Sustainability issue
Category: Energy
Perovskite solar cells have revolutionized the field of thin-film photovoltaics in less than one decade. However, tiny defects in the crystalline structure of perovskites – called traps – can cause electrons to get stuck before their energy has been harnessed. The easier an electron can move around in a solar cell material, the more efficient that material will be at converting photons, or particles of light, into electricity. These so-called traps hamper the efficiency of the perovskite material.
A team of Researchers from the Universities of Cambridge, Oxford and Bath, Massachusetts Institute of Technology and Delft University of Technology reports that these defects can be permanently healed by exposing it to light and just the right amount of humidity.
Technology solution
- The team used techniques compatible with scalable roll-to-roll processes to print a perovskite-based device, but before the device was completed, they exposed it to light, oxygen and humidity.
- Perovskites frequently start to degrade when exposed to humidity, but the team found that when humidity levels were between 40 and 50%, and the exposure was limited to 30 minutes, the perovskite did not degrade.
- Once the exposure was complete, the remaining layers were deposited to finish the device.
- When the light was applied to the material, electrons bound with oxygen, forming a superoxide that could very effectively bind to electron traps and prevent them from hindering electrons.
- In the accompanying presence of water, the perovskite surface also gets converted to a protective shell. The shell coating removes traps from the surfaces but also locks in the superoxide, meaning that the performance improvements in the perovskites are now long-lived.
Stakeholder
- Consumers
- Utility companies
- Organizations that are related to greenhouse gas and climate change
- Energy companies that aim at the utilization of solar energy
- Government department which is responsible for the city residency’s energy supply
Implementation steps
Step 1: Introduce this new technology via a variety of methods to the government, energy companies and citizens.
Step 2: Set up workshop and studio to show audience about the feasibility and potential market of the technology.
Step 3: Establish a corporation relationship with the government and build an incentive system to encourage people to get involved with this technology.
Source
http://www.cell.com/joule/fulltext/S2542-4351(17)30021-1
http://www.sciencemag.org/news/2016/12/low-cost-solar-cells-poised-commercial-breakthrough
https://www.azom.com/article.aspx?ArticleID=14450
Comment on Another Blog Post
Post: IoT powered by wireless signals
Comment: One version of the called passive Wi-Fi, is being commercialized through a spin-off company, Jeeva Wireless. It allows battery-free devices connect with traditional devices such as computers and mobile phones by backscattering Wi-Fi signals. In tests, prototype passive Wi-Fi unit have beamed data as far as 100 feet and made connections through walls. Doing that requires changing the software of a Wi-Fi access point to generate an additional signal for passive Wi-Fi devices to use, very slightly increasing its power consumptions.
UNI – wy2283