Improved Charge Transport Research Articles

Revealing buried heterointerface energetics towards highly efficient perovskite solar cells

The heterointerfaces of charge-selective contacts are crucial in determining efficiency and stability of perovskite optoelectronic devices, where the fundamental knowledge of the buried heterointerface between perovskite and bottom charge transport layer is less well understood compared to the top interface. Herein, we systematically investigate the energetics at the perovskite/SnO2 buried heterointerface for an n-i-p perovskite solar cell (PSC) and the perovskite/PEDOT:PSS buried heterointerface for a p-i-n one, respectively. In contrast to previous cognitions, we discover a perovskite transition phase at the buried interface region that originates from the chemical bonding interaction with the bottom charge transport layer. The transition phase causes an energy level barrier and induces defects, impeding charge transport across the heterointerface. These detrimental effects trigger significant nonradiative recombination and limit the attainable device photovoltage. We then develop the energetic models that describe such buried heterointerfaces. Moreover, we further test the proposed model-derived mechanisms via inserting a thin polyvinyl alcohol layer into the buried heterointerfaces of the devices. We demonstrate that chemical interactions and formation of the perovskite transition phase at the buried heterointerface thereby are fully restrained, leading to a diminished electron extraction barrier and improved charge transport. As a result, significant increases in open-circuit voltage and fill factor of the devices are achieved. These results will help guide future efforts on developing suitable buried heterointerfaces for superior performance of perovskite optoelectronics.

Facile and Effective Band Gap Engineering of 2D Ruddlesden–Popper Perovskites with Improved Structural and Optoelectronic Properties

Incorporation of alkali metal ions (Li+, Na+, K+, Rb+, and Cs+) into 3D metal-halide perovskite crystal structures has resulted in improved crystallinity and film morphology, reduced trap density, and enhanced charge carrier transport. However, due to intrinsic structural instability associated with 3D perovskites, their alkali metal ion-doped semiconductors are not a suitable option for real device optoelectronics. In recent years, Ruddlesden–Popper (RP)-phase quasi-two-dimensional (2D) metal halide perovskites have drawn considerable attention due to their tunable energy band gap, large electron and hole diffusion lengths (∼10 μm), and lower recombination rates compared to pristine 2D metal halide perovskites (n = 1). However, alkali metal ion-incorporated RP perovskite systems are not explored much; therefore, we demonstrate the incorporation of Rb+, using the RbI precursor, into the quasi-2D RP perovskite (BA)2(MA)Pb2Br7 (BA = C4H9NH3; MA = CH3NH3), which has also resulted in the successive replacement of Br– with I– in the PbBr6 network. Subsequent replacement of Br– with I– finely tuned the energy band gap from 2.92 to 2.43 eV, while keeping the phase of the pristine lead bromide RP perovskite intact, as confirmed by X-ray diffraction investigations. MA+ cations available at the outer edge sites got partially exchanged with Rb ions, which in turn has regulated the perovskite crystal growth, whereas the excess Rb+ alloyed with replaced Br– to form RbBr, which resulted in the formation of thinner grain boundaries and thus showed improved charge transport. Transient photocurrent measurements performed for RbI-doped perovskites (lateral configuration photodetector: fluorine-doped tin oxide (FTO)/RP-perovskite/FTO of channel width ∼150 μm), for 35 cycles under standard Xe-lamp (100 mW/cm2) illumination, have shown strong and fast photocurrent response with large photoresponsivity (3.92 × 10–4 A/W). Comparison of structural, optical, and optoelectronic properties of RbI-doped RP perovskites is carried out with the mixed RP perovskites and has further confirmed that Rb+ incorporation plays an important role in enhancing the crystal growth.

Linear-Shaped Low-Bandgap Asymmetric Conjugated Donor Molecule for Fabrication of Bulk Heterojunction Small-Molecule Organic Solar Cells.

A linear-shaped small organic molecule (E)-4-(5-(3,5-dimethoxy-styryl)thiophen-2-yl)-7-(5″-hexyl-[2,2':5',2″-terthiophen]-5-yl)benzo[c][1,2,5]thiadiazole (MBTR) comprising a benzothiadiazole (BTD) acceptor linked with the terminal donors bithiophene and dimethoxy vinylbenzene through a π-bridge thiophene was synthesized and analyzed. The MBTR efficiently tuned the thermal, absorption, and emission characteristics to enhance the molecular packing and aggregation behaviors in the solid state. The obtained optical bandgap of 1.86 eV and low-lying highest occupied molecular orbital (HOMO) level of -5.42 eV efficiently lowered the energy losses in the fabricated devices, thereby achieving enhanced photovoltaic performances. The optimized MBTR:PC71BM (1:2.5 w/w%) fullerene-based devices showed a maximum power conversion efficiency (PCE) of 7.05%, with an open-circuit voltage (VOC) of 0.943 V, short-circuit current density (JSC) of 12.63 mA/cm2, and fill factor (FF) of 59.2%. With the addition of 3% 1,8-diiodooctane (DIO), the PCE improved to 8.76% with a high VOC of 1.02 V, JSC of 13.78 mA/cm2, and FF of 62.3%, which are associated with improved charge transport at the donor/acceptor interfaces owing to the fibrous active layer morphology and favorable phase separation. These results demonstrate that the introduction of suitable donor/acceptor groups in molecular design and device engineering is an effective approach to enhancing the photovoltaic performances of organic solar cells.

Elucidating the Origins of High Preferential Crystal Orientation in Quasi‐2D Perovskite Solar Cells (Adv. Mater. 5/2023)

Perovskite Solar Cells In article 2208061, Lukas E. Lehner, Martin Kaltenbrunner, and co-workers report the controlled nucleation of quasi-2D perovskites at the liquid–air interface of the precursor solution. Restricting the initial crystal growth to the surface of the liquid results in highly aligned perovskite thin films with improved charge transport, enabling efficient solar cells with excellent stability.

Oxidized Carbon Materials as Hole Transport Layers for High‐Performance Organic Photovoltaics

Flexible Organic Photovoltaics In article number 2200908, Dong-Yu Kim and co-workers introduced an oxidized carbon soot (OCS)-based hole-transporting layer to improve charge transport without charge recombination, finally enhancing the device performance up to 15.04%. Due to the functionalization of OCS with octadecylamine, the largesized and flexible organic photovoltaics prepared by blade coating exhibited high storage stability (71% retention) and mechanical stability (78% retention).

Dual-functional electrostatic self-assembly nanoparticles enable suppressed defects and improved charge transport in perovskite optoelectronic devices

The performance of perovskite solar cells and photodetectors strongly depends on the carrier extraction in the electron transport layer/perovskite interface and the film quality of the perovskite layer. Ti3C2Tx MXene quantum dots, which exhibit both good conductivity of MXene materials and size-dependent tunable optoelectronic properties of quantum dots, were synthesized to form electrostatic self-assembly nanoparticles and further introduced into perovskite optoelectronic devices. The carrier extraction in electron transport layer/perovskite interface was significantly improved, and the defect density of the modified perovskite layer was effectively reduced. These improvements ultimately lead to a remarkable power conversion efficiency of perovskite solar cells increasing from 16.57 % to 23.47 %, and the photodetectors achieve responsivity approaching 35.54 mA W−1 and response speed of 154 ms (rise time) and 120 ms (decay time). Meanwhile, the long-time humidity, thermal and light stress stability of the devices were largely boosted, which originated from the better crystallization and suppressed degradation of the perovskite films.

Z-scheme WOx/Cu-g-C3N4 heterojunction nanoarchitectonics with promoted charge separation and transfer towards efficient full solar-spectrum photocatalysis

Construction of Z-scheme heterojunctions has been considered one superb method in promoting solar-assisted charge carrier separation of carbon-based materials to achieve efficient utilization of solar energy in hydrogen production and CO2 reduction. One interesting concept in nanofabrication that has become trend recent years is nanoarchitectonics. A heterostructure photocatalyst constructed based on the idea of nanoarchitectonics using the combination of g-C3N4, metal and an additional semiconducting nanocomposite is investigated in this paper. Z-scheme tungsten oxide incorporated copper modified graphitic carbon nitride (WOx/Cu-g-C3N4) heterostructures are fabricated via immobilization of WOx on Cu nanoparticles modified superior thin g-C3N4 nanosheets. Mechano-chemical pre-reaction and a two-step high-temperature thermal polymerization process are the keys in attaining homogeneous distribution of Cu nanoparticles in g-C3N4 nanosheets. The horizontal growth of homogeneously distributed WOx nanobelts on Cu modified g-C3N4 (Cu-g-C3N4) base via solvothermal synthesis is achieved. The photocatalytic performances of the heterostructures are evaluated through water splitting and CO2 photoreduction measurements in full solar spectrum irradiation condition. The presence of Cu nanoparticles in the composite system improves charge transport between g-C3N4 and WOx and thus enhances the photocatalytic performances (H2 generation and CO2 photoreduction) of the composite material, while the presence of WOx nanocomposites enhances light absorption of the composite material in the near infrared range. The synthesized heterostructure with optimized WOx to Cu-g-C3N4 ratio and in case of no co-catalyst addition exhibits enhanced photocatalytic H2 evolution (4560 μmolg-1h−1) as well as excellent CO2 reduction rate (5.89 μmolg-1h−1 for CO generation).

Extending the Absorption Spectra and Enhancing the Charge Extraction by the Organic Bulk Heterojunction for CsPbBr3 Perovskite Solar Cells

Among the various lead halide perovskites, inorganic cesium lead bromide (CsPbBr3) was considered as a promising candidate for new solar cells because of its unique photophysical properties and outstanding stabilities in a high-humidity, high-temperature, or ambient atmosphere. However, the efficiency is still quite limited due to the inefficient charge transfer and narrow spectra. In this work, we report that integrating the P3HT/PCBM bulk heterojunction (BHJ) organic layer with the CsPbBr3 films can sharply enhance the spectral absorption from 540 to 680 nm and simultaneously enhance the charge extraction ability at the CsPbBr3/carbon interface. At the same time, the carbonyl group and thiophene units in the BHJ group can inhibit the production of Pb0 defects and passivate the under-coordinated Pb2+, thus reducing trap density, retarding charge recombination, and improving charge transport and extraction. Using this strategy, the efficiency of BHJ/CsPbBr3 solar cells is improved from 5.36 to 8.15%. In addition, the integrated devices have superior long-term stability, and unpackaged devices can maintain an initial efficiency of 90% within 40 days. This work provides an avenue for the industrial application of this integrated device in the future.

Preferred Acceptor-Domain Positioning via a Phase-Switched Bulk Heterojunction for Self-Powered Photodetector and Photovoltaic Applications

In this study, a phase-switching process is introduced to a PM6:Y6-based active layer to implement a uniform surface with preferred Y6 acceptor-domain positioning and to minimize solution loss owing to the use of medium molds. By designing the process to fit the surface properties of a small-molecule Y6 acceptor-based bulk heterojunction, a sustainable and highly reproducible phase-switched active layer that can be formed at the desired location without wasting materials is successfully formed over an area of 2.25 cm2. It improved charge transport ability and suppressed surface defects owing to a molecular orientation favorable for efficient charge separation and transport. Furthermore, adding chloronaphthalene induced the domain growth of Y6 acceptors with dense molecular packing, which enhanced the effects of the phase-switching process. Uniformly distributed performance in the phase-switched active layer via the phase-switching process was demonstrated in fabricated large active-area devices. Furthermore, the process was utilized in a PM6:Y6-based self-powered photodetector, which improved detectivity owing to the suppression of the dark current density. Therefore, the phase-switching process is an important technology for forming high-quality thin films composed of small-molecule acceptors for efficient self-powered photodetector and photovoltaic applications.

High-Throughput Strategies for the Design, Discovery, and Analysis of Bismuth-Based Photocatalysts.

Bismuth-based nanostructures (BBNs) have attracted extensive research attention due to their tremendous development in the fields of photocatalysis and electro-catalysis. BBNs are considered potential photocatalysts because of their easily tuned electronic properties by changing their chemical composition, surface morphology, crystal structure, and band energies. However, their photocatalytic performance is not satisfactory yet, which limits their use in practical applications. To date, the charge carrier behavior of surface-engineered bismuth-based nanostructured photocatalysts has been under study to harness abundant solar energy for pollutant degradation and water splitting. Therefore, in this review, photocatalytic concepts and surface engineering for improving charge transport and the separation of available photocatalysts are first introduced. Afterward, the different strategies mainly implemented for the improvement of the photocatalytic activity are considered, including different synthetic approaches, the engineering of nanostructures, the influence of phase structure, and the active species produced from heterojunctions. Photocatalytic enhancement via the surface plasmon resonance effect is also examined and the photocatalytic performance of the bismuth-based photocatalytic mechanism is elucidated and discussed in detail, considering the different semiconductor junctions. Based on recent reports, current challenges and future directions for designing and developing bismuth-based nanostructured photocatalysts for enhanced photoactivity and stability are summarized.

Strong Magnetic Field Annealing for Improved Phthalocyanine Organic Thin-Film Transistors.

Thin-film microstructure, morphology, and polymorphism can be controlled and optimized to improve the performance of carbon-based electronics. Thermal or solvent vapor annealing are common post-deposition processing techniques; however, it can be difficult to control or destructive to the active layer or substrates. Here, the use of a static, strong magnetic field (SMF) as a non-destructive process for the improvement of phthalocyanine (Pc) thin-film microstructure, increasing organic thin-film transistor (OTFTs) mobility by twofold, is demonstrated. Grazing incident wide-angle X-ray scattering (GIWAXS), X-ray diffraction (XRD), and atomic force microscopy (AFM) elucidate the effect of SMF on both para- and diamagnetic Pc thin-films when subjected to a magnetic field. ASMF is found to increase the concentration of oxygen-induced radical species within the Pc thin-film, lending a paramagnetic character to ordinarily diamagnetic metal-free Pc and resulting in magnetic field induced changes to its thin-film microstructures. In a nitrogen environment, without competing degradation effects of molecular oxygen, SMF processing is found to favorably improve charge transport characteristics and increase OTFT mobility. Thus, post-deposition thin-film annealing with a magnetic field is presented as an alternative and promising technique for future thin-film engineering applications.

17% efficiency for linear-shaped ADA-type nonfullerene acceptors enabled by 3D reticulated molecular packing

The fundamental principles governing photovoltaic properties of nonfullerene acceptors (NFAs) are essential for developing high-performance polymer solar cells. In this work, using three heteroheptacene-based acceptors (M-series) as model compounds, we systematically study the implication of heteroatoms in the heteroheptacene core on the molecular packing, morphology, optoelectronic, photophysical, and photovoltaic properties of the NFAs. It is found that replacing the oxygen atoms at the inner positions of the heteroheptacene core with sulfur atoms leads to the molecular packing mode change from a linear two-dimensional (2D) brickwork structure to a three-dimensional (3D) reticulated motif, which facilitates the formation of a desirable active layer with nanostructured phase separation morphology and improved charge transport. Meanwhile, the down-shifted highest occupied molecular orbital energy level of M36 induced by the sulfur substitution, matches better with that of polymer donor PM6 thereby leading to more efficient exciton dissociation and charge transfer. As a result, the best-performing photovoltaic device based on M36 affords an outstanding efficiency of 17%, which is among the highest values reported for all the ADA-type NFAs. Our work reveals the important role of the heteroatoms in the heteroheptacene core in constructing the 3D network of ADA-type NFAs, and the structure-property relationships herein shall provide an important guidance for designing high-performance NFAs.

Improved charge transport through 2D framework in fully condensed carbon nitride for efficient photocatalytic hydrogen production

The 1D molecular structure of traditional graphitic carbon nitride (GCN) leads to the space-confined transport of charge carriers along the chains and prohibits transport across the chains. Therefore, the formation of 2D network which can provide more convenient transfer paths is of great desirable. In this work, a fully condensed carbon nitride with the real 2D framework was successfully developed by post-calcining 1D GCN in a LiCl/KCl molten salt. The newly formed 2D molecular structure significantly promoted the charge transfer and separation, resulting in remarkably enhanced photocatalytic hydrogen production activity. Moreover, N-doped graphene quantum dots (NGQDs) incorporation can be simultaneously realized via the simple one step “co-dissolution and recrystallization” method. Especially, the as-prepared 2D-CN/NGQDs sample presents a further increased photocatalytic hydrogen evolution rate up to about 30 times that of pristine GCN. The apparent quantum efficiency (AQE) for H2 evolution of 2D-CN/NGQDs reaches 36 % at 420 nm.

A Polyfluoroalkyl-Containing Non-fullerene Acceptor Enables Self-Stratification in Organic Solar Cells.

The elaborate control of the vertical phase distribution within an active layer is critical to ensuring the high performance of organic solar cells (OSCs), but is challenging. Herein, a self-stratification active layer is realised by adding a novel polyfluoroalkyl-containing non-fullerene small-molecule acceptor (NFSMA), EH-C8 F17 , as the guest into PM6:BTP-eC9 blend. A favourable vertical morphology was obtained with an upper acceptor-enriched thin layer and a lower undisturbed bulk heterojunction layer. Consequently, a power conversion efficiency of 18.03 % was achieved, higher than the efficiency of 17.40 % for the device without EH-C8 F17 . Additionally, benefiting from the improved charge transport and collection realised by this self-stratification strategy, the OSC with a thickness of 350 nm had an impressive PCE of 16.89 %. The results of the study indicate that polyfluoroalkyl-containing NFSMA-assisted self-stratification within the active layer is effective for realising an ideal morphology for high-performance OSCs.

A Polyfluoroalkyl‐Containing Non‐fullerene Acceptor Enables Self‐Stratification in Organic Solar Cells

AbstractThe elaborate control of the vertical phase distribution within an active layer is critical to ensuring the high performance of organic solar cells (OSCs), but is challenging. Herein, a self‐stratification active layer is realised by adding a novel polyfluoroalkyl‐containing non‐fullerene small‐molecule acceptor (NFSMA), EH‐C8F17, as the guest into PM6:BTP‐eC9 blend. A favourable vertical morphology was obtained with an upper acceptor‐enriched thin layer and a lower undisturbed bulk heterojunction layer. Consequently, a power conversion efficiency of 18.03 % was achieved, higher than the efficiency of 17.40 % for the device without EH‐C8F17. Additionally, benefiting from the improved charge transport and collection realised by this self‐stratification strategy, the OSC with a thickness of 350 nm had an impressive PCE of 16.89 %. The results of the study indicate that polyfluoroalkyl‐containing NFSMA‐assisted self‐stratification within the active layer is effective for realising an ideal morphology for high‐performance OSCs.

Strain-regulated electronic properties of helical polymer with phenylacetylene monomers—a first principle study

Helical polymers, a class of organic polymers with a unique spring-like structure, possess interesting electronic configurations and axial quantum transport properties thanks to the tunable interlayer electronic interaction by strain engineering. In this report, we carried out first-principle calculations to investigate the electronic structures and transport properties of the helical polymer with phenylacetylene monomers under compressive strains. The band structures of the material show a remarkable semiconductor-to-metal phase transition and enhanced electronic dispersion caused by the great interlayer coupling when subjected to an increasing compressive strain. During compression, the conduction band minimum and valence band maximum gradually move closer to the Fermi level and eventually pass through the Fermi surface. Moreover, under large strains, a notable overlap between interlayer electron clouds makes an effective channel for the axial electron transmission, explaining the greatly improved charge transport properties. This improvement is mainly due to the formation of the interlayer transmission channels through σ bonds. Our findings on the strain-regulated electronic properties of helical polymers suggest there are great potential applications of these materials in high-performance sensors and flexible electronic devices.

One-step synthesis of low-cost perylenediimide-based cathode interfacial materials for efficient inverted perovskite solar cells

Interface engineering plays an important role in improving the performance of perovskite devices. Herein, we reported two perylenediimide small molecular cathode interface materials (CIMs), PDI-2N and PDI-4N, synthesized by a simple method and with good alcohol soluble, which could be used as cathode interfacial layer (CIL) for high-performance inverted perovskite solar cells (PVSCs). The PDI-4N exhibits larger electrical conductivity, electron mobility and self-doping properties than PDI-2N because of more dimethylamino functional groups in the amide positions. Based on these superiorities, a peak PCE of 21.33% with PDI-4N as CIL was achieved, which is the highest PCE for PDI-based interlayer materials as the cathode interlayer in inverted PVSCs. While the PCE with PDI-2N as CIL is only 17.41%. The significant improvement in device efficiency for PDI-4N based device is due to reduced defect density, lower dark current, larger recombination resistance and better surface morphology, which improved charge transport and collection at the PC61BM/Ag interface. Moreover, the ambient stabilities of PVSCs with PDI-2N and PDI-4N as CIL show that the CILs can effectively improve the device stability, and good stability with a PCE loss of only ∼3.0% after 600 h is also obtained. In a word, this work will provide us with molecular design approach by one-step to develop novel cathode interface materials with functional side chains for high-efficiency PVSCs.

Photo-induced charge transfer in composition-tuned halide perovskite nanocrystals with quinone and its impact on conduction current

A facile interfacial charge transfer (CT) with a reduced inter-layer energy band regulates the charge transport mechanism in any optoelectronic device. The enhancement in semiconductor-based device performance often demands improved CT dynamics and collection of free carriers with reduced charge recombination. In this work, we present a detailed inspection of the photo-induced CT between inorganic lead halide perovskite nanocrystals (PNCs) with varied compositions and their consequence on the charge transport process. The superior CT rate in mixed halide CsPbBr2Cl PNCs with naphthoquinone (NPQ) is revealed when compared with the parent CsPbBr3 PNCs and its anion-exchanged counterpart CsPbCl3. The glimpses of hole transfer contribution along with electron transfer are detected for CsPbBr2Cl with superior CT efficiency. The enhanced conduction current after the insertion of NPQ into the PNCs with a reduced hysteresis suggests an improved charge transport in the fabricated device compared to the pristine PNCs. These findings can contribute to a better understanding of multiple ways of engineering optoelectronic devices to boost performance and efficiencies and the concurrent role of the CT process in the conduction mechanism.

Fabrication of dual Z-scheme g-C3N4/Fe2TiO5/Fe2O3 ternary nanocomposite using natural ilmenite for efficient photocatalysis and photosterilization under visible light

The advanced oxidation process is a prominent method available to remove dyes released to normal water reservoirs to alleviate water scarcity. We report the fabrication of novel g-C3N4/Fe2TiO5/Fe2O3 using natural ilmenite sand as the precursor of the metallic semi-conductors exploration of a heterostructure for photodegradation of methylene blue under sunlight. Ternary composites were synthesized by varying g-C3N4 with respect to Fe2TiO5/Fe2O3 and varying Fe2TiO5/Fe2O3 with respect to g-C3N4 where the varying component was varied as 8, 24 and 40%, respect to the constant material. The hybridization of the three semi-conductors has been confirmed by the microscopic, chemical, and structural analyses. X-ray diffraction patterns show the presence of all three g-C3N4, Fe2TiO5 and α-Fe2O3 while the transmission electronic microscopic and scanning electronic microscopic images show the heterogeneous distribution of the metal oxide nanoparticles on g-C3N4 matrix forming the composite. HRTEM images further reveal the junction of Fe2TiO5 and α-Fe2O3. X-ray photoelectron spectra show the existence of s-triazine and heptazine rings in the composites with Fe3+ and Ti4+ as the only oxidation states of Fe and Ti. Fe2TiO5/Fe2O3/40% g-C3N4 with bandgap of 2.63 eV calculated by diffuse reflectance UV-Visible spectroscopy showed the highest photocatalytic activity (0.009 min−1) being 1.3 times greater than the Fe2TiO5/Fe2O3 nanoparticles. Enhanced photocatalytic activity over the fabricated composites was observed due to the increased visible light absorption, efficient charge separation and improved charge transportation. g-C3N4 coupled with 40% Fe2TiO5/Fe2O3 showed the highest antibacterial activity against gram-negative E.Coli. The synthesis of dual Z-scheme g-C3N4/Fe2TiO5/Fe2O3 ternary composite provides new sights in developing novel photocatalysts using natural ilmenite sand for environmental applications.

Fabrication of ZnO dual electron transport layer via atomic layer deposition for highly stable and efficient CsPbBr3 perovskite nanocrystals light-emitting diodes

Electron transport layers (ETLs) are important components of high-performance all-inorganic perovskite nanocrystals light-emitting diodes (PNCs-LED). Herein, atomic layer deposition (ALD) of inorganic ZnO layer is combined to the organic 1,3,5-Tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi) to form dual ETLs to enhance both the efficiency and stability of PNCs-LED simultaneously. Optimization of ZnO thickness suggested that 10 cycles ALD yields the best performance of the devices. The external quantum efficiency of the device reaches to 7.21% with a low turn-on voltage (2.4 V). Impressively, the dual ETL PNCs-LED realizes maximum T 50 lifetime of 761 h at the initial luminance of 100 nit, which is one of the top lifetimes among PNCs-LEDs up to now. The improved performance of dual ETL PNCs-LED is mainly due to the improved charge transport balance with favorable energy level matching. These findings present a promising strategy to modify the function layer via ALD to achieve both highly efficient and stable PNCs-LED.