Smoltek has devel­oped a porous trans­port elec­trode (PTE) that reduces the amount of irid­i­um cat­a­lysts in PEM elec­trolyz­ers to a min­i­mal 0.1 mg/​cm², thus reach­ing the lev­el that is con­sid­ered to make large-scale pro­duc­tion of PEM elec­trolyz­ers profitable.

0.1 mg irid­i­um per square cen­time­ter – a tech­no­log­i­cal breakthrough

We are the only ones to pro­duce hydro­gen with only 0.1 mg iridium/​cm² with­out com­pro­mis­ing cell per­for­mance. We have thus solved one of the hydro­gen indus­try’s biggest tech­ni­cal chal­lenges – the lim­it­ed avail­abil­i­ty of irid­i­um, which has so far been an obsta­cle to large-scale pro­duc­tion of PEM electrolyzers.

^{Elli­nor Ehrn­berg, Pres­i­dent of Smoltek Hydrogen}

In addi­tion to the lim­it­ed avail­abil­i­ty of the scarce pre­cious met­al (glob­al sup­ply only 9 tons/​year), the high costs of irid­i­um have also been a source of lim­it­ed invest­ment will­ing­ness for PEM electrolyzers.

250-hour dura­bil­i­ty shows same result as 1,000-hour test 2024
In a recent dura­bil­i­ty test over 250 hours of con­tin­u­ous oper­a­tion (at 2 A/​cm²), Smoltek Hydrogen’s PTE pro­duced hydro­gen with a cat­a­lyst load­ing of only 0.1 mg iridium/​cm² – with­out any degra­da­tion of the nanos­truc­ture of the elec­trolyz­er cell. The test results demon­strate that the company’s anode elec­trode tech­nol­o­gy is durable and effi­cient, while reduc­ing irid­i­um usage by 95 per­cent com­pared to con­ven­tion­al technology.

This test showed the same results as the 1,000-hour dura­bil­i­ty test we car­ried out in April 2024, but now with half the amount of irid­i­um. When we saw that the cell per­for­mance was equiv­a­lent at both 0.1 mg and 0.2 mg irid­i­um, we chose to dis­con­tin­ue the test and focus devel­op­ment on oth­er parts of the PTE tech­nol­o­gy for the next longer dura­bil­i­ty test.

^{Fabi­an Wenger, Head of R&D at Smoltek Hydrogen}

Smoltek’s PTE is mak­ing a mark in the hydro­gen indus­try
Smoltek Hydrogen’s nanos­truc­ture for PTE has been devel­oped in record time. The first pro­to­types with 0.5 mg iridium/​cm² began seri­ous test­ing in 2023. The results showed that fur­ther research into how Smoltek’s nanos­truc­tures can be con­fig­ured to sur­vive in the harsh elec­tro­chem­i­cal envi­ron­ment of an elec­trolyz­er cell could make it pos­si­ble to reach down to 0.1 mg iridium/​cm².

High irid­i­um usage has long been a major tech­ni­cal chal­lenge for the rapid­ly grow­ing green hydro­gen indus­try pro­duced from inter­mit­tent ener­gy sources such as solar and wind pow­er, as today’s con­ven­tion­al PEM elec­trolyz­ers use around 2.0 mg iridium/​cm². The results from last year’s reli­a­bil­i­ty test with 0.2 mg iridium/​cm² made a big impres­sion in the hydro­gen indus­try, and the com­pa­ny received inquiries from sev­er­al poten­tial cus­tomers who expressed inter­est in con­duct­ing their own tests of the technology.

Our tech­nol­o­gy is expect­ed to sig­nif­i­cant­ly reduce the costs of pro­duc­ing PEM cells. Pre­vi­ous­ly, the will­ing­ness to invest in PEM elec­trolyz­ers has been lim­it­ed by high costs for, among oth­er things, irid­i­um, but now we have proven that we have a solu­tion to this chal­lenge and are well pre­pared for the major growth that is now being scaled up globally.

^{Elli­nor Ehrn­berg, Pres­i­dent of Smoltek Hydrogen}

Read the offi­cial press release of this news.