Callinectes BrothersContact

Nanoscale photochemistry · Est. 2022

Green hydrogen,
split with light

Artificial photosynthesis takes a single hydrogen atom off a water molecule with light and a reusable catalyst — 40% less energy per kilogram than electrolysis, and nearly free under direct sun.

Partner with usHow it works

A round-bottomed flask of water on a violet LED panel, gas bubbling up its neckPlay: Hydrogen from water: proof of concept (opens on YouTube if scripting is unavailable)
Fig. 01 — Proof of concept, hydrogen off water

40%

Less energy per kilogram than electrolysis

2e⁻

Electron pathway, against electrolysis’ four

H₂O₂

Second product, self-separating from the gas

2022

Founded, bootstrapped, two founders

Section 01

Two electrons, not four

We split water with light instead of blasting it apart with current. The two-electron pathway finesses one hydrogen atom off the molecule; the parts recombine as hydrogen and hydrogen peroxide — a gas and a liquid, so they separate themselves.

Electrolysis, developed since the 1960s, uses a four-electron process to make hydrogen and oxygen, which must then be separated. Fifty percent or more of its cost per kilogram is the electricity itself — and if that electricity is not additional renewable capacity, the hydrogen is not green.

Read the technical FAQ →

Diagram, 'Photosynthesis for Green Hydrogen': salt or fresh H2O, plus sun or electric light, over a reusable catalyst, yields H2 + H2O2 — labelled low energy 2-electron water splitting, self separating.
Fig. 02 — The reaction
Slide, 'Value Proposition': Our technology makes green hydrogen production cheaper than electrolysis and energy-competitive with gray hydrogen produced by steam methane reformation. It also solves hydrogen transportation issues by enabling on-site production that scales up or down as necessary. Below, a cost bar runs from $1/kg for gas, coal, carbon capture, nuclear and natural sources up to $5/kg for hydro, wind and solar and 100% renewable sources; an arrow carries the $5/kg renewable end back down to $1/kg.
Fig. 03 — Cost per kilogram, against the incumbents

Section 02

Partnership

Announced 2026

University of Lisbon

Técnico Solar Boat

We are working with the student engineering team at Instituto Superior Técnico, whose solar-powered and hydrogen craft race on real water against real weather. It is the sharpest test bed we could ask for: on-site production, on-demand demand, and engineers who will tell us plainly when something does not work.

tecnicosolarboat.com ↗
A presenter at a podium beside Técnico Solar Boat's new hydrogen-powered catamaran on stage, a screen behind reading 'SM02'; the hull is lettered with event sponsor names including CalliBros.com, SunConcept Solar Boat Builders, and INCM SCT Power, 'Solving Challenges Together'.
Técnico Solar Boat unveils SM02, its new hydrogen-powered boat

Técnico Solar Boat unveils SM02, its new hydrogen-powered boat

Updates from the collaboration

LinkedIn postTécnico Solar Boat thanks Callibros for its supportLinkedIn postTécnico Solar Boat on green hydrogen for maritime propulsion

Section 03

Media

Films, bench footage and stills — the evidence, in one place.

01 / Films

Title card for the company overview video: the Callinectes Brothers crab wordmark over a green band reading 'Artificial photosynthesis for the production of green hydrogen,' with Bill Hitchcock and Rob Arnold named beneath it alongside their callibros.com email addresses, and a still of the lit reaction flask at the right.Play: Callinectes Brothers company overview (opens on YouTube if scripting is unavailable)
Company overview6 min · Updated Jan 8, 2024
A round-bottomed flask of water on a violet LED panel, gas bubbling up its neckPlay: Hydrogen from water: proof of concept (opens on YouTube if scripting is unavailable)
Proof of conceptShort · Hydrogen off water

02 / Bench footage

A stoppered glass bottle of cloudy liquid on a lab bench, backlit by a sunlit window.Sunlight
Sunlight water splitting0.1 g catalyst · direct sunlight
Close-up of a glass flask lit from below by a violet UV LED panel, bubbling.UV
UV water splitting0.1 g catalyst · UV light
A graduated flask of water bubbling on a violet UV LED panel in a darkened room, gas rising to the surface.Sea water
Sea water splitting0.5 g catalyst · untreated sea water

03 / Stills from the bench

A 500 mL Duran Erlenmeyer flask stoppered and wired into lab equipment, a white gas line running from its top and an electrode fitting threaded into its side, sitting on a bed of aluminum foil.
Reaction setup500 mL flask, wired and running
A hand holding a graduated 50 mL centrifuge tube, marked in 5 mL increments up to 45 mL, part filled with a cloudy solution.
Measuring a sampleGraduated tube, catalyst solution
A glass beaker of pale liquid on a lab bench beside a graduated tube and coiled tubing, next to an appliance carrying German and English safety warning labels.
Diluted sampleReady for the bench
Overhead view of two hands weighing a white powder on a small metal spatula over a beaker, beside an analytical balance in its glass draft shield.
Weighing the catalystOn the analytical balance

More videos are on the way.

Section 04

Licensing

By application and by region. The US and EU are the initial targets; other regions as the State Department allows.

Application areas by licensing region. A marked cell names an application under discussion in that region.
AreaUnited StatesEuropean UnionGlobal Areas
Industrial———
UtilityMicro-Grid *Energy Storage *Energy *—
Transportation———
Space Travel———
Military & defense———

* Potential early adopters with whom we are in discussion. Early partners steer our R&D toward their own customers — an exclusive club for the first few years, because we will not spread ourselves thin.

Section 05

Where we are headed

Applied Science

Phase One

  • Catalyst development
  • Proof of concept
  • Production economics
  • 3rd party analytical resultswe are here
  • Angel financing
  • Intellectual property
  • Partnerships

Pilot Scale

Phase Two

  • Catalyst production
  • Safety research and engineering
  • Fixed costs forecasting and planning
  • Pilot skids or plant
  • Green hydrogen market entry through partners

Scale Up

Phase Three

  • United States licensing
  • European Union licensing
  • Global licensing
  • Hydrogen peroxide applications
Slide, 'Roadmap': a winding road runs from bootstrap and catalyst development through 2023 (bubbles, dynamic reaction), 2024 (super bubbles and proof of concept, substrate bonding, energy cost, third-party analytics — marked Today), angel funding and first patents, on to 2026 (partners, pilots), 2032 (US and EU licensing, global licensing) and an exit. Catalyst development, bubbles, super bubbles, substrate bonding and energy cost are checked off.
Fig. 04 — The road, bootstrap to exit

Section 06

Help wanted

Where an introduction, an hour, or a hard question would move us forward.

People

  • Introductions to partners
  • Mentors

Expertise

  • Engineering & Safety
  • Business Development
  • Green hydrogen programs

Reach

  • United States
  • European Union
  • Capitalization
  • Competitors, know any?

Want to talk?

We are looking for partners, mentors, and the kind of question that makes us go back to the bench.

Contact usOur journey