Speaking with TechGraph, Gadhadar Reddy, Co-Founder and CEO of NoPo Nanotechnologies, discussed how manufacturing complexity, low yields, and purification challenges kept single-walled carbon nanotubes from achieving large-scale commercial adoption for decades, and how growing demand from batteries, semiconductors, and filtration applications is driving the need for scalable production technologies that can support industrial use.
Reddy also discussed how NoPo Nanotechnologies has refined its proprietary HiPCO process to improve production consistency and scalability, allowing customers to deploy SWCNTs across applications such as advanced batteries and semiconductor manufacturing while addressing longstanding challenges associated with commercial production.
Read the interview in detail:
TechGraph: Single-walled carbon nanotubes have been studied for decades and have consistently shown strong theoretical potential across multiple industries. Yet large-scale commercialisation has remained limited to a small number of players globally. What, in your view, were the fundamental bottlenecks that kept the category from scaling earlier, and what has changed now that allows companies like NoPo Nanotechnologies to move towards more confident industrial production?
Gadhadar Reddy: The historical bottleneck was the manufacturing chemistry, not the material’s promise. SWCNT synthesis sits in a narrow thermodynamic window — any deviation produces multi-walled tubes, amorphous carbon, or catalyst residue rather than the single-walled material customers need.
Three constraints kept the category from scaling. First, substrate-based chemical vapour deposition — the dominant laboratory route — is a batch process: load, react, harvest, repeat. The harvesting step damages the tubes and introduces contamination, and the economics do not close at industrial volumes. Second, the cleaner alternatives — arc discharge and laser ablation — produced yields so low they remained laboratory curiosities. Third, purification was historically treated as a downstream afterthought rather than a co-designed parameter.
What has changed is a combination of demand pull and process maturation. Gigafactory-scale battery production, sub-3 nm semiconductor nodes, and ESG-driven filtration mandates are creating sustained technical demand that earlier markets could not. On the supply side, the High-Pressure Carbon Monoxide (HiPCO) route has been engineered as a continuous gas-phase process, with downstream purification co-designed to the output. At NoPo, roughly 15 years of reactor refinement has increased output by approximately 300X from our initial configuration. The material that comes off the reactor in month six matches what came off in month one.
TechGraph: How does your proprietary HiPCO process differentiate itself from conventional nanotube manufacturing methods in terms of measurable advantages?
Gadhadar Reddy: HiPCO is one of four principal SWCNT synthesis routes — alongside arc discharge, laser ablation, and substrate-based CVD — and the differences are structural rather than incremental. In HiPCO, carbon monoxide gas at 30–50 atmospheres and 900–1100 °C undergoes Boudouard disproportionation over iron catalyst clusters formed in situ from iron pentacarbonyl decomposition.
Three engineering attributes follow. First, the process is all-gas-phase and continuous — no substrate, no batch loading, no harvesting step. Scaling becomes a reactor-engineering problem rather than a substrate-throughput problem, and the material exiting the reactor today matches what will exit months later. For customers moving an application from R&D to commercial scale, that batch-to-batch stability is the variable that actually matters during qualification.
Second, CO is a single carbon source — unlike hydrocarbon-based CVD routes, which co-produce amorphous carbon that has to be removed downstream and which damages the tubes in cleanup.
Third, the HiPCO thermodynamic window naturally favours small diameters (0.6–1.2 nm) and a relatively narrow chirality distribution. Smaller diameters give higher conductivity, which matters for battery and ESD/EMI shielding applications.
TechGraph: In materials like SWCNTs, performance is not just a function of purity but also of how precisely structural characteristics such as chirality, diameter, and dispersion are controlled. When moving from lab-scale precision to industrial-scale manufacturing, where do these variables typically become difficult to manage, and how do you approach maintaining that level of consistency?
Gadhadar Reddy: Each of these three variables fails at a different boundary, and they cannot be addressed with a single intervention.
Diameter distribution is set at synthesis by catalyst nanoparticle size and the local thermodynamic environment, which depend on simultaneous control of pressure, temperature gradient, CO flow, and iron pentacarbonyl feed. The challenge at industrial scale is sustaining those tolerances across a larger reactor volume, where temperature gradients lengthen, and flow regimes become turbulent. NoPo’s reactor is designed in-house, with over 90% of components sourced within India; the parameter window that keeps the diameter distribution narrow is a function of that specific geometry, refined over fifteen years.
Chirality is the harder problem and the one the industry has not yet solved at production scale. SWCNTs produced from reactors have a mix of different chiralities. For semiconductor channel-material applications, where band gap depends on chirality, the industry requires single-chirality material — currently a laboratory-scale process based on techniques such as density-gradient ultracentrifugation or selective polymer wrapping. NoPo has demonstrated single-chiral material at lab scale and is working on the scale-up; we do not claim industrial single-chirality supply today, and any producer who does should be examined carefully.
Dispersion is a downstream problem, not a synthesis problem. Strong van der Waals attraction makes as-produced powder form tight bundles that resist incorporation into liquids and matrices. The applications-engineering work — surface functionalisation, surfactant systems, polymer-wrapped derivatives — is what makes raw SWCNT usable in a customer’s slurry, ink, or composite, and is where much of the value gets captured.
TechGraph: In sectors such as batteries and energy storage, performance improvements are often incremental and highly optimised over time. Within that context, where do SWCNTs deliver a clear and meaningful advantage over existing materials, and where do they still struggle to justify widespread adoption?
Gadhadar Reddy: In batteries, SWCNTs are most clearly justified where the alternative is mechanical failure rather than incremental performance loss. The clearest case is the silicon-rich anode. Silicon stores roughly ten times more lithium per unit mass than graphite, but it expands approximately 300% during lithiation and contracts on discharge.
Conventional carbon-black additives, being roughly spherical, lose electrical contact with the active material after tens of cycles, and the cell fails. SWCNTs — long, flexible filaments — form a conductive network that flexes with the expansion rather than fracturing. Reported cycle-life improvements on silicon-rich anodes using SWCNT conductive additives are on the order of 4X relative to conventional alternatives, at loadings under 0.1 wt%.
The second case is the solid-state interface, where active particles move under cycling, but the surrounding matrix is rigid; maintaining contact across moving interfaces is something point-contact additives cannot do, but line-contact additives can. The same logic extends to lithium-sulfur.
Widespread adoption is a matter of timing. New cell design takes years to develop and get adopted in mass-scale production. SWCNT loaded Silicon anodes are already being commercially used across EV and other batteries, it is a matter of time when they will have a sizeable share of the market.
TechGraph: Globally, advanced materials manufacturing remains concentrated among a small group of players with deep research and capital backing. From your perspective, what does it take for an India-based company like NoPo Nanotechnologies to compete at that level, both in terms of technical credibility and commercial trust?
Gadhadar Reddy: Technical credibility for a deep-tech materials company is established through three measurable outputs: published characterisation matched by third-party measurement, qualification by customers whose own processes are technically demanding, and patent prosecution that survives prior-art examination.
NoPo has approximately fifteen years of HiPCO process development behind it, five patents filed across synthesis, purification, and functionalisation, and material that has been qualified by ISRO for space-grade applications. The company is ISO 9001 certified. The case is made by the datasheet and the qualification report; it is not made by claims.
Commercial trust is more structural. For a global customer to qualify an alternative supplier, three conditions must be met: the material must match or exceed the incumbent’s specification; the supply chain must be auditable and resilient; and the supplier must demonstrate the financial and operational capacity to honour multi-year offtake. Characterisation work has shown parity or advantage for NoPo’s material on conductivity — a direct consequence of our smaller diameters.
Our supply chain is approximately 90% sourced within India for reactor components and 100% for feedstock. The 2024 pre-Series A round of USD 3 million from Axilor’s Micelio Fund and Inflexor Ventures funds the capacity expansion required to support committed offtake.
TechGraph: As demand grows across electronics, energy systems, and mobility, materials are increasingly becoming a source of competitive advantage rather than just a component. Where do you see SWCNTs becoming indispensable in the near future rather than remaining an optional performance enhancer?
Gadhadar Reddy: A material becomes indispensable when its absence breaks the application rather than merely degrades it. Silicon-rich battery anodes are one such application. The premise of moving from graphite to silicon-graphite composite anodes — the basis of most next-generation EV cell roadmaps — depends on a flexible conductive network that survives 300% volume change. SWCNTs are the commercially available material that delivers this at sub-0.1 wt% loading.
For EMI shielding and ESD properties, SWCNTs play a critical role where all other materials fail in composite materials, flooring, coatings, and other applications. The traditional materials used are typically steel or copper, resulting in high installation and maintenance costs, weight, and reliance on high-emission metals.
TechGraph: Looking ahead, as the category continues to evolve, do you see the next phase of growth being driven more by breakthroughs in new applications, or by the ability to industrialise production in a way that makes SWCNTs more accessible at scale?
Gadhadar Reddy: The applications moving from prototype to volume production during this window (silicon anodes, conductive additives for cathodes, ESD composites, solid-state cell components, conductive coatings and inks) are not new applications. They are existing applications bottlenecked by inconsistent supply, unstable specifications, and concentration of production with a single dominant producer. As trusted alternative supply comes online at scale — NoPo and one or two other producers globally crossing from kilogram-scale to ton-scale production — these applications will exit qualification and enter serial production.
The subsequent phase — over ten to twenty years — will then be driven by genuinely new applications that industrialised supply makes possible: single-chirality SWCNT transistors at semiconductor production volume, SWCNT-reinforced thermal protection for hypersonic vehicles, SWCNT membranes for municipal-scale water filtration, quantum-sensor materials. These are real applications, but they presuppose a supply base that does not yet exist.