IIT Bombay Engineers a Cobalt-Nickel Catalyst That Could Cut Green Hydrogen's Platinum Problem

A catalyst problem hiding inside India's hydrogen ambitions

India wants gigawatts of electrolysers splitting water into hydrogen and oxygen, but the reaction at the heart of that plan has long depended on platinum and iridium — two of the rarest, costliest metals on the planet. A new paper out of IIT Bombay this month suggests a workaround: swap the noble metals for cobalt, nickel and ordinary graphite, arranged in a way that turns out to work almost as well.

Researchers Savi Chaudhary and Prof. Ramaswamy Murugavel, in the Department of Chemistry at IIT Bombay, have engineered an amorphous cobalt-nickel phosphate catalyst anchored onto exfoliated graphite — flakes of graphite pried apart to expose more surface area. The work, titled "Engineering Amorphous Cobalt–Nickel Phosphate Nanostructures on Exfoliated Graphite: A Molecular Precursor-Driven Route to High-Performance Alkaline Water Splitting Catalysts," was published in the Wiley journal Small.

Why the metal matters

Water electrolysis — using electricity to split H₂O into hydrogen and oxygen — is the backbone of "green" hydrogen production when the electricity comes from renewables. But the reaction has two halves: the hydrogen evolution reaction (HER) at the cathode and the oxygen evolution reaction (OER) at the anode. OER in particular is sluggish and energy-hungry, and the catalysts that speed it up efficiently — platinum, iridium oxide, ruthenium oxide — are scarce and expensive enough that they are a real bottleneck for scaling electrolysers to gigawatt levels.

That has pushed materials scientists worldwide toward earth-abundant alternatives: transition metals like cobalt, nickel, iron and manganese, often paired with phosphates, sulphides or nitrides to boost their catalytic activity. The IIT Bombay team's contribution is a synthesis method — a "low-temperature molecular precursor strategy" — that grows amorphous (non-crystalline) cobalt-nickel phosphate nanostructures directly onto graphite that has been exfoliated to maximise surface area. The result is a catalyst active enough to run both halves of the water-splitting reaction: it works at the cathode for hydrogen evolution and at the anode for oxygen evolution, a rarer "bifunctional" property that simplifies electrolyser design because a single material class can do both jobs instead of needing separate catalysts on each electrode.

What the numbers say

According to the published results, the catalyst drives overall water splitting at a cell voltage of 1.70 V in a two-electrode alkaline configuration, with stability holding up over 72 hours of continuous testing. For context, the theoretical minimum voltage to split water is about 1.23 V; real-world electrolysers typically run in the 1.8–2.0 V range because of the energy losses (overpotential) that catalysts exist to minimise. A cell voltage of 1.70 V places this material competitively close to systems built around precious-metal catalysts, while using only cobalt, nickel, phosphate and graphite — all far cheaper and more abundant than platinum-group metals.

The graphite substrate does double duty. Beyond simply hosting the catalytic nanostructures, exfoliating it increases conductivity and surface area, which helps more of the active cobalt-nickel phosphate sites stay electrochemically accessible during the reaction — a common failure point for non-precious-metal catalysts, which can lose activity as nanostructures aggregate or detach from a poorly conducting support.

Where this fits in India's hydrogen push

The Union government's National Green Hydrogen Mission has been pushing on two fronts simultaneously: subsidising deployment (electrolyser manufacturing incentives, hydrogen mobility pilots, an "electrolyser-as-a-service" leasing model announced this year) and funding the underlying materials science that determines how efficient — and how expensive — that deployment ends up being. Import dependence on platinum-group catalysts is a recognised cost driver for Indian electrolyser manufacturers, most of whom currently license or import stack designs rather than engineer catalysts domestically.

Academic results like this one are a long way from a commercial electrolyser stack — the paper describes lab-scale testing, not a pilot plant, and questions like manufacturability at scale, catalyst durability over thousands of hours (rather than 72), and integration into existing alkaline or PEM electrolyser architectures remain open. But the direction is one that both government mission planners and electrolyser manufacturers have been watching closely: every rupee shaved off the catalyst bill of materials makes green hydrogen more competitive against grey (fossil-fuel-derived) hydrogen, which remains cheaper in most of India today.

IIT Bombay's chemistry department has an established track record in electrocatalysis research, and this paper adds to a broader body of Indian academic work — spanning IITs, IISc and CSIR labs — chasing non-precious-metal catalysts for exactly this reason: hydrogen's climate promise only pays off economically if the catalysts don't cost more than the metals they replace are supposed to save.

The gap between a paper and a plant

It is worth being precise about what has and hasn't been demonstrated. The Small paper reports catalyst performance under controlled laboratory conditions: a specific alkaline electrolyte, a two-electrode lab cell, and a 72-hour stability window. Commercial alkaline electrolysers need to run reliably for tens of thousands of hours, often with fluctuating power input from wind or solar rather than the steady current used in a lab test, and at electrode areas many times larger than a bench-scale sample — a jump in scale that has tripped up plenty of promising catalysts before this one. None of that is unusual for early-stage materials science; it is simply the long, unglamorous distance that separates a strong journal result from a bill of materials that an electrolyser manufacturer would actually adopt.

What makes results like this one worth tracking regardless is the direction of travel. Precious-metal catalyst cost is one of a handful of line items — alongside membrane cost, stack manufacturing and balance-of-plant equipment — that determine whether Indian-made electrolysers can compete on price with Chinese alkaline stacks, which currently dominate global cost benchmarks partly because of cheaper catalyst and manufacturing choices. A domestically engineered, non-precious-metal bifunctional catalyst, if it survives the scale-up gauntlet, would remove one of the few inputs India cannot currently produce cheaply at home. That is a narrower, slower-moving story than a funding round or a policy announcement, but it is the kind of incremental materials advance that green hydrogen's unit economics ultimately depend on.

Sources

• Chaudhary, S. & Murugavel, R., "Engineering Amorphous Cobalt–Nickel Phosphate Nanostructures on Exfoliated Graphite: A Molecular Precursor-Driven Route to High-Performance Alkaline Water Splitting Catalysts," Small, Wiley Online Library, 2026. https://onlinelibrary.wiley.com/doi/10.1002/smll.202508598
• Research Matters, "IIT Bombay researchers engineer an economic and efficient catalyst to split water molecules," August 2026. https://researchmatters.in/index.php/news/iit-bombay-researchers-engineer-economic-and-efficient-catalyst-split-water-molecules
• Chemical Industry Digest, "IIT Bombay Develops Breakthrough Catalyst for Efficient Green Hydrogen Production," August 21, 2026. https://chemindigest.com/iit-bombay-develops-breakthrough-catalyst-for-efficient-green-hydrogen-production/