Silylene-Copper-Amide Emitters: From Thermally Activated Delayed Fluorescence to Dual Emission.

Herein, we report the inaugural instance of NHSi-coordinated copper amide emitters (2-5). These complexes exhibit thermally activated delayed fluorescence (TADF) and singlet-triplet dual emission in anaerobic conditions. The NHSi-Cu-diphenylamide (2) complex demonstrates TADF with a very small ΔEST gap (0.01 eV), an absolute quantum yield of 11%, a radiative rate of 2.55×105 s-1, and a short τTADF of 0.45 µs in the solid state. The dual emissive complexes (3-5) achieve an absolute quantum yield of up to 20% in the solid state with a kISC rate of 1.82×108 s-1 and exhibit room temperature phosphorescence (RTP) with lifetimes up to 9 ms. The gradual decrease in the intensity of the triplet state of complex 3 under controlled oxygen exposure demonstrates its potential for future oxygen-sensing applications. Complexes 2 and 3 have been further utilized to fabricate converted LEDs, paving the way for future OLED production using newly synthesized NHSi-Cu-amides.

Advances in Host-Free White Organic Light-Emitting Diodes Utilizing Thermally Activated Delayed Fluorescence: A Comprehensive Review.

The ever-growing prominence and widespread acceptance of organic light-emitting diodes (OLEDs), particularly those employing thermally activated delayed fluorescence (TADF), have firmly established them as formidable contenders in the field of lighting technology. TADF enables achieving a 100% utilization rate and efficient luminescence through reverse intersystem crossing (RISC). However, the effectiveness of TADF-OLEDs is influenced by their high current density and limited device lifetime, which result in a significant reduction in efficiency. This comprehensive review introduces the TADF mechanism and provides a detailed overview of recent advancements in the development of host-free white OLEDs (WOLEDs) utilizing TADF. This review specifically scrutinizes advancements from three distinct perspectives: TADF fluorescence, TADF phosphorescence and all-TADF materials in host-free WOLEDs. By presenting the latest research findings, this review contributes to the understanding of the current state of host-free WOLEDs, employing TADF and underscoring promising avenues for future investigations. It aims to serve as a valuable resource for newcomers seeking an entry point into the field as well as for established members of the WOLEDs community, offering them insightful perspectives on imminent advancements.

Structure Engineering of Acridine Donor to Optimize Color Purity of Blue Thermally Activated Delayed Fluorescence Emitters.

9,9-Dimethyl-9,10-dihydroacridine (DMAC) is one of the most widely used electron donor for constructing high-performance thermally activated delayed fluorescence (TADF) emitters. However, DMAC-based emitters often suffer from the imperfect color purity, particularly in blue emitters, due to its strong electron-donating capability. To modulate donor strength, 2,7-F-Ph-DMAC and 2,7-CF3-Ph-DMAC were designed by introducing the electron-withdrawing 2-fluorophenyl and 2-(trifluoromethyl)phenyl at the 2,7-positions of DMAC. These donors were used, in combination with 2,4,6-triphenyl-1,3,5-triazine (TRZ) acceptor, to develop novel TADF emitters 2,7-F-Ph-DMAC-TRZ and 2,7-CF3-Ph-DMAC-TRZ. Compared to the F- or CF3-free reference emitter, both two emitters showed hypsochromic effect in fluorescence and comparable photoluminescence quantum yields without sacrificing the reverse intersystem crossing rate constants. In particular, 2,7-CF3-Ph-DMAC-TRZ based OLED exhibited a blue shift by up to 39 nm and significantly improved Commission International de l'Éclairage (CIE) coordinates from (0.36, 0.55) to (0.22, 0.41), while the external quantum efficiency kept stable at about 22.5 %. This donor engineering strategy should be valid for improving the color purity of large amount of acridine based TADF emitters. It can be predicted that pure blue TADF emitters should be feasible if these F- or CF3-modifed acridine donors are combined with other weaker electron acceptors.

B‒N covalent bond-involved π-extension of multiple resonance emitters enables high-performance narrowband electroluminescence.

Multi-boron-embedded multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters show promise for achieving both high color-purity emission and high exciton utilization efficiency. However, their development is often impeded by a limited synthetic scope and excessive molecular weights, which challenge material acquisition and organic light-emitting diode (OLED) fabrication by vacuum deposition. Herein, we put forward a B‒N covalent bond-involved π-extension strategy via post-functionalization of MR frameworks, leading to the generation of high-order B/N-based motifs. The structurally and electronically extended π-system not only enhances molecular rigidity to narrow emission linewidth but also promotes reverse intersystem crossing to mitigate efficiency roll-off. As illustrated examples, ultra-narrowband sky-blue emitters (full-width at half-maximum as small as 8 nm in n-hexane) have been developed with multi-dimensional improvement in photophysical properties compared to their precursor emitters, which enables narrowband OLEDs with external quantum efficiencies (EQEmax) of up to 42.6%, in company with alleviated efficiency decline at high brightness, representing the best efficiency reported for single-host OLEDs. The success of these emitters highlights the effectiveness of our molecular design strategy for advanced MR-TADF emitters and confirms their extensive potential in high-performance optoelectronic devices.

Polymorphism Dependent Cytotoxicity, Cellular Uptake, and Live Cell Imaging Studies on Napthalimide-Vinyl-Phenothiazine Conjugate.

Polymorphism-dependent cytotoxicity and cellular uptake of drug molecules have been studied for the past two decades. However, the visualization of polymorph-dependent cellular uptake and cytotoxicity using microscopy imaging techniques has not yet been reported. The luminescent polymorph is an ideal candidate to validate the above hypothesis. Herein, we report the polymorph-dependent cellular uptake, cytotoxicity, and bio-imaging functions of polymorphs 1Y and 1R of a naphthalimide-phenothiazine dyad. These polymorphs show different luminescence colors in the solid state and exhibit aggregation-induced enhanced emission (AIEE) in the DMSO-Water mixture. Bioimaging, cytotoxicity assay, and fluorescence-activated cell sorting (FACS) studies revealed that these polymorphs show different levels of cytotoxicity, cellular uptake, localization, and imaging potential. Detailed photophysical, morphological, and biological studies revealed that the difference in molecular conformation in these polymorphs enables them to form aggregates of different sizes and morphology, which leads to the differential uptake of these into the cells and consequently shows different cytotoxicity and imaging potentials.

Tailored Fabrication of Full-Color Ultrastable Room-Temperature Phosphorescence Carbon Dots Composites with Unexpected Thermally Activated Delayed Fluorescence.

The development of single-system materials that exhibit both multicolor room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) with tunable after glow colors and channels is challenging. In this study, four metal-free carbon dots (CDs) are developed through structural tailoring, and panchromatic high-brightness RTP is achieved via strong chemical encapsulation in urea. The maximum lifetime and quantum yield reaches 2141 ms and 56.55%, respectively. Moreover, CDs-IV@urea, prepared via coreshell interaction engineering, exhibits a dual afterglow of red RTP and green TADF. The degree of conjugation and functional groups of precursors affects the binding interactions of the nitrogen cladding on CDs, which in turn stabilizes triplet energy levels and affects the energy gap between S1 and T1 (ΔEST) to induce multicolor RTP. The enhanced wrapping interaction lowers the ΔEST, promoting reverse intersystem crossing, which leads to phosphorescence and TADF. This strong coreshell interaction fully stabilizes the triplet state, thus stabilizing the material in water, even in extreme environments such as strong acids and oxidants. These afterglow materials are tested in multicolor, time, and temperature multiencryption as well as in multicolor in vivo bioimaging. Hence, these materials have promising practical applications in information security as well as biomedical diagnosis and treatment.

Multifunctional Deep-Blue Thermally Activated Delayed Fluorescence Based on an Oxygen-Bridged Boron Acceptor for Highly Efficient Organic Light-Emitting Diodes.

Until now, thermally activated delayed fluorescence (TADF) materials based on bridged boron-based acceptors have been primarily developed as dopants. However, in this study, we synthesized and characterized multifunctional deep-blue TADF materials─t-OBO-DMAC and t-OBO-DPAC─using bridged boron-based acceptors in combination with dimethylacridine or diphenylacridine as donors. These materials serve as both dopants and hosts. Theoretical calculations and experimentally measured photophysical properties of t-OBO-DMAC reveal a smaller singlet-triplet energy difference, higher photoluminescence quantum yield, and more efficient reverse intersystem crossing compared to t-OBO-DPAC. When evaluated as TADF emitters, t-OBO-DMAC and t-OBO-DPAC exhibited maximum external quantum efficiency (EQE) of 14.4 and 7.3% with deep-blue color coordinates of (0.14, 0.11) and (0.15, 0.07), respectively. Both materials were further assessed as hosts in various configurations, including host-only, TADF, phosphorescent, and phosphor-sensitized fluorescence (PSF)-emitting systems. Notably, t-OBO-DMAC demonstrated a high maximum EQE of 13.9% with deep-blue color coordinates of (0.15, 0.07) in a nondoped host-only device. Remarkably, both materials achieved EQEs exceeding 20% in the PSF devices. Our study marks a critical advancement in the field that breaks the conventional boundaries of the dopant and host and demonstrates unprecedented multifunctionalities for advanced organic light-emitting diodes.

Efficient Blue Photo- and Electroluminescence from CF3-Decorated Cu(I) Complexes.

Luminescent organometallic complexes of earth-abundant copper(I) have long been studied in organic light-emitting diodes (OLED). Particularly, Cu(I)-based carbene-metal-amide (CMA) complexes have recently emerged as promising organometallic emitters. However, blue-emitting Cu(I) CMA complexes have been rarely reported. Here we constructed two blue-emitting Cu(I) CMA emitters, MAC*-Cu-CF3Cz and MAC*-Cu-2CF3Cz, by introducing one or two CF3 substitutes into carbazole ligands. Both complexes exhibited high thermal stability and blue emission colors. Moreover, two complexes exhibited different emission origins rooting from different donor ligands: a distinct thermally activated delayed fluorescence (TADF) from ligand-to-ligand charge transfer excited states for MAC*-Cu-CF3Cz or a dominant phosphorescence nature from local triplet excited state of the carbazole ligand for MAC*-Cu-2CF3Cz. Inspiringly, MAC*-Cu-CF3Cz had high photoluminescence quantum yields of up to 94 % and short emission lifetimes of down to 1.2 µs in doped films, accompanied by relatively high radiative rates in the 105 s-1 order. The resultant vacuum-deposited OLEDs based on MAC*-Cu-CF3Cz delivered pure-blue electroluminescence at 462 nm together with a high external quantum efficiency of 13.0 %.

Through-Space Charge-Transfer Organogold(III) Complexes Enable High-Performance X-ray Scintillation and Imaging.

Organic scintillators have recently attracted growing attention for X-ray detection in industrial and medical applications. However, these materials still face critical obstacles of low attenuation efficiency and/or inefficient triplet exciton utilization. Here we developed a new category of organogold(III) complexes, Tp-Au-1 and Tp-Au-2, through adopting a through-space interaction motif to realize high X-ray attenuation efficiency and efficient harvesting of triplet excitons for emission. Thanks to the efficient through-space charge transfer process, this panel of complexes achieved higher photoluminescence quantum yield and shorter radiative lifetimes compared with the through-bond reference complexes. Inspiringly, these organogold(III) complexes exhibited polarity-dependent emission origins: thermally activated delayed fluorescence and/or phosphorescence. Under X-ray irradiation, Tp-Au-2 manifested intense radioluminescence together with a record-high scintillation light yield of 77,600 photons MeV-1 for organic scintillators. The resulting scintillator screens demonstrated high-quality X-ray imaging with >16.0 line pairs mm-1 spatial resolution, outstripping most organic and inorganic scintillators. This finding provides a feasible strategy for the design of superior organic X-ray scintillators.

High-Efficiency and Narrowband Green Thermally Activated Delayed Fluorescence Organic Light-Emitting Diodes Based on Two Diverse Boron Multi-Resonant Skeletons.

Up to now, highly efficient narrowband thermally activated delayed fluorescence (TADF) molecules constructed by oxygen-bridged boron with an enhancing multiple resonance (MR) effect have been in urgent demand for solid-state lighting and full-color displays. In this work, a novel MR-TADF molecule, BNBO, constructed by the oxygen-bridged boron unit and boron-nitrogen core skeleton as an electron-donating moiety, is successfully designed and synthesized via a facile one-step synthesis. Based on BNBO as an efficient green emitter, the organic light-emitting diode (OLED) shows a sharp emission peak of 508 nm with a full-width at half-maximum (FWHM) of 36 nm and realizes quite high peak efficiency values, including an external quantum efficiency (EQEmax) of 24.3% and a power efficiency (PEmax) of 62.3 lm/W. BNBO possesses the intramolecular charge transfer (ICT) property of donor-acceptor (D-A) materials and multiple resonance characteristics, which provide a simple strategy for narrowband oxygen-boron materials.

Tuning the Electronic and Optical Properties of Phenoxaborin Based Thermally Activated Delayed Fluorescent Materials: A DFT Study.

The electronic and optoelectronic properties of molecules constituted by benzene as linker, phenoxaborin as acceptor coupled with different types of donor moieties are investigated using the density functional theoretical method. The energy gap between the first excited singlet and triplet states (ΔEST) of the designed molecules (1-9) is found to be less than 0.5 eV suggesting them as ideal candidates for thermally activated delayed fluorescence (TADF) emitters. The analysis of frontier molecular orbitals of the molecules revealed a minimum spatial overlap between highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) in favor of the small values of ΔEST. Among the molecules studied, the one in which dihydrophenazine acts as the donor has the lowest value of ΔEST. All designed molecules are good electron transporters. The non-linear optical properties of the molecules are also examined.

Cyano Decoration of π-Bridge to Boost Photoluminescence and Electroluminescence Quantum Yields of Triazine/Carbazole Based Blue TADF Emitter.

In general, a large donor-acceptor dihedral angle is required to guarantee sufficient frontier molecular orbitals separation for thermally activated delayed fluorescence (TADF) emitters, which is intrinsically unfavorable for the radiative transition. We present a molecular design method favoring both reverse intersystem crossing (RISC) and radiative transitions even at a moderate D-A angle. A blue TADF emitter TrzBuCz-CN was designed with triazine/tert-butylcarbazole as donor/acceptor and cyano (CN) incorporated on the phenylene bridge. In comparison with the methyl decoration in similar way (TrzBuCz-Me), CN decoration reduced the D-A dihedral angle from 70° to 60°, which is intrinsically not favorable for sufficient FMO separation, but unexpectedly reduced the singlet and triplet energy gap (ΔEST ) and thus facilitated TADF feature by pulling down the lowest singlet state energy. While the reduced distorsion instead improved the HOMO-LUMO overlap and boosted the fluorescence quantum yield from 41 % to 94 %. The blue organic light-emitting diode of TrzBuCz-CN exhibited an external quantum efficiency of 13.7 % with emission peak at 466 nm, greatly superior to 6.0 % of TrzBuCz-Me. The result provides a feasible design strategy to facilitate both RISC and radiation processes by CN decoration of the linking bridge of TADF emitters.

Exploration of violet-to-blue thermally activated delayed fluorescence emitters based on "CH/N" and "H/CN" substitutions at diphenylsulphone acceptor. A DFT study.

The violet-to-blue thermally activated delayed fluorescence (TADF) emitters were created employing several substituents based on 5,5-dimethyl-5,10-dihydropyrido [2,3-b][1,8] naphthyridine-diphenylsulphone (DMDHPN-DPS) called 1a via "CH/N" and "H/CN" substitutions at the diphenylsulphone acceptor (DPS) moiety. The parent compound 1a was selected from our former work after extensive research employing "CH/N" substitution on Dimethyl-acridine (DMAC) donor moiety. There is a little overlap amid the highest occupied molecular orbitals (HOMOs) and lowest un-occupied molecular orbitals (LUMOs) due to the distribution of HOMOs and LUMOs primarily on the DMDHPN donor and the DPS acceptor moieties, respectively. It resulted in a narrower energy gap (∆E ST) between the lowest singlet (S1) and triplet (T1) excited state. In nearly all derivatives, the steric hindrance results in a larger torsional angle (85°-98°) between the plane of the DMDHPN and the DPS moieties. The predicted ΔE ST values of the compounds with "H/CN" substitution were lower than those of the comparable "CH/N" substituents, demonstrating the superiority of the reversible inter-system crossing (RISC) from the T1 → S1 state. All derivatives have emission wavelengths (λ em) in the range of 357-449 nm. The LUMO → HOMO transition energies in the S1 states are lowered by the presence of -CN groups or -N = atoms at the ortho or meta sites of a DPS acceptor unit, causing the λ em values to red-shift. Furthermore, the λ em showed a greater red-shift as there were more-CN groups or -N = atoms. Three of the derivatives named 1b, 1g, and 1h, emit violet (394 nm, 399 nm, and 398 nm, respectively), while two others, 1f and 1i, emit blue shade (449 nm each) with reasonable emission intensity peak demonstrating that these derivatives are effective violet-to-blue TADF nominees. The lower ΔE ST value for derivative 1i (0.01 eV) with λ em values of 449 nm make this molecule the finest choice for blue TADF emitter amongst all the studied derivatives. We believe our research might lead to the development of more proficient blue TADF-OLEDs in the future.

Highly Efficient OLEDs by Using a Brominated Thermally Activated Delayed Fluorescent Host due to Balanced Carrier Transport and Enhanced Exciton Upconversion.

Thermally activated delayed fluorescent (TADF) materials are naturally bipolar and can potentially serve as hosts. However, triplet excitons in TADF materials are long-lived and prone to unfavorable bimolecular processes. Implementing an efficient reverse system intersection (RISC) process is an effective solution. Moreover, although the general TADF host is bipolar, polarity differences still cause a mobility imbalance. In this work, we designed and synthesized a novel TADF host material, 11-(3-(4-(3-bromophenyl)-6-phenyl-1,3,5-triazin-2-yl)phenyl)-12,12-dimethyl-11,12-dihydroindeno[2,1-a]carbazole (Br-DMIC-TRZ). The upconversion of the TADF host and its doped films is facilitated due to enhanced spin-orbit coupling (SOC) induced by bromine, which exhibits a higher rate of RISC. This progress facilitates the involvement of more triplet excitons in luminescence. Meanwhile, the attachment of bromine to the acceptor fragment of TADF enhances the electron mobility, where hole mobility and electron mobility are more comparable. Enhanced exciton upconversion and balanced carrier transport allow devices formed based on brominated TADF hosts to outperform other hosts. The Br-TADF-based devices with three dopants sensitized achieved improvements of 29.8, 21.4, and 24.4% compared to the DMIC-TRZ-based device. This work provides a feasible molecular design strategy for further developing efficient hosts.

Tuning of the Singlet-Triplet Energy Gap of Donor-Linker-Acceptor Based Thermally Activated Delayed Fluorescent Emitters.

Thermally activated delayed fluorescent emitters based on carbazole donor, benzonitrile acceptor with the linkers biphenyl, bipyridine and naphthalene are investigated using the density functional theoretical method. The molecule in which bipyridine acts as the linker with the least ΔEST is further selected for the designing of a series of D-L-A framework TADF molecules. Remarkably, the ΔEST is decreased successively by attaching the additional cyano groups at the acceptor site which is further reduced when the electron donating methoxy groups are attached at the donor site. To know the effect of substituents on ΔEST, the acceptor moiety of the D-L-A framework is modified with -F, -Cl and -CF3 substituents. The studies showed a relatively less decrement in the value of ΔEST compared to the cyano substituted molecules. However, ΔEST significantly reduced further on attaching methoxy groups at the donor site.

A Rising Star: Luminescent Carbene-Metal-Amide Complexes.

Coinage metal (gold, silver, and copper) complexes are attractive candidates to substitute the widely studied noble metal complexes, such as, iridium(III) and platinum(II), as luminescent materials in organic light-emitting diodes (OLEDs). However, the development of coinage metal complexes exhibiting high emission quantum yields and short exciton lifetimes is still a formidable challenge. In the past few years, coinage metal complexes featuring a carbene-metal-amide (CMA) motif have emerged as a new class of luminescent materials in OLEDs. Thanks to the coinage metal-bridged linear geometry, coplanar conformation, and the formation of excited states with dominant ligand-to-ligand charge transfer character and reduced metal d-orbital participation, most CMA complexes have high radiative rates via thermally activated delayed fluorescence. Currently, the family of CMA complexes have rapidly evolved and remarkable progresses in CMA-based OLEDs have been made. Here, a Concept article on CMA complexes is presented, with a focus on molecular design principles, the correlation between molecular structure/conformation and optoelectronic properties, as well as OLED performance. The future prospects of CMA complexes are also discussed.

Macrocyclic Engineering of Thermally Activated Delayed Fluorescent Emitters for High-Efficiency Organic Light-Emitting Diodes.

Several thermally activated delayed fluorescence (TADF) materials have been studied and developed to realize high-performance organic light-emitting diodes (OLEDs). However, TADF macrocycles have not been sufficiently investigated owing to the synthetic challenges, resulting in limited exploration of their luminescent properties and the corresponding highly efficient OLEDs. In this study, a series of TADF macrocycles is synthesized using a modularly tunable strategy by introducing xanthones as acceptors and phenylamine derivatives as donors. A detailed analysis of their photophysical properties combined with fragment molecules reveals characteristics of high-performance macrocycles. The results indicate that: a) the ideal structure decreases the energy loss, which in turn reduces the non-radiative transitions; b) reasonable building blocks increase the oscillator strength providing a higher radiation transition rate; c) the horizontal dipole orientation (Θ) of the extended macrocyclic emitters is increased. Owing to the high photoluminescence quantum yields of ≈100% and 92% and excellent Θ of 80 and 79% for macrocycles MC-X and MC-XT in 5 wt% doped films, the corresponding devices exhibit record-high external quantum efficiencies of 31.6% and 26.9%, respectively, in the field of TADF macrocycles.

Curved Nanographenes: Multiple Emission, Thermally Activated Delayed Fluorescence, and Non-Radiative Decay.

The intriguing and rich photophysical properties of three curved nanographenes (CNG 6, 7, and 8) are investigated by time-resolved and temperature-dependent photoluminescence (PL) spectroscopy. CNG 7 and 8 exhibit dual fluorescence, as well as dual phosphorescence at low temperature in the main PL bands. In addition, hot bands are detected in fluorescence as well as phosphorescence, and, in the narrow temperature range of 100-140 K, thermally activated delayed fluorescence (TADF) with lifetimes on the millisecond time-scale is observed. These findings are rationalized by quantum-chemical simulations, which predict a single minimum of the S1 potential of CNG 6, but two S1 minima for CNG 7 and CNG 8, with considerable geometric reorganization between them, in agreement with the experimental findings. Additionally, a higher-lying S2 minimum close to S1 is optimized for the three CNG, from where emission is also possible due to thermal activation and, hence, non-Kasha behavior. The presence of higher-lying dark triplet states close to the S1 minima provides mechanistic evidence for the TADF phenomena observed. Non-radiative decay of the T1 state appears to be thermally activated with activation energies of roughly 100 meV and leads to disappearance of phosphorescence and TADF at T > 140 K.

Thermally activated delayed fluorescent small molecule sensitized fluorescent polymers with reduced concentration-quenching for efficient electroluminescence.

Thermally activated delayed fluorescence (TADF) small molecule bis-[3-(9,9-dimethyl-9,10-dihydroacridine)-phenyl]-sulfone (m-ACSO2) was used as a universal host to sensitize three conventional fluorescent polymers for maximizing the electroluminescent performance. The excitons were utilized via inter-molecular energy transfer and the non-radiative decays were successfully refrained in the condensed states. Therefore, the significant enhancement of the electroluminescent efficiencies was demonstrated. For instance, after doping poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT) into m-ACSO2, the external quantum efficiency (EQE) was improved by a factor of 17.0 in the solution-processed organic light-emitting device (OLED), as compared with the device with neat F8BT. In terms of the other well-known fluorescent polymers, i.e., poly (para-phenylene vinylene) copolymer (Super Yellow, SY) and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), their EQEs in the devices were respectively enhanced by 70% and 270%, compared with the reference devices based on the conventional host 1,3-di(9H-carbazol-9-yl) benzene (mCP). Besides the improved charge balance in the bipolar TADF host, these were partially ascribed to reduced fluorescence quenching in the mixed films.

Multi-Resonant Thermally Activated Delayed Fluorescent (MR-TADF) Compounds as Photocatalysts.

Donor-acceptor (D-A) thermally activated delayed fluorescent (TADF) compounds, such as 4CzIPN, have become a widely used sub-class of organic photocatalysts for a plethora of photocatalytic reactions. Multi-resonant TADF (MR-TADF) compounds, a subclass of TADF emitters that are rigid nanographene derivatives, such as DiKTa and Mes3 DiKTa, have to date not been explored as photocatalysts. In this study both DiKTa and Mes3 DiKTa were found to give comparable or better product yield than 4CzIPN in a range of photocatalytic processes that rely upon reductive quenching, oxidative quenching, energy transfer and dual photocatalytic processes. In a model oxidative quench process, DiKTa and Mes3 DiKTa gave increased reaction rates in comparison to 4CzIPN, with DiKTa being of particular interest due to the lower material cost (£0.94/mmol) compared to that of 4CzIPN (£3.26/mmol). These results suggest that DiKTa and Mes3 DiKTa would be excellent additions to any chemist's collection of photocatalysts.