And of course, along the way, there was a tremendous amount of support from the whole PVLab team and our collaborators from institutes around the world. Thanks to all of them for making this work possible.
This reflected light back into the middle cell. Combined, these techniques lead to >30% efficient 3Js certified by SIMIT. This one has some years in the making, and I'm proud of Kerem for all of his hard work spearheading this work and pushing it over the finish line.
Third, inspired by previous work on micromorph silicon 3js and back reflectors to maximize current in 2Js, Kerem introduced a "middle reflector." A layer of SiOx nanoparticles was used to intentionally create a refractive index mismatch between the medium bandgap perovskite and Si bottom cell.
First, we deposited a spin-coated medium bandgap perovskite that had been used in multiple records leading up to 2024. Next, we performed a PVD-spin coat hybrid deposition on top, which allowed us to increase thickness and thus middle cell current without sacrificing much optoelectronic quality.
We found that simply making the middle cell thicker using standard spin coating methods lead to deteriorated optoelectronic properties. So, the second strategy was to use a three-step additive deposition method.
Rather than tackling the challenge of making stable and efficient tin-perovskites, we chose the path of maximizing the current we can extract from state of the art FAPbI3 based absorbers.
To push beyond this limit, we noted that one of the main losses in 3Js so far has been poor current matching, which originates from the difficulty of tuning the middle cell bandgap without alloying lead with tin and potentially compromising the cell stability.
It reduces recombination losses without reducing stability. It seems to work quite well for several compositions and bandgap, and allowed us to ~match previous 3J records at the time.
We employed three main strategies. First, Kerem selected hydroxybenzylamine as an additive for the top cell. HBA stays in the film after annealing and is present throughout the thickness, suggesting possible grain boundary wrapping.
New paper alert! Published last week in Nature #perovsky
Paper: www.nature.com/articles/s41...
PDF: rdcu.be/e8C2f
Here, Kerem presents our work to achieve >30% efficient perovskite-perovskite-silicon triple junction (3J) solar cells.
I’m one of the authors on the triple junction paper, and I think to some extent the field is quite close, but in the end we will only know once the modules are tested in the field. We try to simulate degradation in the lab, but in real life things are complex and pathways exist we don’t imagine yet.
A new perovskite-silicon triple-junction solar cell has achieved a certified efficiency of 30.02%, surpassing previous records and advancing scalable, high-performance photovoltaic technology. doi.org/hbswwd
Person holding a record efficiency for perovskite-silicon triple-junction solar cell.
30.02% certified efficiency for a perovskite-based triple-junction solar cell, reported in @natureportfolio.nature.com That sets a new benchmark for this device class. @csem.ch contributed expertise in device engineering, silicon integration, optical management and characterization: bit.ly/4cZCsaR
I want to sincerely thank all of our excellent collaborators on this work, without whom I could not have finished this in the limited time I had left, especially Kerem Artuk who showed me all his tricks to make efficient and reproducible tandems.
I wish we had more time to expand on some interesting observations along the way, but this fact shows the potential of these kinds of processes, and that there is still a lot to learn and achieve here.
The craziest thing is that all this work was completed in the last three months of my postdoc, as I challenged myself to make efficient tandems before leaving the world of CSS perovskites.
Since then, excellent work from Yi Hou and a great preprint from the group of Steve Albrecht (and possibly more since I left academia last month!) have shown coevaporation processes are similarly capable of making highly efficient 2T tandems.
This article is meant to be a showcase of the capabilities of what PVD-CSS is capable of, as at the time of submission all available reports of tandems with vapor deposited perovskite absorbers were <28%.
During the review process we used the same process on textured silicon bottom cells and also demonstrated ~28% efficiency for the same absorbers on textured silicon bottom cells even before additional optimization.
Here, we use a PVD-CSS process to demonstrate >29% stabilized efficiency planar perovskite-silicon tandem solar cells with low hysteresis and good shelf stability.
Can two-step vapor-deposition processes make efficient single junction perovskite and perovskite/silicon tandem solar cells? Last August we found the answer is yes, published today in ACS Energy Letters!
pubs.acs.org/doi/10.1021/...
Here, we use a PVD-CSS process to demonstrate >29% stabilized efficiency planar perovskite-silicon tandem solar cells with low hysteresis and good shelf stability. During review we used the same process on textured silicon and demonstrated ~28% efficiency for the same absorbers without optimization.
Narges Yaghoobi Nia et al. form 2D perovskite co-crystals with neutral templating molecules, improving the stability of perovskite solar modules.
In this Review, Julian A. Steele links the atomistic origins of anharmonic lattice vibrations in metal halide perovskites to the macroscopic thermo-mechanical properties of the materials and solar cells.
FBI agents executed a search warrant on Wednesday for an election center in Fulton County, Georgia, seeking to seize ballots in a significant escalation of the Trump administration’s efforts to investigate a jurisdiction that Trump has continued to criticize over his 2020 defeat in the state.
Yesterday, Jack Smith was able to tell the American people what he found from his extensive investigation: that Donald Trump committed criminal acts by trying to overturn the 2020 election.
Leading up to and on January 6th, Trump attempted to end our democracy.
A second American citizen has been killed by immigration agents in Minneapolis, and DHS is blocking any independent investigation. When will my Republican colleagues speak out against this chaos? This can’t continue.
Masked government agents are conducting “show me your papers” stops, detaining 5-year-olds to use them as bait, and brutally murdering U.S. citizens.
Call it what it is — fascism.
History will not look fondly on politicians and so-called "leaders" of this country who stood by and enabled this.
Trump admin once again lying with speed and abandon with no regard to the facts
