01Si
SiliconOpaque. Rigid. Heat intensive.
Wafer silicon is proven and durable, but its conventional format cannot turn a transparent window into a generating surface.
Integration limitsTHE MATERIAL BEHIND INVISIBLE SOLARA new chemistry.
A new chemistry.
A new possibility.
Antimony chalcogenide thin films, engineered for the surfaces around us.
Explore the materialSb₂(S,Se)₃ Patented technology
WHY DO WE NEED A NEW SOLAR MATERIAL?Every solar material
Every solar material
has its limits.
02CdTe
Cadmium tellurideRare tellurium. Cadmium chemistry.
A successful thin-film technology built around scarce tellurium and a cadmium-containing absorber. Supply and end-of-life recovery matter.
Scarcity + material safety03CIGS
Copper indium gallium selenideComplex chemistry. Concentrated supply.
Four-element composition requires tight process control. Indium and gallium supply is concentrated in China, creating geopolitical exposure.
Composition + critical minerals04Perovskites
Lead-halide perovskitesHigh efficiency. Intrinsic instability.
Heat, moisture and light can destabilise the absorber; mobile ions add another degradation pathway. Lead creates a separate containment challenge.
Stability + leadTHE STABILITY QUESTIONStability should start
Stability should start
with the chemistry.
Lead-halide perovskites face fundamental chemical and ionic stability challenges. Encapsulation protects a device; it does not remove the absorber’s underlying degradation mechanisms.
Our platform starts with an intrinsically stable, inorganic antimony chalcogenide absorber. Device design and encapsulation then build on that foundation.
01 / THE MATERIAL ADVANTAGEWhat makes antimony
What makes antimony
chalcogenide unique?
Sb₂(S,Se)₃
Absorb energy.
Let light through.
Powerful absorption.
Very high visible-light absorption lets an exceptionally thin film capture energy.
Reported absorption coefficientUltra-thin. Light transmitting.
Reducing absorber thickness lets more light pass through. Thickness, composition and electrodes shape transparency.
A tunable optical balanceOne-dimensional ribbons.
Oriented crystal ribbons can span the film thickness, giving carriers direct pathways with benign grain boundaries.
Single-crystal-like transport pathsSimple. Defect tolerant.
Sb₂S₃ and Sb₂Se₃ offer simple chemistry. Their ribbon structure can tolerate grain boundaries.
Alloyed as Sb₂(S,Se)₃02 / LOWER-TOXICITY ABSORBER CHEMISTRYClean energy.
Clean energy.
Consider the chemistry.
82PbLead
Damage that can last.
Lead exposure can cause irreversible neurological harm, especially in children. Lead-containing absorbers require containment and recovery.
WHO · Lead exposure48CdCadmium
A persistent toxic metal.
Cadmium can damage kidneys, bones and the respiratory system. It is a human carcinogen; exposure prevention and end-of-life control are essential.
WHO · Cadmium exposureNo lead.
No cadmium.
Antimony chalcogenide provides a lower-toxicity absorber pathway without Pb or Cd in its composition.
Sb₂(S,Se)₃
03 / AUSTRALIAN SUPPLY PATHWAYGigawatts of potential.
Gigawatts of potential.
A fraction of one mine.
Antimony occurs naturally in stibnite. Australian production offers a local starting point for a resilient supply pathway, with refined precursors engineered into our thin-film absorber. Our platform avoids the tellurium used in CdTe and the gallium used in CIGS — pairing small material demand with an Australian route to scale.
~0.5%
of one Australian mine’s 2024 antimony output
for 1 GW of modules.
6.5 tAntimony per GW
1,282 tCosterfield output · 2024
Illustrative material calculation: 200 nm absorber, 10% module efficiency and 0.65 g antimony/m².
Mine production source · 2024~200×
more abundant.
Antimony is approximately 200 times more abundant than tellurium in Earth’s crust.
Antimony · 0.2 ppm
Tellurium · 0.001 ppm
Crustal abundance, not a measure of refined supply.
CRITICAL MINERALS / GEOPOLITICAL CONSTRAINTSWhen supply concentrates,
When supply concentrates,
risk travels.
CHINAShare of global production · 2024
99%Ga
Gallium
Primary production
Used in CIGS absorbers70%In
Indium
Refined production
Used in CIGS absorbers76%Te
Tellurium
Refined production
Used in CdTe absorbers04 / TUNABLE OPTICSHow can solar
How can solar
become invisible?
Changing the sulphur-to-selenium ratio tunes the bandgap across approximately 1.1–1.7 eV. Film thickness and the device stack then determine the balance between light absorption and transmission.
That flexibility opens a route to semitransparent, bifacial and tandem devices.
Read the optical researchEXPLORE THE ABSORPTION EDGE1.40 eV
Approximate cutoff · 886 nm
VisibleNear infrared
Se-rich · 1.1 eVS-rich · 1.7 eV
05 / MANUFACTURING WITH LESSLess heat.
Less heat.
A simpler growth route.
CONVENTIONAL PROCESSING ROUTES
Vacuum.
High temperature.
Vacuum infrastructure High thermal demand
Vacuum deposition and high-temperature stages are common in established solar manufacturing, adding equipment and energy demands.
SYDSOL ABSORBER GROWTH
Solution.
Low temperature.
Solution-grown absorber Lower-temperature growth
Grow the light-harvesting layer from a chemical solution, using a low-temperature hydrothermal route rather than vacuum absorber deposition.
Less thermal demandLower-cost potentialLower embodied-carbon potential
Solution-growth research · Nature Energy06 / PEER-REVIEWED FOUNDATIONPublished science.
Published science.
Protected innovation.
Nature Energy · 2026
Record-setting antimony chalcogenide devices
Chen Qian and colleagues improve hydrothermal growth, achieving 11.02% measured and 10.7% certified efficiency.
Advanced Materials · 2023Bifacial and semitransparent photovoltaics
Chen Qian and colleagues demonstrate light collection from both sides.
Journal of Materials Chemistry A · 20229.6% efficiency with an MnS hole-transport layer
Chen Qian and colleagues demonstrate all-inorganic Sb₂(S,Se)₃ solar cells using an MnS hole-transport layer.
PATENTED PLATFORM
Turning materials research into a technology platform for integration and licensing.
Discuss a technology partnership