Spectrophotometric Determination of Oxygen as Its Charge-Transfer Complex with N, N-Dimethylaniline

Rapid Oxidation of the Hole Transport Layer in Perovskite Solar Cells by A Low-Temperature Plasma

“…We then analyzed the oxidized samples by UV-vis spectroscopy. Previous reports 27,28 suggested that if the p -type dopant Spiro-OMeTAD was oxidized by molecular oxygen, and the optical absorption peak of the oxidized Spiro-OMeTAD was located at 400 nm, along with which an additional broad peak at around 500 nm appeared in the spectrum 29 . However, the 400 nm peak was usually indistinguishable because of a strong peak at 395 nm for the non-oxidized Spiro-OMeTAD, and therefore the broad peak at around 500 nm is generally used as the indicator of the oxidized Spiro-OMeTAD 19,30 .…”

“…Thus far, many methods have been studied to shorten the oxidation time of Spiro-OMeTAD, such as exposure in oxygen-containing environment 20 , the addition of other additives 21,22 , using a dicationic salt in Spiro-OMeTAD 23 , and O 3 exposure under a UV light 24 . It was also noticed that the oxidation degree of Spiro-OMeTAD relied on the light intensity 25 , permeated oxygen concentration 26 , and Li + ion concentration 27 . On the other hand, oxygen plasma is known of capability to generate highly reactive radicals, electrons, and ions, and it may improve the oxidation speed of Spiro-OMeTAD in perovskite solar cells.…”

Lithium salts as “redox active” p-type dopants for organic semiconductors and their impact in solid-state dye-sensitized solar cells

“…46 It is well known that in the primary processes of photooxidation, molecular oxygen plays the role of p-dopant. [47][48][49][50][51][52] To probe whether oxygen is involved in the oxidation of Spiro-OMeTAD, we prepared devices for measuring conductivity in oxygen-free conditions with and without the addition of a standard amount (10 mol% with Spiro-OMeTAD) of Li-TFSI. In Fig.…”