In 2022,Cardeynaels, Tom; Etherington, Marc K.; Paredis, Simon; Batsanov, Andrei S.; Deckers, Jasper; Stavrou, Kleitos; Vanderzande, Dirk; Monkman, Andrew P.; Champagne, Benoit; Maes, Wouter published an article in Journal of Materials Chemistry C: Materials for Optical and Electronic Devices. The title of the article was 《Dominant dimer emission provides colour stability for red thermally activated delayed fluorescence emitter》.Safety of tert-Butyl carbamate The author mentioned the following in the article:
Color purity and stability in multi-donor thermally activated delayed fluorescence (TADF) emitters has significant implications for com. organic light-emitting diode (OLED) design. The formation of emissive dimer states in the well-known 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) chromophore at elevated dopant concentrations has recently been confirmed both exptl. and via theor. calculations, indicating that multi-donor emitters such as 4CzIPN might suffer from a lack of color stability due to the presence of multiple emissive states. This poses a serious issue for OLED manufacturers. In this work, dithieno[3,2-b:2′,3′-d]pyrrole (DTP) is applied as an alternative donor unit in a TADF emitter for the first time. In combination with isophthalonitrile (IPN), the 4CzIPN analog termed 4DTPIPN is obtained. The strong electron donating nature of the DTP moiety gives rise to a red shift of the emission with respect to that of 4CzIPN. We identify that 4DTPIPN has a very stable emission spectrum throughout all solid-state thin film concentrations and host materials. Rather interestingly, this color stability is obtained via the formation of dimer/aggregate species that are present even at 0.01 wt% concentration Unfortunately, the higher color stability is paired with a low photoluminescence quantum yield, making 4DTPIPN unviable for device applications. Nonetheless, this work shows the importance of dimer contributions, even at dilute doping concentrations This mol. and study provide important understanding of the aggregation behavior of small-mol. emitters necessary for the successful application of doped and, especially, non-doped OLED architectures. In the experiment, the researchers used tert-Butyl carbamate(cas: 4248-19-5Safety of tert-Butyl carbamate)
tert-Butyl carbamate(cas: 4248-19-5) belongs to anime. Acylation is one of the most important reactions of primary and secondary amines; a hydrogen atom is replaced by an acyl group (a group derived from an acid, such as RCOOH or RSO3H, by removal of ―OH, such as RC(=O)―, RS(O)2―, and so on). Reagents may be acid chlorides (RCOC1, RSO2C1), anhydrides ((RCO)2O), or even esters (RCOOR′); the products are amides of the corresponding acids.Safety of tert-Butyl carbamate
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics