This Solar Cell Just Set an Astounding Efficiency Record

Caroline Delbert
·3-min read

From Popular Mechanics

  • Scientists have set a new efficiency record for perovskite-silicon solar cells.

  • They've almost reached a critical "proof of concept" milestone of 30 percent, clocking 29.15 percent in this experiment.

  • Perovskite covers parts of the spectrum that silicon alone doesn't grab.

Researchers have reached a new efficiency record for a valuable type of solar panel, inching “tantalizingly” close to a coveted 30 percent milestone.

The solar panels are made of a layered combination of two effective semiconductors that work together, improving on all-silicon panels by adding “up and coming new challenger” perovskite.

The cell in this research is a tandem cell, meaning it’s a single cell that has multiple wavelength phases. Think of this like first sweeping the floor and then using a mop: you’re catching different kinds of stuff by using two approaches.

This new cell layers perovskite and silicon with the right amount of buffer in between to let them both work at peak efficiency.

Cells like the one in this research—which is just one square centimeter in surface area—are made by “self-assembled” materials, meaning organic materials that spread, organize, and form the interface between panel surfaces kind of on their own. That means the field of study of these materials is pretty new, and there’s a lot of room for artful improvements that will drastically increase efficiency.

That’s what these researchers did, using “specially tweaked layer compositions for both connecting the electrode layer and keeping the two types of cell together in order to reach their new record,” ScienceAlert reports.

Careful design lets them use perovskite at its best efficiency without causing phase instability that’s common in existing iterative designs.

☀️ The Best Solar Panels for Your Home

ScienceAlert says scaling up the one centimeter panel should be pretty straightforward, but it’s not clear that’s true. Finding the right balance between optimized perovskite film and the most effective, scalable interface materials—the stuff that grows itself between the layers of solar materials—is still a work in progress.

But that’s why this record is so exciting: it’s good by itself, and it’s cause to be optimistic about the future of perovskite tandem cells.

Photo credit: Eike Köhnen/HZB
Photo credit: Eike Köhnen/HZB

So what is perovskite, and why are we bothering? Perovskite is “synthetic compounds that have an orthorhombic crystal structure identical to the naturally occurring mineral with the same name and that share a structurally similar chemical formula,” ScienceDirect explains.

In nature, perovskite is “found as brilliant black cubes in many mafic igneous rocks, in their associated pegmatites, and in metamorphic contact zones,” Britannica explains—meaning iron-rich and even quartz-mix volcanic rocks. Perovskite is calcium titanate, with the bewitching chemical symbol CaTiO3.

The key thing is perovskite is better at absorbing low-wavelength sunlight than silicon is, making it more useful in a variety of contexts. Using both in one solar panel is a slam dunk of maximizing wavelength coverage.

Scientists work with (occasionally) naturally occurring perovskite, lab-made original versions, and slight variations on the crystalline mineral’s structure. They’re certain that some combination of these factors will lead to better and better panels, continuing solar’s meteoric rise from the last 10 years through, experts say, the next 10 and beyond.

🎥 Now Watch This:

You Might Also Like