Sungkyunkwan University (SKKU) researchers have simulated a tandem solar cell with two absorbers based on methylammonium lead triiodide (CH3NH3PbI3) – a perovskite with high photoluminescence quantum yield – and molybdenum ditelluride (MoTe2), which is known for being naturally p-doped, with cascaded bandgaps to absorb a wider solar spectrum.
“The proposed cell configuration can overcome the present limitations of solar light absorption in perovskite solar cells,” researcher Mohammad Gholipoor told pv magazine. “We think this cell can be another new solution to mitigate this problem.”
The scientists built the cell with an indium tin oxide (ITI) substrate, an electron transport layer (ETL) based on titanium oxide (TiO2), a CH3NH3PbI3 layer, a MoTe2 layer, a spiro-OMeTAD hole-blocking layer, and a silver (Ag) metal contact.
“The excellently desirable band alignment of MoTe2 with other layers, along with its high near-infrared (NIR) absorption capacity, remarkably paves the way for achieving higher photovoltaic efficiency,” they explained, noting that the ideal thickness of the MoTe2 absorber should be around 25 nanometers.
They found that the CH3NH3PbI3 and MoTe2 layers contributed to 61% and 39% of carrier generation, respectively. They noted that a cell fabricated with this configuration could reach a power conversion efficiency of 20.32%.
“The calculated results show an appreciable increase in the perovskite solar cell efficiency originating from the short circuit current, compared to the cell without MoTe2,” they said.
However, stacking the absorbers with different bandgaps led to a decline in the open-circuit voltage, due to the hole transport deterioration in the absorbing area.
“In order to alleviate the unavoidable issue, we inserted a graphene oxide layer with a thickness of 1.5 nm. Consequently, we observed that the open circuit voltage increases as much as 0.1 eV,” they said.
They presented the new cell design in “High-performance parallel tandem MoTe2/perovskite solar cell based on reduced graphene oxide as hole transport layer,” which was recently published in Scientific Reports. They are now trying to get experimental results in line with their simulation results.
This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: editors@pv-magazine.com.
1 comment
By submitting this form you agree to pv magazine using your data for the purposes of publishing your comment.
Your personal data will only be disclosed or otherwise transmitted to third parties for the purposes of spam filtering or if this is necessary for technical maintenance of the website. Any other transfer to third parties will not take place unless this is justified on the basis of applicable data protection regulations or if pv magazine is legally obliged to do so.
You may revoke this consent at any time with effect for the future, in which case your personal data will be deleted immediately. Otherwise, your data will be deleted if pv magazine has processed your request or the purpose of data storage is fulfilled.
Further information on data privacy can be found in our Data Protection Policy.