Researchers achieve record efficiency of 25.8% for single junction perovskite solar cell

Researchers at South Korea’s Ulsan National Institute of Science and Technology (UNIST) and Pohang University of Science and Technology report a power conversion efficiency of 25.8% for a single junction perovskite solar cell, by forming a coherent interlayer between electron-transporting and perovskite layers to reduce interfacial defects.

The cell was built with an interlayer between a tin(IV) oxide (SnO2) electron-transporting layer and a layer made of a halide perovskite layer by coupling chlorine-bonded SnO2 with a perovskite precursor containing chlorine. “This interlayer has atomically coherent features which enhance charge extraction and transport from the perovskite layer; and fewer interfacial defects,” the academics explained.

The DoE awards $1.25 million to perovskite research projects, issues an RFI for perovskite efficiency targets

The US Department of Energy (DoE) awarded nearly $40 Million for grid-decarbonizing solar technologies projects. The DoE awarded the funds to 40 research projects, several of which are perovskite related. We'll list the perovskite projects (which were awarded a total of $1.25 million) below.

The DoE also issued a request for information (RFI) to gather input on efficiency, stability and replicability performance targets for perovskite photovoltaic devices that could be utilized to demonstrate technical and commercial readiness for future funding programs.

Researchers show all-inorganic halide perovskites to be highly promising for efficient solar cells

Researchers at UC Santa Barbara recently conducted a research that disproved the common belief that organic molecules are crucial to achieving PSCs' impressive performance because they suppress defect-assisted carrier recombination. Not only was this assumption shown to be incorrect, but the team also found that all-inorganic materials have the potential for outperforming hybrid perovskites.

All-inorganic halide perovskites as candidates for efficient solar cells image

“To compare the materials, we performed comprehensive simulations of the recombination mechanisms,” explained Xie Zhang, lead researcher on the study. “When light shines on a solar-cell material, the photo-generated carriers generate a current; recombination at defects destroys some of those carriers and hence lowers the efficiency. Defects thus act as efficiency killers.”

Researchers report positive results from tests with low-cost fluorene-xantene-based HTM

Researchers at the University of Rome Tor Vergata's Centre for Hybrid and Organic Solar Energy (CHOSE) and ISM-CNR have tested a commercially available HTM with a new core made by low-cost fluorene–xantene units. The experimentation was conducted on small (0.09 cm2) and large area (1.01 cm2) cells.

The one-pot synthesis of this compound is said to drastically reduce its cost compared with the commonly used Spiro-OMeTAD. The optoelectronic performances and properties were characterized through JV measurement, IPCE (incident photon to current efficiency), steady-state photoluminescence and ISOS stability test. SEM (scanning electron microscope) images reveal a uniform and pinhole free coverage of the X55 HTM surface, which reduces the charge recombination losses and improves the device performance relatively to Spiro-OMeTAD from 16% to 17%. The ISOS-D-1 stability test on large area cells without any encapsulation reports an efficiency drop of about 15% after 1000 h compared to 30% for the reference case.