Excess Defects Research Articles

Lithium-ion batteries pitch-based carbon anode materials: The role of molecular structures of pitches

To understand the effect of molecular configurations of coal tar pitch (CTP) on the reaction mechanism of carbonization and Li storage performance of subsequent carbonized products, four CTPs with different molecular structures are treated by liquid and solid phase carbonization and then tested the electrochemical performance of their carbonized products as anode materials for Lithium-ion batteries (LIBs). The results reveal that CTP-1 with hexagon rings, zigzag edges, and long alkyl side chains provides a large number of free radicals during pyrolysis, promoting the parallel arrangement of aromatic molecules. Special addition patterns (linear and nonlinear simultaneous) of aromatic molecular in CTP-3 generate a large number of edge carbons and surface defects in the carbonized products. The high viscosity and arm-chair edge reduce the reactivity of CTP-4 molecules, and the presence of loops and oxygenated aromatics in CTP-4 also reduces the orientation of carbon stacks and the flatness of the microstructure. The electrochemical performance of the final products shows a significant difference. Among them, CTP-1-M-1400 with a specific capacity of 349 mAh g−1 at 0.1 A g−1 displays an excellent cycling performance. Large amounts of Li-ions (about 39.2 %) are stored at the edge and surface of CTP-3-M-1400. While large number of Li-ions (about 23.5 %) are stored in the microspaces of CTP-4-M-1400. In addition, excessive structure defects and oxygen-containing groups in CTP-4-M-1400 lead to decreased capacity retention.

021. Outcomes of Adult Patients That Got Full Thickness Skin Graft with Skin Defects After the Surgical Wide Excision: Observational Case Series Study

Background: Full-thickness skin grafting plays an important role in reconstruction for excessive skin defects after the surgical wide excision. For closed defect consideration, full-thickness skin grafts can be used, The most common full-thickness skin graft donor sites include the retroauricular region, supraclavicular region, inguinal fold, buttock fold, hypothenar area, and anterior wrist fold. In this study. Methods: This is a single institutional, retrospective, observational case series study. We included 8 patients who underwent skin reconstruction using full-thickness skin grafts to close skin defects caused by the excision of skin tumor or trauma, between January 2024 and July 2024. Demographic data, including sex, age, location and photographs, and were collected. Results: the follow up for 8 patients that got full-thickness skin graft, we can make conclusion that full-thickness skin graft, can be the choice to closed the defect. The outcome of the patient is good with the defect is closed. Conclusion: Full-thickness skin grafting is a common technique for reconstructing skin defects after surgical wide excision. This case series demonstrates that using full-thickness grafts can effectively close these defects. Despite the challenges posed by the extent and location of the defects, the grafts provided a reliable solution when primary closure was not possible. Overall, this study highlights the importance of full-thickness skin grafting in the field of reconstructive surgery.

Erbium chloride‐mediated nucleation/crystallization control for high‐performance tin‐based perovskite solar cells

AbstractTin‐halide perovskite solar cells (THPSCs), while offering low toxicity and high theoretical power conversion efficiency, suffer from inferior device performance compared to lead‐based counterparts. The primary limitations arise from challenges in fabricating high‐quality perovskite films and mitigating the oxidation of Sn2+ ions, which leads to severe non‐radiative voltage losses. To address these issues, we incorporate the rare‐earth element erbium chloride (ErCl3) into PEA0.15FA0.70EA0.15SnI2.70Br0.30 perovskite to effectively control the nucleation and crystal growth, significantly influencing the morphology of the perovskite films. As a result, the ErCl3‐processed THPSC exhibits an impressive open‐circuit voltage (VOC) of 0.83 V and power conversion efficiency (PCE) of 14.0% with the superior light and air stability, compared to the control device (VOC = 0.77 V and PCE = 12.8%). This ErCl3‐strategy provides a feasible solution for high‐performance THPSCs by regulating nucleation/crystallization kinetics and mitigating excessive crystal defects during the preparation process of lead‐free perovskites.image

Enhanced energy storage performance of 0.85BaTiO3–0.15Bi(Mg0.5Hf0.5)O3 films via synergistic effect of defect dipole and oxygen vacancy engineering

Dielectric capacitors are widely used in electronic devices due to their ultra-fast charge/discharge rate and ultra-high power density, but their lower energy density and poor thermal stability limit their further application. In contrast to the traditional strategy of suppressing defects, this work combines oxygen vacancies with defect dipoles to improve the breakdown strength and polarization behavior of ferroelectric films. Low concentration of oxygen vacancies and defect dipoles can trap charge carriers and increase breakdown strength, but if the concentration is too high, it can easily make films prone to breakdown. Moreover, the defect dipoles can reduce Pr by providing intrinsic restoring force for polarization switching, while excessive defect dipoles and oxygen vacancies can pin domain walls and increase Pr. By delicately controlling the concentration of oxygen vacancies and defect dipoles in the film, the BT-BMH film deposited at 0.135 mbar achieved the maximum breakdown strength and slim P-E loops, inducing the energy density to reach 108.9 J·cm-3 with an efficiency of 79.6 % at room temperature and excellent thermal stability in the wide temperature range of -100∼350 °C with the energy density of 69.1 J·cm-3. This work reveals the important significance of reasonable defect control for improving energy storage performance and provides an effective method for developing high-performance dielectric capacitors.

Confinement Modulates Axial Patterning in Regenerating Hydra

The establishment of the body plan is a major step in animal morphogenesis. The role of mechanical forces and feedback in patterning the body plan remains unclear. Here we explore this question by studying regenerating Hydra tissues confined in narrow cylindrical channels, which constrain their morphology. We find that frustration between the orientation of the channel and the inherited axis in the regenerating tissues can lead to the formation of a multiaxial body plan. The morphological outcome is directly related to the pattern of nematic topological defects that emerges in the organization of the supracellular actomyosin fibers. When the inherited axis, which can be read out from the initial alignment of the supracellular fibers in the confined spheroid, is parallel to the channel's axis, the tissue regenerates normally into animals with a single body axis aligned with the channel. However, regenerating spheroids that are confined in a frustrated perpendicular configuration often develop excess defects (including negatively charged −1/2 defects) and regenerate into multiaxial morphologies. The influence of mechanical constraints on the regenerated body plan argues against an axial patterning mechanism that is based solely on inherited gradients of biochemical morphogens. We further show that the dependence of the regeneration outcomes on the initial tissue orientation can be recapitulated by a biophysical model, which considers the coupled dynamics of the nematic organization of the actomyosin fibers and a morphogen concentration field, incorporating a mechanochemical feedback loop involving strain-dependent morphogen production at defect sites. Published by the American Physical Society 2024

Low-pressure oxidation for improving interface properties and voltage instability of SiO2/4H-SiC MOS capacitor

The impact of high-temperature sub-atmospheric oxidation pressure on the interface properties of n-type 4H-SiC metal–oxide–semiconductor capacitors has been systematically investigated in this report. The bias temperature instability measurement was used to calculate the mobile ions and near-interface trap density that led to device instability at high temperatures. The density of near interface traps decreased from 88.3 × 1011 cm−2 to 10.2 × 1011 cm−2 when the growth pressure of SiO2 was reduced from 1 atm to 0.1 atm, while the mobile ions density decreased from 83.5 × 1011 to 4.18 × 1011 cm−2. The results show that SiO2 growing under lower oxidation pressure has better interfacial quality. The underlying mechanism was explored by secondary ion mass spectrometry (SIMS) and x-ray photoelectron spectroscopy (XPS). It is speculated that the SiO2/SiC interface was reconstructed under low-pressure oxidation: the excess Si-related defects near the interface, such as SiOxCy, were released while O atoms were accumulated to promote a complete oxidation reaction, thereby effectively reducing the number of defects in the SiO2 film and improving device performance.

Iodine‐Mediated Defect Engineering of Vanadyl Phosphate Cathodes for High‐Performance Aqueous Zinc‐Ion Batteries

AbstractVanadyl phosphate (VOPO4) is extensively studied as a cathode material for aqueous zinc‐ion batteries (AZIBs). However, due to sluggish ion migration and low electrical conductivity, VOPO4 typically exhibits moderate specific capacity below 200 mAh g−1. To address these issues, an iodine (I2)‐mediated etching method is proposed to enhance the electrochemical performance of VOPO4 for AZIBs. This method effectively regulates structural defects in VOPO4. Initially, I2 undergoes a disproportionation reaction with interlayer H2O in VOPO4, inducing crystal defects in the nanosheet structure. Additionally, the generated HI reduces V5+, further introducing oxygen vacancies in VOPO4. Both experimental and computational results indicate that moderate structural defects in VOPO4 can synergistically improve the electron transfer and ion diffusion kinetics of the electrode. However, excessive structural defects lead to crystalline amorphization and structural pulverization of VOPO4, impeding Zn2+ migration within the material. Therefore, the iodine‐mediated etched VOPO4 electrode (VOP‐I4) exhibits a high specific capacity of 249 mAh g−1 at a current density of 0.2 A g−1 and a large energy density of 300 Wh kg−1 at a power density of 246.2 W kg−1, outperforming most reported VOPO4‐based materials for AZIBs. This study provides a new avenue for developing high‐performance VOPO4 materials for energy storage applications.

Enhanced Stability Under Positive Bias Temperature Stress in Oxide Thin Film Transistors with Double Gate Structure By Improving Bottom Channel Interface

In this paper, we discuss the causes of reliability degradation in oxide TFTs with a double gate structure and propose methods for improvement. Reducing IGZO deposition power significantly improves PBTS (Positive Bias Temperature Stability) reliability in double gate structures. This improvement is attributed to reduction of excess oxygen defects accumulated at the bottom channel interface, as inferred from the difference in PBTS results for the top single gate and double gate structures

Defect-rich carbon nanosheets derived from p(C3O2)x for electromagnetic wave absorption applications

Defect modulation strategies have been shown to be an effective way to design efficient EMW absorbing materials, but the coexistence of multiple loss mechanisms due to the complexity of the existing models makes it difficult to elucidate the mechanism by which defect-induced dielectric losses dominate. In this work, p(C3O2)x is applied for the first time in the field of EMW absorption and the concentration of defects in the sample is controlled by changing the pyrolysis temperature. In addition, the unique molecular structure of p(C3O2)x enables the prepared samples to completely eliminate the interference of interfacial polarization and magnetic loss on EMW dissipation. The results show that the dielectric loss induced by defects significantly enhances the EMW absorption performance as the concentration of defects increases, but excessive defects lead to a sudden drop in the conductivity of the sample and reduce the EMW absorption performance. In which, the RLmin of OC-800 can reach −51.0 dB, and the EAB of OC-900 can go up to 5.6 GHz at only 1.6 mm. Finally, CST simulation verified the potential application of the prepared absorber in real scenarios. This work has improved the theoretical basis of the effect of defect-induced dielectric loss on EMW absorbing properties, and the simple synthetic raw materials and routes have made the industrialized production of highly efficient EMW absorbing materials possible.

Role of self-assembled molecules’ anchoring groups for surface defect passivation and dipole modulation in inverted perovskite solar cells

Abstract Inverted perovskite solar cells have gained prominence in industrial advancement due to their easy fabrication, low hysteresis effects, and high stability. Despite these advantages, their efficiency is currently limited by excessive defects and poor carrier transport at the perovskite–electrode interface, particularly at the buried interface between the perovskite and transparent conductive oxide (TCO). Recent efforts in the perovskite community have focused on designing novel self-assembled molecules (SAMs) to improve the quality of the buried interface. However, a notable gap remains in understanding the regulation of atomic-scale interfacial properties of SAMs between the perovskite and TCO interfaces. This understanding is crucial, particularly in terms of identifying chemically active anchoring groups. In this study, we used the star SAM ([2-(9H-carbazol-9-yl)ethyl] phosphonic acid) as the base structure to investigate the defect passivation effects of eight common anchoring groups at the perovskite–TCO interface. Our findings indicate that the phosphonic and boric acid groups exhibit notable advantages. These groups fulfill three key criteria: they provide the greatest potential for defect passivation, exhibit stable adsorption with defects, and exert significant regulatory effects on interface dipoles. Ionized anchoring groups exhibit enhanced passivation capabilities for defect energy levels due to their superior Lewis base properties, which effectively neutralize local charges near defects. Among various defect types, iodine vacancies are the easiest to passivate, whereas iodine-substituted lead defects are the most challenging to passivate. Our study provides comprehensive theoretical insights and inspiration for the design of anchoring groups in SAMs, contributing to the ongoing development of more efficient inverted perovskite solar cells.

Triple junction excess energy in polycrystalline metals

The energetics of triple lines are often negligible in polycrystalline systems, but may play a significant role in the finest nanocrystals, and in fact lower the excess defect energies of those polycrystals. This paper develops a methodology to assess polycrystalline average grain boundary and triple junction excess energies for pure fcc metals Ni, Cu, Al, Pd, Pt, Ag and Au using embedded atom method potentials. It is found that there are correlations between the triple line energy and physical quantities such as grain boundary and dislocation line energy, but with a negative sign indicating that triple junctions reduce intergranular excess energy per area on average. The relationship with grain boundary energy is of order ∼−4.5 × 10−10 m, and the triple junction energy is about −1/12 of the dislocation line energy. Despite their low energy, triple junctions can significantly affect total system energy due to their high density in the finest nanocrystals; for example, 6-nm Pd nanocrystals have an effective intergranular energy of ∼0.83 J/m2 (compared with the large grain size limit of 0.93 J/m2), translating to a measurable bulk excess enthalpy of ∼6 kJ/mol. Such excess enthalpy is experimentally assessable, and the present framework can be used to measure triple junction energies. For instance, re-analyzing data of Lu and Sun (Phil. Mag., 1997) we obtain grain boundary and triple junction energies of 0.33 J/m2 and −3.0 × 10−10 J/m respectively for Selenium nanocrystals, which can be compared with modeled values of 0.76 J/m2 and −1.02 × 10−10 J/m by using our method with a published bond-order potential for Se.

Comprehensive Review on Research Status and Progress in Precision Grinding and Machining of BK7 Glasses.

BK7 glass, with its outstanding mechanical strength and optical performance, plays a crucial role in many cutting-edge technological fields and has become an indispensable and important material. These fields have extremely high requirements for the surface quality of BK7 glass, and any small defects or losses may affect its optical performance and stability. However, as a hard and brittle material, the processing of BK7 glass is extremely challenging, requiring precise control of machining parameters to avoid material fracture or excessive defects. Therefore, how to obtain the required surface quality with lower cost machining techniques has always been the focus of researchers. This article introduces the properties, application background, machining methods, material removal mechanism, and surface and subsurface damage of optical glass BK7 material. Finally, scientific predictions and prospects are made for future development trends and directions for improvement of BK7 glass machining.

Fabrication of Micro‐Mesopores on Spiral Carbon Nanocoils and Simultaneous Doping with Oxygen to Expand Microwave Absorption Bandwidth

AbstractThe exceptional benefits of structural defects and doped atoms in carbon network regarding electromagnetic properties inspire the design of advanced carbon‐based microwave absorption (MA) materials. However, excessive structural defects decline the physical properties of materials, especially their conductivity. Therefore, it is a great challenge to balance structural defects and doped atoms to optimize conductive behavior for carbon‐based MA materials. The spiral carbon nanocoil (CNC), with coexisting amorphous and polycrystalline carbon structures and moderate conductivity, has significant MA properties but lacks pores and doped atoms. Herein, the amorphous carbon parts with relatively weak C─C bond energies are preferentially oxidized at 500 °C in air atmosphere to create pores and combine O atoms in the bodies of CNCs. Furthermore, the mechanism prioritizing the formation of O doping over defects is discovered. Benefiting from the synergistic interplay of structural defects and O dopants, the O‐enriched porous CNCs demonstrate enhanced conduction and polarization losses than the pure CNCs, realizing a wide effective absorption bandwidth of 7.3 GHz at a filling ratio of only 3 wt.%. Theoretical calculations further support these experimental results. The combination of structural defects and doped atoms may serve as an effective pathway for unlocking tunable dielectric properties of carbon‐based materials.

Unraveling the oxygen evolution in layered LiNiO2 with the role of Li/Ni disordering

Oxygen loss is widely recognized as a major factor in the structural degradation of Ni-rich layered cathode materials, while a study on the detailed oxygen evolution process and the role of inevitable Li/Ni disordering defects is still lacking. Using ab initio calculations with van der Waals correction, we performed an in-depth study on the oxygen evolution in layered LiNiO2 and considered the role of Li/Ni disordering. We find that excess Ni in Li slab act as a pillar role for the structural framework and increases bond strength of adjacent oxygen ions, both of which are beneficial to the thermal and kinetic stability of lattice oxygen in LiNiO2, thus inhibiting the oxygen evolution. For Li/Ni exchange and Excess Li defects, the Li ion in Ni slab preferred to return to the vacancy in Li slab with delithiation in both surface and bulk LiNiO2. This situation induces the weaken binding and fast migration of lattice oxygen, even Ni slab collapse and oxygen release in the surface. Furthermore, the ab-initio molecular dynamics simulations for LiNiO2 surface reveal three stages of oxygen loss in the pristine state: (i) the formation of pre-O-O dimer; (ii) the pre-O-O dimer oxidizing to O-O dimer; (iii) O2 release with oxygen oxidation and Ni migration. The Li/Ni exchange and Excess Li defects accelerate this process because of Li ion in Ni slab returning to Li slab, while the Excess Ni defects will inhibit this process. We hope this work will improve the understanding of oxygen evolution in layered LiNiO2 and provide theoretical guidance for the design of Ni-rich layered cathode materials with improved stability.

Defect induced Raman shifts and bandgap engineering in layered SnSe2+δ bulks

In the context of the extensive application prospect of two-dimensional (2D) chalcogenides, we synthesized layered SnSe2+δ bulks with defects employing a hybrid chemical vapor transport-melt approach. Both the Eg and A1g Raman characteristic peaks in SnSe2+δ are dominated by cubic anharmonicity, coupled with nonlinear temperature dependencies below 140 K. Notably, the reduction in phonon energy observed in these vibrational modes can be ascribed to defect-mediated Raman scattering, irrespective of deficient or excess Se defects. However, the lower consistency in the Raman shifts of the in-plane Eg vibrations compared to the out-of-plane A1g modes suggests that the defects predominantly entail the absence of Se atoms and the substitutions of Sn by Se, delineating a continuum of Se-deficient and Se-enriched compositions. Furthermore, Se defects induce the contraction of the indirect bandgaps, facilitating a transition from medium to narrow bandgap semiconductors in SnSe2+δ, which underscores the tunable nature of the bandgaps through the incorporation of Se defects. These discoveries present an avenue for bandgap engineering and foster a deeper comprehension of the phonon and thermal properties of layered chalcogenides for further advanced technologies.

Inspection of defects in composite structures using long pulse thermography and shearography

Long pulse thermography (LPT) and shearography have been developed as primary methods for detecting debonding or delamination defects in composites due to their full-field imaging, non-contact operation, and high detection efficiency. Both methods utilize halogen lamps as the excitation source for thermal loading. However, the defects detected by the two techniques differ due to their distinct inspection mechanisms. In this study, LPT and shearography are employed to evaluate internal damage in various composite structures. The experimental results demonstrate that LPT, when combined with thermal signal processing algorithms, can clearly detect debonding defects in rubber-to-metal bonded plates, whereas excessive adhesive defects can only be identified by shearography. Flat-bottom holes in the CFRP panel can only be detected by LPT, and shearography is particularly effective for detecting composite materials with a metal skin. For the quantitative measurement of defect sizes, the average errors of the rubber-to-metal bonded plate and CFRP panel using LPT are 4.9 % and 2.2 %, respectively, whereas the average errors of the rubber-to-metal bonded plate and aluminum honeycomb panel using shearography are 15.12 % and 95.4 %, respectively. This indicates that LPT is superior to shearography in quantitatively measuring defect sizes. These two nondestructive testing methods, based on different principles, each have their own advantages and disadvantages. Employing a multi-modal inspection method can leverage their complementary advantages, preventing misdetection and leakage of internal defects in composites.

Kibble-Zurek scalings and coarsening laws in slowly quenched classical Ising chains.

We consider a one-dimensional classical ferromagnetic Ising model when it is quenched from a low temperature to zero temperature in finite time using Glauber or Kawasaki dynamics. Most of the previous work on finite-time quenches assume that the system is initially in equilibrium and focuses on the excess mean defect density at the end of the quench, which decays algebraically in quench time with Kibble-Zurek exponent. Here we are interested in understanding the conditions under which the Kibble-Zurek scalings do not hold and in elucidating the full dynamics of the mean defect density. We find that depending on the initial conditions and quench time, the dynamics of the mean defect density can be characterized by coarsening and/or the standard finite-time quench dynamics involving adiabatic evolution and Kibble-Zurek dynamics; the timescales for crossover between these dynamical phases are determined by coarsening time and stationary state relaxation time. As a consequence, the mean defect density at the end of the quench either is a constant or decays following coarsening laws or Kibble-Zurek scaling. For the Glauber chain, we formulate a low-temperature scaling theory and find exact expressions for the final mean defect density for various initial conditions. For the Kawasaki chain where the dynamic exponents for coarsening and stationary state dynamics are different, we verify the above findings numerically and examine the effect of unequal dynamic exponents.

Rapid-thermal-process pre-treatment promoted precipitation towards strengthening hard magnetism of Sm2Co17-type magnets

Dislocations can act as heterogeneous nucleation sites but their annihilations upon heating sacrifice point defects nearby, weakening the driving force for precipitate nucleation. In order to keep a high density of dislocations and point defects together, here rapid-thermal-process (RTP) pre-treatment was carried out to promote the precipitate nucleation in Sm2Co17-type permanent magnets that evolve gradual formation and dissociation of dislocations during concurrent precipitation and recrystallization. As exhibited in a model magnet Sm25Co49.3Fe17.1Cu5.6Zr3.0 (wt.%) with high-density dislocations at solution-treated state, the RTP pre-treatment can induce excess point defects owing to the migration of solute atoms towards equilibrium state and the quenching of point defects, and suppress the early-stage diffusion-controlled dissociation of dislocations. After whole-process isothermal aging and slow cooling, the RTP pre-treated magnet possesses much higher fraction of hexagonal SmCo5 (1:5H) nanoprecipitates than the non-pre-treated one, giving rise to effective enhancements in coercivity Hcj from 26.20 to 30.34 kOe and in knee-point field Hk from 14.43 to 19.20 kOe. These findings add insight into controlling precipitation in dislocation-bearing supersaturated solid solutions, which are feasible for strengthening the Sm-Co-based magnets.

Analysis of Grindability and Surface Integrity in Creep-Feed Grinding of High-Strength Steels.

Creep-feed grinding of high-strength steel is prone to excessive wheel wear and thermal damage defects, which seriously affects the service performance of parts. To solve the above-mentioned issue, a creep-feed grinding test was carried out on high-strength steel using SG and CBN abrasive wheels. The grindability of high-strength steel was scrutinized in terms of grinding force, machining temperature and grinding specific energy. Moreover, the effects of operation parameters and grinder performances on the surface integrity of the workpiece such as surface morphology, roughness, residual stress and hardness were rigorously studied. The results indicate that, when the instantaneous high temperature in the grinding area reaches above the phase transition temperature of the steel, the local organization of the surface layer changes, leading to thermal damage defects in the components. The outstanding hardness and thermal conductivity of CBN abrasives are more productive in suppressing grinding burns than the high self-sharpening properties of SG grits and a more favorable machining response is achieved. The effects of thermal damage on the surface integrity of high-strength steel grinding are mainly in the form of oxidative discoloration, coating texture, hardness reduction and residual tensile stresses. Within the parameter range of this experiment, CBN grinding wheel reduces grinding specific energy by about 33% compared to SG grinding wheel and can control surface roughness below 0.8 µm. The weight of oxygen element in the burn-out workpiece accounts for 21%, and the thickness of the metamorphic layer is about 40 µm. The essential means of achieving burn-free grinding of high-strength steels is to reduce heat generation and enhance heat evacuation. The results obtained can provide technical guidance for high-quality processing of high-strength steel and precision manufacturing of high-end components.

An Efficient and Stable Inverted Structure Organic Solar Cell Using ZnO Modified by 2D ZrSe2 as a Composite Electron Transport Layer

AbstractAs an electron transport layer (ETL) widely used in organic solar cells (OSCs), ZnO has problems with energy level mismatch with the active layer and excessive defects on the ZnO surface, which can reduce the efficiency of OSCs. Here, ZnO/ZrSe2 composite is fabricated by modifying ZnO with 2D ZrSe2. The XPS and first‐principles calculation (FPC) show that ZnO obtains electrons from ZrSe2 and forms interfacial dipoles toward the active layer, which decreases the work function of ZnO, thus reducing the interface barrier and favoring the collection of electrons in OSCs. At the same time, after ZrSe2 modification, the oxygen vacancy density on the ZnO surface decreases, thus improving the conductivity of ZnO. More importantly, the femtosecond transient absorption (Fs‐TA) shows that ZrSe2 selectively traps holes from the active layer, which prevents the holes from entering the ZnO, thereby reducing the probability of electron recombination. Finally, ZnO/ZrSe2 composite is used as a novel ETL in OSCs with PBDB‐T: ITIC, PM6:Y6 and PM6: L8‐BO as active layers, and obtaining 12.09%, 16.34%, and 18.24% efficiency, respectively. This study provides a method for the interface modification of ZnO, and further investigates the role of 2D nanosheets in the interface modification.