Perovskites have long been viewed as a promising alternative to silicon in solar energy. The materials offer the potential for higher efficiency and lower manufacturing costs.

Perovskites are defined by a shared crystalline structure. They display properties such as high superconductivity, magnetoresistance, and ferroelectricity. Thin-film perovskite solar cells can absorb a broader range of wavelengths than silicon.

This allows perovskite cells to reach efficiencies near 40 percent. Silicon solar cells face theoretical efficiency limits near 30 percent. However, perovskites degrade easily when exposed to moisture, heat, and other environmental factors.

Researchers at the University of Cambridge have now developed a more stable halide perovskite. The material was engineered by adjusting its structure at the atomic level.

The team used a vapor-based method to build two- and three-dimensional perovskites layer by layer. This approach allowed precise control of film thickness down to fractions of an atom. Layers were produced at the angstrom scale, or one-tenth of a nanometer.

The layers were stacked so their atomic structures aligned exactly. This alignment allows electrons and positively charged holes to move freely. The process is similar to techniques used in commercial semiconductor manufacturing.

The layered structure directs electric charges efficiently and reduces energy loss as heat. The researchers achieved energy differences between layers greater than half an electron volt. Electron and hole lifetimes exceeded 10 microseconds, far longer than typical values.

Perovskite solar technology has progressed rapidly in recent years. In 2012, thin-film perovskite cells first surpassed 10 percent efficiency. Since then, efficiencies have increased to more than 30 percent in advanced designs.

In 2024, Chinese solar manufacturer Longi reported a power conversion efficiency of 34.6 percent for a perovskite-silicon tandem cell. The result was certified by the European Solar Test Installation. The company said the performance was achieved through improvements in deposition and passivation techniques.

Longi has set multiple efficiency records over the past four years. Its latest results exceeded the Shockley-Queisser theoretical limit for single-junction cells.

Separately, Qcells achieved a record efficiency of 28.6 percent for a large-area silicon cell with a perovskite top layer. The result highlights the potential for smaller projects and reduced land use compared to conventional solar installations.