This review gives an overview of the recent advances of metal-containing organic compounds in memory and data storage applications. The challenges and future research directions of the field are also discussed.

To study the influence of different types of substituent moieties onto the molecular backbones of conjugated donor–acceptor (D–A) molecules on the thin‐film morphology and performance of their memory devices, three new molecules X‐TBT were synthesized, which consist of the same backbone of two triphenylamine (T) groups and benzothiadiazole (BT) group, but have different substituents (X) with different electronic effects, that is, cyano group (CN), tert‐butyl group (tBu), and methoxy group (OMe). Nonvolatile ternary write‐once‐read‐many‐times (WORM) data storage behavior is achieved for the CN‐TBT and tBu‐TBT based devices as compared to the binary memory characteristic of TBT (X = H). In contrast, OMe‐TBT based device still maintains binary WORM behavior due to its unfavorable molecular packing motif and weak intermolecular charge transfer effect, but exhibits the lowest operating voltage (1.4 V) as a result of the lowest energy barrier between electrode and active layer. Notably, the tBu‐TBT based device displays the highest ION2/ION1/IOFF ratio of 107:103:1. Altering the substituents in D–A molecules can adjust the molecular packing, thin film morphology, and electron trap depth of the active layer, which then significantly influence the memory performance.

A significant enhancement in ultraviolet (UV) durable indium tin oxide (ITO)-free flexible nonfullerene organic solar cells (OSCs) has been demonstrated using a hybrid nanostructured flexible transparent electrode (FTE), comprising a mixture of 0D silver nanoparticles (AgNPs), 1D Ag nanowires (AgNWs) and 2D exfoliated graphene sheets. The FTE exhibits high optical transparency and electric conductivity, good air stability and full-solution fabrication capability at a low processing temperature. An average power convention efficiency (PCE) of 8.15% has been obtained for the flexible nonfullerene OSCs, based on the blend of poly[(2,6-(4, 8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thi enyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c'] dithiophene-4,8-dione)] (PBDB-T): 3,9bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dit hieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b'] dithiophene (ITIC). The flexible PBDB-T:ITIC OSCs exhibit an excellent UV durability compared to the ITO-based control cell, realized by the tailored FTE absorption in wavelength < 380 nm. The novel FTE developed in this work provides a promising alternative to ITO for use in UV durable flexible OSCs, serving as a UV filter to impede an unavoidable UV-induced degradation in ITO-based OSCs.

Niobium‐carbide (Nb2C) MXene as a new 2D material has shown great potential for application in photovoltaics due to its excellent electrical conductivity, large surface area, and superior transmittance. In this work, a novel solution‐processable poly(3,4‐ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS)‐Nb2C hybrid hole transport layer (HTL) is developed to enhance the device performance of organic solar cells (OSCs). By optimizing the doping ratio of Nb2C MXene in PEDOT:PSS, the best power convention efficiency (PCE) of 19.33% can be achieved for OSCs based on the ternary active layer of PM6:BTP‐eC9:L8‐BO, which is so far the highest value among those of single junction OSCs using 2D materials. It is found that the addition of Nb2C MXene can facilitate the phase separation of the PEDOT and PSS segments, thus improving the conductivity and work function of PEDOT:PSS. The significantly enhanced device performance can be attributed to the higher hole mobility and charge extraction capability, as well as lower interface recombination probabilities generated by the hybrid HTL. Additionally, the versatility of the hybrid HTL to improve the performance of OSCs based on different nonfullerene acceptors is demonstrated. These results indicate the promising potential of Nb2C MXene in the development of high‐performance OSCs.

In this paper, we demonstrate a solution-processed MoSe2 Quantum Dots/PEDOT:PSS bilayer hole extraction layer (HEL) for non-fullerene organic solar cells (OSCs). It is found that introduction of MoSe2 QDs can...

All-solution-processed flexible organic solar cells (FOSCs) with high power conversion efficiency (PCE) are the prerequisite for application in low-cost, large-area, flexible, photovoltaic devices. In this work, high-performance, top-illuminated FOSCs using ultrathin Ag-modified graphite-coated poly(ethylene terephthalate) (PET) substrates are demonstrated. The ultrathin Ag-modified graphite/PET substrates have excellent electric conductivity, mechanical flexibility, and easy processability for FOSCs. A PCE of 5.31% for FOSCs, based on the blend system poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo [1,2-b:4,5-b′]dith-iophene-co-3-fluorothieno[3,4-b]thiophene-2-carboxylate]: [6,6]-phenyl-C7l-but-yric acid methyl ester, having a bilayer of MoOx/Ag upper transparent anode is demonstrated. Top-illuminated FOSCs with a transparent upper electrode of solution-processed Ag nanowires also yielded a PCE of 3.76%. All-solution-processed FOSCs exhibit excellent mechanical flexibility and retain >81% of the initial efficiency after 500 cycles of bending test. Furthermore, graphite-based electrodes demonstrate good heat-insulation properties. The outcomes of this work offer an alternative to fabricate high-performance, all-solution-processable, top-illuminated FOSCs, providing a commercially viable approach for application in large-area solar cells that can be prepared by printing and roll-to-roll fabrication processes.

High performance Alq3-based organic light emitting diodes are achieved by using magnetic nanoparticles/poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) as the composite hole-injection layer through the advantageous combination of light-scattering, localized surface plasmon resonance and magnetic effect.

A significant enhancement in light extraction in organic light-emitting diodes (OLEDs) is realized by using composite hole transport layers (HTLs) with surface carbon-coated magnetic alloy nanoparticles (NPs). Compared to the control device with a standard architecture, the current efficiencies of fluorescent green OLEDs can be enhanced by 47.1% and 48.5% by mixing the surface carbon-coated magnetic FePt (0.5 wt‰) and CoPt (0.5 wt‰) alloy NPs into poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), yielding the maximum values of 5.40 cd A and 5.45 cd A, respectively. The presence of an alloy NP-incorporated PEDOT:PSS HTL also acts as an optical out-coupling layer contributing to the efficiency enhancement, accomplished through the collective effects of light-scattering, localized surface plasmon resonance and increased electron trap density induced by magnetic alloy NPs.