AFRL researchers explore automation, additive technologies for cost … – Phys.Org

July 19, 2017 Dr. Santanu Bag, a project scientist at the Materials and Manufacturing Directorate, Air Force Research Laboratory, is exploring cost-efficient manufacturing of solar cells using additive technology. Credit: Air Force Office of Scientific Research

Inspired by newspaper printing, and taking cues from additive manufacturing technology, researchers at the Air Force Research Laboratory are exploring new ways to make solar cells more cost efficientincreasing application potential in the process.

"Sun is abundant, and it's free," said Dr. Santanu Bag, a project scientist at the Materials and Manufacturing Directorate, AFRL. "Solar cells can generate electricity in an environmentally friendly way, but current, complex fabrication costs make the technology expensive. We're looking at new ways to use materials and manufacturing technologies to make these less expensively."

Though research into solar cells began in the 1950s, the technology for making them is complex and labor intensive. At a basic level, to fabricate solar cells, engineers rely on extremely pure, single-crystalline silicon. The pure silicon is extracted from an original material such as quartz or sand and is transformed into thin wafers. The silicon wafers are chemically treated to form an electric field, with a positive and negative polarity. These silicon semiconductors, or solar cells, are encapsulated in a support to form a photovoltaic module, where they are then able to collect and transform sunlight into an electric current.

This multistep, labor intensive process is time-consuming and uses highly sophisticated equipment, requiring a number of technicians and engineers to create the end product. Quality control is key, as a discrepancy during any stage of the manufacturing process could have an effect on the performance of the cells.

This high cost of manufacturing has prohibited widespread use of solar power, despite its cost saving potential.

"If you want to make solar competitive, you need to make solar cells more efficient and cost effective," said Bag.

Inspired by the concept of newsprint where rolls of paper are printed with ink to create newspapers, Bag and his team looked for alternatives to inorganic, hard silicon in search of a material able to transform solar into energyand be printed in the process.

"Silicon cells use purely inorganic materials, which by nature are very hard," said Bag. "We needed a material that was easy to print and at the same time able to capture sunlight. We determined an inorganic-organic hybrid material would be easy to print and could still harvest solar energy."

Bag's material of choice, thin-film perovskites, have an excellent light absorbing capability and power conversion efficiencies that have improved tremendously compared to the more than 30 years it took for silicon solar cells to improve to today's levels. Only recently has this material been explored for its solar power ability, with Bag among the researchers expanding the field.

"The material has been around since the 1990s and was used to make test-level, light-emitting diodes. Researchers knew it had solar ability, but this was not the focus at the time," said Bag.

In Bag's study, perovskite precursor material was atomized using ultrasonic waves to form extremely fine, aerosol droplets able to be transferred into the print nozzle of an aerosol-jet spray printer. Using computer-aided design tool paths, a surface was then coated with the material using the direct-write printer, forming a solar cell with a 15.4 percent efficiency on a flat surface.

Bag and his team also demonstrated the ability to print these solar cells on a 3-D surface with a 5.4 percent efficiencymarking the first time this has been shown in the field of printed photovoltaics.

"We have not optimized conditions for 3-D printing of these yet, but we know it can be done. Once you know how to print it, it has huge potential for other applications," said Bag.

For the Air Force, the applications for this material and the new printing process are enormous. The method can be used to print flexible solar cells on clothing, to create self-powered robotics and light-emitting devices and even to make flexible, self-powered sensors, to name a few.

Bag, along with fellow researchers Dr. Michael Durstock, Soft Matter Materials Branch Chief at the AFRL Materials and Manufacturing Directorate, and James Deneault, a research engineer at Universal Technology Corporation, have filed a patent application for the technology. Though this research is still in its early stages, the impact of the new manufacturing processes has great potential for the future.

"Understanding ways to make and print this material more efficiently at the most basic level can lead to future cost savings," Bag concluded.

Explore further: Semi-transparent perovskite solar cells for solar windows

More information: Santanu Bag et al. Aerosol-Jet-Assisted Thin-Film Growth of CH3 NH3 PbI3 Perovskites-A Means to Achieve High Quality, Defect-Free Films for Efficient Solar Cells, Advanced Energy Materials (2017). DOI: 10.1002/aenm.201701151

Journal reference: Advanced Energy Materials

Provided by: Air Force Office of Scientific Research

Scientists are exploring ways to develop transparent or semi-transparent solar cells as a substitute for glass walls in modern buildings with the aim of harnessing solar energy. But this has proven challenging, because transparency ...

Researchers at The Australian National University (ANU) have achieved a new record efficiency for low-cost semi-transparent perovskite solar cells in a breakthrough that could bring down the cost of generating solar electricity.

An organic-inorganic hybrid material may be the future for more efficient technologies that can generate electricity from either light or heat or devices that emit light from electricity.

A recent study, affiliated with UNIST has presented a new cost-efficient way to produce inorganic-organic hybrid perovskite solar cells (PSCs) which sets a new world-record efficiency performance, in particular photostability. ...

Five years ago, the world started to talk about third-generation solar cells that challenged the traditional silicon cells with a cheaper and simpler manufacturing process that used less energy.

Researchers at ANU have found a new way to fabricate high efficiency semi-transparent perovskite solar cells in a breakthrough that could lead to more efficient and cheaper solar electricity.

An underwater robot entered a badly damaged reactor at Japan's crippled Fukushima nuclear plant Wednesday, capturing images of the harsh impact of its meltdown, including key structures that were torn and knocked out of place.

Microsoft's cloud computing platform will be used outside China for collaboration by members of a self-driving car alliance formed by Chinese internet search giant Baidu, the companies announced on Tuesday.

Laboratory equipment is one of the largest cost factors in neuroscience. However, many experiments can be performed with good results using self-assembled setups involving 3-D printed components and self-programmed electronics. ...

Access to clean, safe water is one of the world's pressing needs, yet today's water distribution systems lose an average of 20 percent of their supply because of leaks. These leaks not only make shortages worse but also can ...

A virtual reality "space ride" in which viewers feel as if they are flying through the air inside a giant glass ball has been developed in Japan.

Supercapacitors are an aptly named type of device that can store and deliver energy faster than conventional batteries. They are in high demand for applications including electric cars, wireless telecommunications and high-powered ...

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

See original here:

AFRL researchers explore automation, additive technologies for cost ... - Phys.Org