Researchers fabricate carbon electrode perovskite solar cells with 20.8% effectiveness

• Scientists from China's Henan University and also Chinese Academy of Sciences (CAS) have actually reported an extremely efficient carbon electrode perovskite solar cell that apparently attains a power conversion efficiency of 20.8% while offering enhanced stability.

Generally used metal contact electrodes can advertise the deterioration of perovskite solar cells because of the diffusion of metal impurities throughout the user interfaces. This issue could be theoretically overcome by changing the metal contact with carbon electrodes, which are very promising for commercialization due to their ambient stress processability based upon industrially developed printing methods. The trouble is, nevertheless, that perovskite solar cells based on carbon electrodes result in performance losses at the point where the carbon electrode fulfills the perovskite layer.

" For carbon electrode perovskite solar cells, the interfacial contact between carbon electrode as well as perovskite is of excellent importance to the performance of solar cells," the scientists said in their recent study. "The majority of inorganic hole transport layers (HTLs) are based upon dispersive nanoparticles those might easily aggregate to create rough contact with both perovskite as well as the thick carbon paste; the holes collection is hence adversely impacted."

They tried to fix this issue by putting an organic semiconducting polymer called polythiophene (P3HT) in between perovskite and an HTL constructed from nickel(II) oxide (NiOx) and reported that this organic/inorganic planar HTL structure has premium electrical contact for carbon electrode perovskite solar cells.

"The natural P3HT layer allows reliable moisture-inhabitation as well as largely called interface with matched energy-level placement with perovskite, while the stable NiOx nanoparticle layer even more shields P3HT from being rusted by carbon paste to ensure that we can better maximize carbon blade-coating deposition to create densely contact with HTL," the team explained.

The research team developed the cell with a substrate constructed from indium tin oxide (ITO), a tin(IV) oxide (SnO2) barrier layer, a perovskite absorber, the P3HT layer, the HTL constructed from NiOx, and a carbon electrode. The electrode is based upon a carbon paste containing carbon black and graphite powder supplied by Saidi Innovation Development Inc., China. "Carbon electrode was prepared by blade-coating process and the damp movie was hardened at 110 C for 5 minutes," the group clarified.

The scientists contrasted the efficiency of the solar cell keeping that of a recommendation tool without the changed anode barrier user interfaces, which they state are able to promote fee collection.

The champion solar cell constructed with these interfaces achieved a power conversion effectiveness of 20.8%, an open-circuit voltage of 1.15 eV, a short-circuit current of 22.9 mA/cm2, as well as a fill factor of 78.8%.

"This performance is among the top values of carbon electrode perovskite solar cells; a champion performance of 22% was reported from assembly of semi-cells with carbon electrode substrate," they stated. "The functional security of this cell certainly enhances as a result of an introduction of the hydrophobic P3HT layer and also the thick carbon pre-covering". The recommendation tool, by contrast, got to an efficiency of just 13.4%.