subtle structural modifications in end-group acceptor strength modulate charge transport and doping efficiency, underscoring the critical role of molecular design in organic thermoelectric optimization. Extending this chemistry to ionic thermoelectric systems, temperature-driven reversible Seebeck polarity switching through ion thermodiffusion has been demonstrated, enabling autonomous adaptive operation. These solution-processable, mechanically flexible materials are directly applied to harvesting low-grade waste heat from industrial, automotive, and human body sources, while their large thermoelectric response and room-temperature operability make them promising platforms for self-powered sensors in wearable and IoT applications.

Squalene is a linear polyunsaturated triterpene involved in sterol biosynthesis and valued for its antioxidant, biocompatible, and emollient properties. It has wide applications in food, pharmaceutical, nutraceutical, and cosmetic industries, including use as a vaccine adjuvant, drug delivery enhancer, and skincare ingredient. Conventional sources such as shark liver oil and plant oils face sustainability and cost limitations, prompting interest in microbial production. This study develops a metabolically engineered Pichia yeast model to enhance squalene synthesis by directing farnesyl diphosphate flux toward squalene while reducing ergosterol formation. Lipid droplet enhancement and fermentation optimization aim to improve yield for sustainable industrial-scale production.

Unique Features:
o Metabolic Flux Redirection: Enhances squalene production by channeling the precursor farnesyl diphosphate (FPP) specifically toward squalene synthesis while minimizing its conversion into ergosterol.
o Engineered Pichia Yeast Platform: Utilizes a genetically modified yeast system known for rapid growth, ease of genetic manipulation, and suitability for large-scale industrial fermentation.
o Sustainable and Scalable Production Strategy: Provides an eco-friendly alternative to animal- and plant-derived sources through optimized fermentation and process parameters for improved yield and industrial applicability.

Growing environmental concerns about petroleum-based plastics have accelerated the development of sustainable, biodegradable alternatives for packaging and hygiene applications. Poly-γ-glutamic acid (γ-PGA), a naturally derived, biodegradable, and biocompatible biopolymer produced through microbial fermentation, has gained significant attention due to its strong film-forming ability, moisture-retention capacity, and environmental safety. Fruit-processing wastes were used as renewable carbon sources for the fermentative production of γ-PGA, thereby promoting waste valorization within a circular bioeconomy framework. The synthesized biopolymer was used to fabricate γ-PGA composite films enhanced with active components, thereby developing active food packaging materials that improve the preservation of perishable fruits. Furthermore, γ-PGA was explored for the preparation of superabsorbent hydrogels suitable for hygiene applications, owing to its high water absorption and biodegradability. This work demonstrates an integrated approach toward sustainable material development from agro-industrial waste as an alternative to single-use plastics.

Unique Features:
o Sustainable production of poly-γ-glutamic acid (γ-PGA) using fruit processing waste as a renewable carbon source.
o Development of biodegradable chitosan–γ-PGA composite films for active food packaging with enhanced functional properties.
o Fabrication of superabsorbent γ-PGA hydrogels for potential hygiene applications.
o Integrated waste valorization approach offering eco-friendly alternatives to conventional single-use plastics.