A research group at the Japan-based National Institute for Materials Science (NIMS) reported the achievement of energy conversion efficiency exceeding 18% using standard size (1 cm2) perovskite solar cells. This measurement was made by the Calibration, Standards and Measurement Team at the Research Center for Photovoltaics, National Institute of Advanced Industrial Science and Technology (AIST)—an internationally recognized independent organization for solar cell evaluation.

The research group developed high-quality crystal particles that constitute a perovskite layer by adjusting the ratio of different cations in the layer and by substituting some of the iodine with bromine. Consequently, they were able to efficiently extract electrons and holes formed by exposure to light, and succeeded in increasing the short-circuit current density to more than 21 mA/cm2. Furthermore, they accurately controlled the thickness of layers in solar cells such as perovskite and electron transport layers and thereby reduced electrical resistance within the solar cells. As a result, they were able to reach this increased conversion efficiency of 18.2%.

Researchers at Purdue University have found that nickel-based perovskites have exceptional properties for use as solid electrolytes in fuel cells. Unlike conventional electrolytes, these nickel-based perovskites are chemically stable in the fuel cell’s environment, which could lead to higher performing and longer lasting fuel cells.

Schematic of the perovskite samarium nickelate (SNO)-electrolyte solid-oxide fuel cell.

Solid-oxide fuel cells are considered as one of the most efficient types of fuel cells. They typically use polymers or ceramics as an electrolyte, but finding an effective solid electrolyte—one that conducts protons but blocks electrons—at low operating temperatures of 300–500°C has been a challenge. Most materials, when exposed to low pressure, start to lose oxygen and become electron conductors; The electrolyte separator becomes leaky so it can short circuit the fuel cell or it can start to crack and allow fuel to mix with oxygen.