Organic light-emitting diodes (OLEDs) as a display technology can now be found in many different sized consumer electronics from smartwatches to mobile phones to tablet and laptop displays, and large-area televisions. OLEDs offer several advantages compared to inorganic light-emitting diodes (LEDs), such as the ability to be fabricated on flexible substrates, their low operational voltage, high contrast ratio, and relatively lower fabrication cost. OLEDs possess a multilayered structure where the emissive layer is sandwiched between electrodes, charge injection and transporting layers. One of the remaining challenges in OLED design is to address the relatively poorer performance of the blue sub pixel compared to the green and red sub pixels. This is because the red and green sub pixels employ phosphorescent complexes while the blue sub pixel relies on a fluorescent organic compound and so exciton harvesting efficiency is inherently lower. There is at present no viable blue phosphorescent complex emitter whose use translates into an OLED with sufficiently high stability. Blue light has the highest energy of the three primary display colors, meaning that the emitter must possess the largest bandgap, typically exceeding 2.7 eV. This brings up a challenge as efficient emitters that operate via a thermally activated delayed fluorescence (TADF) mechanism typically rely on an electron donor-acceptor (D-A) molecular structure, which results in a charge transfer (CT) excited state that manifests in broad emission and so does not meet the industry requirement for the blue sub pixel CIE chromaticity coordinates of 0.131, 0.046. Typically, large band gap emitters can be obtained by using a combination of weak electron donors and acceptors; however, the choice of weak acceptors is limited. Electron-accepting strength can be quantified by the electron affinity of the compound, which is linked to the energy of the lowest unoccupied molecular orbital (LUMO). One of the most widely explored electron acceptors, 2,4,6-triphenyl-1,3,5-triazine, has LUMO of -1.80 eV (DFT PBE0/6-31G(d,p)) and is considered a relatively strong electron acceptor. Indeed, there are no deep blue TADF emitters that employ this acceptor within the molecular design. Weaker electron acceptors include 1,3,4-oxadiazole (OXD) (LUMO -0.55 eV), pyrimidine (LUMO -1.16 eV), 1,3,4-thiadiazole (LUMO -1.27 eV). Use of stronger donors like 9,9-dimethylacridine (DMAC, HOMO -5.13 eV), phenoxazine (PXZ, HOMO -5.02 eV), or phenothiazine (PTZ, HOMO -5.26 eV) in conjunction with the aforementioned weak acceptors leads to too stabilized singlet excited states for blue emission. Often, green emission is observed even when the weak donor carbazole is used in conjunction with these weak acceptors. The resulting emissive CT state is sensitive to the polarity of the surrounding, hence a red-shifted emission is observed. Deep blue emission is observed only in a handful of reports where a weak acceptor like diphenylsulfone (DPS) (LUMO -1.37 eV) is used with carbazole, or DMAC. Other examples of blue emitters involve boron-containing acceptors, such as DOBNA (LUMO -1.50 eV), or other weak acceptors like trifluoromethylated pyridine (LUMO -1.61 eV). D-A compounds that are based on these acceptors in conjunction with carbazole and even DMAC show blue TADF; however, it is not possible to obtain blue emission when using stronger donors like PXZ. Here we demonstrate blue emission in donor-acceptor systems bearing strong donors by using an ultra-weak electron-accepting imidazole acceptor. Imidazole derivatives have been widely explored as both electron-transporting and emitter materials for OLEDs. The two nitrogen atoms within the imidazole ring, N1 and N3, possess distinct chemistry and confer bipolar character to the imidiazole with N1 being nucleophilic, while N3 is part of a p-accepting imine (Figure ). This N3 nitrogen deepens the LUMO energy of 1,2,4,5-tetraphenylimidazole (TPI) to -0.76 eV, which is comparable to that of OXD (-0.55 eV, PBE0/6-31G(d,p)). As well, the LUMO of TPI is shallower than those of widely used acceptors in blue TADF emitter design, such as triazine (-1.80 eV), isophthalonitrile (-2.13 eV), or diphenylsulfone (DPS) (-1.37 eV), placing TPI as a very weak electron acceptor and a suitable candidate to construct blue emitters.