Achieving high-quality perovskite films without surface defects is regarded as a crucial target for the development of durable high-performance perovskite solar cells.Additive engineering is commonly employed to simul...Achieving high-quality perovskite films without surface defects is regarded as a crucial target for the development of durable high-performance perovskite solar cells.Additive engineering is commonly employed to simultaneously control the growth of perovskite crystals and passivate defects.Here,4-(trifluoromethyl)benzoic anhydride(4-TBA)composed of benzene rings functionalized with carbonyl and trifluoromethyl groups was used as an example additive to study the characteristics of additives used for producing high-quality perovskites and controlling their surface properties.The interaction between4-TBA and perovskite precursor materials was investigated using density functional theory(DFT)simulations.The electron-rich carbonyl group efficiently passivated the under-coordinated lead-ion defects.Additionally,hydrogen bonding between trifluoromethyl and organic cations prevents the generation of cation vacancies.Because of its intrinsic hydrophobicity,the trifluoromethyl group simultaneously improves the moisture and heat stability of the film.4-TBA serves as a universal modifier for various perovskite compositions.The power conversion efficiency(PCE)of inverted perovskite solar cells(PSCs)based on methylammonium(MA)with 4-TBA was improved from 16.15%to 19.28%.Similarly,the PCE of inverted PSCs based on a cesium formamidinium MA(CsFAMA)perovskite film increased from20.72%to 23.58%,upon addition of 4-TBA.Furthermore,the moisture and thermal stability of 4-TBAtreated films and devices was significantly enhanced,along with prolonged device performance.Our work provides guidance on selecting the structure and functional groups that are essential for surface defect passivation and the production of high-quality perovskites.展开更多
A comprehensive understanding of the relevance between molecular structure and passivation ability to screen efficient modifiers is essential for enhancing the performance of perovskite solar cells(PSCs).Here,three si...A comprehensive understanding of the relevance between molecular structure and passivation ability to screen efficient modifiers is essential for enhancing the performance of perovskite solar cells(PSCs).Here,three similarπ-πstacking molecules namely benzophenone(BPN),diphenyl sulfone(DPS),and diphenyl sulfoxide(DPSO)are used as back-interface modifiers in carbon-based CsPbBr_(3)PSCs.After investigation,the results demonstrate the positive effect of the p-πconjugation characteristic inπ-πstacking molecules on maximizing their passivation ability.The p-πco njugation of DPSO enables a higher coordinative activity of oxygen atom in its S=O group than that in 0=S=O group of DPS and C=O group of BPN,which gives a superior passivation effect of DPSO on defects of perovskite films.The modification of DPSO also significantly improves the p-type behavior of perovskite films and the back-interfacial energetics matching,inducing an increase of hole extraction and a decrease of energy loss.Finally,the unencapsulated carbon-based CsPbBr_(3)PSCs with DPSO achieve a maximum power conversion efficiency of 10.60%and outstanding long-term stability in high-temperature,high-humidity(85℃,85%relative humidity)air environment.This work provides insights into the influence of the structure ofπ-πstacking molecules on their ability to improve the perovskite films quality and therefore the PSCs performance.展开更多
Additive engineering has been widely employed to address defects-related issues in perovskite solar cells,including Pb^(2+)vacancy defects,halide migration,and FA^(+)lattice mismatch.However,due to the diversity and c...Additive engineering has been widely employed to address defects-related issues in perovskite solar cells,including Pb^(2+)vacancy defects,halide migration,and FA^(+)lattice mismatch.However,due to the diversity and complexity of defect types in perovskites,traditional monofunctional additives are typically limited to passivate specific types of defects and are unable to achieve effective passivation of multiple defects simultaneously.To overcome this limitation,this work proposes a multidentate synergistic coordination strategy using a multifunctional additive,ethyl 4-aminopyrazole-5-carboxylate(EAPC),to achieve coordinated passivation of multiple defects in perovskites.Combined theoretical calculations and experimental investigations reveal that the carbonyl group(C=O)of EAPC forms strong coordination bonds with uncoordinated Pb^(2+),while its amino group(–NH_(2))couples with halide ions,and the pyrazole-ring N sites establish a hydrogen-bonding network with FA^(+)cations,thereby achieving triple-site synergistic passivation of Pb^(2+)-X^(-)-FA^(+)defects.This synergistic effect accelerates the nucleation kinetics of perovskite while retarding its growth rate,thereby reducing the defect density and enhancing the crystallinity of the resulting perovskite films.Based on this strategy,the inverted perovskite solar cells(PSCs)achieved a champion power conversion efficiency(PCE)of 24.40%,maintaining over 90.2%of their initial efficiency after 1000 h of aging in a N_(2)-glovebox environment and retaining 85.1%of the original PCE under ambient conditions.This work pioneers a novel paradigm for synergistic defect passivation in perovskite optoelectronic devices.展开更多
Polycrystalline Si(poly-Si)-based passivating contacts are promising candidates for high-efficiency crystalline Si solar cells.We show that nanosecond-scale pulsed laser melting(PLM)is an industrially viable technique...Polycrystalline Si(poly-Si)-based passivating contacts are promising candidates for high-efficiency crystalline Si solar cells.We show that nanosecond-scale pulsed laser melting(PLM)is an industrially viable technique to fabricate such contacts with precisely controlled dopant concentration profiles that exceed the solid solubility limit.We demonstrate that conventionally doped,hole-selective poly-Si/SiO_(x)contacts that provide poor surface passivation of c-Si can be replaced with Ga-or B-doped contacts based on non-equilibrium doping.We overcome the solid solubility limit for both dopants in poly-Si by rapid cooling and recrystallization over a timescale of∼25 ns.We show an active Ga dopant concentration of∼3×10^(20)cm^(−3)in poly-Si which is six times higher than its solubility limit in c-Si,and a B dopant concentration as high as∼10^(21) cm^(−3).We measure an implied open-circuit voltage of 735 mV for Ga-doped poly-Si/SiO_(x)contacts on Czochralski Si with a low contact resistivity of 35.5±2.4 mΩcm^(2).Scanning spreading resistance microscopy and Kelvin probe force microscopy show large diffusion and drift current in the p-n junction that contributes to the low contact resistivity.Our results suggest that PLM can be extended for hyperdoping of other semiconductors with low solubility atoms to enable high-efficiency devices.展开更多
Clay minerals,phosphates,alkaline materials,organic materials are common improvers in the management of Cd polluted soil. This paper systematically summarized types of common soil improvers and their passivation mecha...Clay minerals,phosphates,alkaline materials,organic materials are common improvers in the management of Cd polluted soil. This paper systematically summarized types of common soil improvers and their passivation mechanism of Cd in soil. It reviewed advances in researches of soil improvers. Besides,it introduced major problems in four common passivating agents for management of Cd polluted soil. Finally,according to different mechanism characteristics of passivating agents,it came up with some recommendations.展开更多
Electrochemical jet machining(EJM)encounters significant challenges in the microstructuring of chemically inert and passivating materials because an oxide layer is easily formed on the material surface,preventing the ...Electrochemical jet machining(EJM)encounters significant challenges in the microstructuring of chemically inert and passivating materials because an oxide layer is easily formed on the material surface,preventing the progress of electrochemical dissolution.This research demonstrates for the first time a jet-electrolytic plasma micromachining(Jet-EPM)method to overcome this problem.Specifically,an electrolytic plasma is intentionally induced at the jet-material contact area by applying a potential high enough to surmount the surface boundary layer(such as a passive film or gas bubble)and enable material removal.Compared to traditional EJM,introducing plasma in the electrochemical jet system leads to considerable differences in machining performance due to the inclusion of plasma reactions.In this work,the implementation of Jet-EPM for fabricating microstructures in the semiconductor material 4H-SiC is demonstrated,and the machining principle and characteristics of Jet-EPM,including critical parameters and process windows,are comprehensively investigated.Theoretical modeling and experiments have elucidated the mechanisms of plasma ignition/evolution and the corresponding material removal,showing the strong potential of Jet-EPM for micromachining chemically resistant materials.The present study considerably augments the range of materials available for processing by the electrochemical jet technique.展开更多
Organic–inorganic halide perovskite(OIHP)solar cells have garnered great attention in the last decade since they continuously approach the Shockley–Queisser Limit.Compared with conventional organic and inorganic sem...Organic–inorganic halide perovskite(OIHP)solar cells have garnered great attention in the last decade since they continuously approach the Shockley–Queisser Limit.Compared with conventional organic and inorganic semiconductors,OIHPs possess the high tolerance on defects due to the dominated intrinsically shallow-level carrier-trapping centers.However,the existence of defects still causes the ion migration,produces the hysteresis effect,and accelerates the film degradation,eventually suppressing the device efficiency and stability.In this Review Article,we summarize recent impressive advance on passivating OIHP defects and discuss the future horizon of exploiting high-efficiency and long-stability OIHP solar cells in terms of defect managements.展开更多
Metal halide perovskite-based solar cells(PSCs) have rapidly-increased power conversion efficiency(PCE)exceeding 25% but poor stability especially under ultraviolet(UV) light. Meanwhile, non-radiative recombination ca...Metal halide perovskite-based solar cells(PSCs) have rapidly-increased power conversion efficiency(PCE)exceeding 25% but poor stability especially under ultraviolet(UV) light. Meanwhile, non-radiative recombination caused by diverse defects in perovskite absorbers and related interfaces is one of the major factors confining further development of PSCs. In this study, we systematically investigate the role of 2-(2-hydroxy-5-methylphenyl)benzotriazole(UVP) additive in perovskite layers. By adjusting the amount of doped UVP, the quality of perovskite absorbers is significantly improved with enlarged grains, longer lifetime and diffusion length of charge carriers. Furthermore, UVP not only reduces defects for less nonradiative recombination, but also matches energy level alignment for efficient interfacial charge extraction. X-ray photoelectron spectroscopy confirms that N-donor of UVP molecule coordinates with undercoordinated Pb^(2+) on the surface. Interestingly, UVP incorporated in PbI_(2) protects the perovskite by absorbing UV through the opening and closing of the chelating ring. Eventually, the UVP treated PSCs obtain a champion PCE of 22.46% with remarkably enhanced UV stability, retaining over 90% of initial PCE after 60 m W/cm^(2) strong UV irradiation for 9 h while the control maintaining only 74%. These results demonstrate a promising strategy fabricating passivated and UV-resistant perovskite materials simultaneously for efficient and stable perovskite photovoltaics.展开更多
Elements including P, Sb, Ce, La, B, Sn, Ti, Bi and Mg that could passivate Ni and V were studied on their migration on FCC catalysts and carriers under simulated commercial FCC operating conditions.Test results had s...Elements including P, Sb, Ce, La, B, Sn, Ti, Bi and Mg that could passivate Ni and V were studied on their migration on FCC catalysts and carriers under simulated commercial FCC operating conditions.Test results had shown that P, Sb, B and Sn compounds exhibited migration activity. The effects of temperature, fluidizing medium and contact time on migration of antimony compounds were investigated,and the mechanism regarding antimony migration was proposed. Meanwhile, it was disclosed that Ni on catalyst could stimulate Sb contained in the metal passivator to move onto FCC catalyst in tandem with the interaction between nickel and antimony.展开更多
With the in-depth implementation of sustainable development strategies,hydrogen energy as a clean energy source is receiving increasing attention[1,2].Among the various methods of hydrogen production,the electrocataly...With the in-depth implementation of sustainable development strategies,hydrogen energy as a clean energy source is receiving increasing attention[1,2].Among the various methods of hydrogen production,the electrocatalytic decomposition of abundant seawater into hydrogen utilizing renewable energy has emerged as a green and promising approach.However,natural seawater contains complex components,such as halide ions,which lead to the corrosion of catalysts or the occurrence of competitive side reactions during the electrolysis process[3].展开更多
In the aforementioned article,on page 5,the curves of current density and luminance with voltage variation for the device without and with ZnMy_(2)in figures 3(c)and(e)are incorrect.The voltage of the device without Z...In the aforementioned article,on page 5,the curves of current density and luminance with voltage variation for the device without and with ZnMy_(2)in figures 3(c)and(e)are incorrect.The voltage of the device without ZnMy_(2)should be 2.1 V not 2.2 V in the previous version.The larger current density should be around 18%,not 20%in the previous version.The luminance of the QLED based on ZnMy_(2)-treated QDs is improved by 50%compared to the device without ZnMy_(2)(116944 cd m^(−2)),not 67%and 105127 cd m^(−2)in the previous version.The the maximum EQE and current efficiency for the QLEDs without ZnMy_(2)are 9.19%and 36.90 cd A^(−1),respectively,not 9.22%and 36.72 cd A^(−1)in the previous version.Corrected version of figures 3(c)and(e)are shown below.展开更多
Ultra-thin single crystal film(SCF)without grain boundary inherits low charge recombination probability as bulk single crystals.However,its low depth brings a high surface defect ratio and hinders the carrier transpor...Ultra-thin single crystal film(SCF)without grain boundary inherits low charge recombination probability as bulk single crystals.However,its low depth brings a high surface defect ratio and hinders the carrier transport and extraction,which affects the performance and stability of optoelectronic devices such as photodetectors,and thus surface defect passivation is of great practical significance.In this paper,we use the space confined method to grow MAPbBr_(3) SCF and selected BA_(2)PbI_(4) for surface defect passivation.The results reveal that BA cation passivates MA vacancy surface defects,reduces carrier recombination,and enhances carrier lifetime.The carrier mobility is as high as 33.6 cm^(2) V^(-1)s^(-1),and the surface defect density is reduced to 3.4×10^(12)cm^(-3).Therefore,the self-driven vertical MAPbBr_(3) SCF photodetector after surface passivation exhibits more excellent optoelectronic performance.展开更多
The introduction of two-dimensional(2D)perovskite layers on top of three-dimensional(3D)perovskite films enhances the performance and stability of perovskite solar cells(PSCs).However,the electronic effect of the spac...The introduction of two-dimensional(2D)perovskite layers on top of three-dimensional(3D)perovskite films enhances the performance and stability of perovskite solar cells(PSCs).However,the electronic effect of the spacer cation and the quality of the 2D capping layer are critical factors in achieving the required results.In this study,we compared two fluorinated salts:4-(trifluoromethyl)benzamidine hydrochloride(4TF-BA·HCl)and 4-fluorobenzamidine hydrochloride(4F-BA·HCl)to engineer the 3D/2D perovskite films.Surprisingly,4F-BA formed a high-performance 3D/2D heterojunction,while4TF-BA produced an amorphous layer on the perovskite films.Our findings indicate that the balanced intramolecular charge polarization,which leads to effective hydrogen bonding,is more favorable in 4F-BA than in 4TF-BA,promoting the formation of a crystalline 2D perovskite.Nevertheless,4TF-BA managed to improve efficiency to 24%,surpassing the control device,primarily due to the natural passivation capabilities of benzamidine.Interestingly,the devices based on 4F-BA demonstrated an efficiency exceeding 25%with greater longevity under various storage conditions compared to 4TF-BA-based and the control devices.展开更多
Perovskite solar cells(PSCs)have emerged as promising photovoltaic technologies owing to their remarkable power conversion efficiency(PCE).However,heat accumulation under continuous illumination remains a critical bot...Perovskite solar cells(PSCs)have emerged as promising photovoltaic technologies owing to their remarkable power conversion efficiency(PCE).However,heat accumulation under continuous illumination remains a critical bottleneck,severely affecting device stability and long-term operational performance.Herein,we present a multifunctional strategy by incorporating highly thermally conductive Ti_(3)C_(2)T_(X) MXene nanosheets into the perovskite layer to simultaneously enhance thermal management and optoelectronic properties.The Ti_(3)C_(2)T_(X) nanosheets,embedded at perovskite grain boundaries,construct efficient thermal conduction pathways,significantly improving the thermal conductivity and diffusivity of the film.This leads to a notable reduction in the device’s steady-state operating temperature from 42.96 to 39.97 under 100 mW cm^(−2) illumination,thereby alleviating heat-induced performance degradation.Beyond thermal regulation,Ti_(3)C_(2)T_(X),with high conductivity and negatively charged surface terminations,also serves as an effective defect passivation agent,reducing trap-assisted recombination,while simultaneously facilitating charge extraction and transport by optimizing interfacial energy alignment.As a result,the Ti_(3)C_(2)T_(X)-modified PSC achieve a champion PCE of 25.13%and exhibit outstanding thermal stability,retaining 80%of the initial PCE after 500 h of thermal aging at 85 and 30±5%relative humidity.(In contrast,control PSC retain only 58%after 200 h.)Moreover,under continuous maximum power point tracking in N2 atmosphere,Ti_(3)C_(2)T_(X)-modified PSC retained 70%of the initial PCE after 500 h,whereas the control PSC drop sharply to 20%.These findings highlight the synergistic role of Ti_(3)C_(2)T_(X) in thermal management and optoelectronic performance,paving the way for the development of high-efficiency and heat-resistant perovskite photovoltaics.展开更多
During electrochemical machining(ECM),the passivation film formed on the surface of titanium alloy can lead to uneven dissolution and pitting.Solid particle erosion can effectively remove this passivation film.In this...During electrochemical machining(ECM),the passivation film formed on the surface of titanium alloy can lead to uneven dissolution and pitting.Solid particle erosion can effectively remove this passivation film.In this paper,the electrochemical dissolution behavior of Ti-6.5Al-2Zr-1Mo-1V(TA15)titanium alloy at without particle impact,low(15°)and high(90°)angle particle impact was investigated,and the influence of Al_(2)O_(3)particles on ECM was systematically expounded.It was found that under the condition of no particle erosion,the surface of electrochemically processed titanium alloy had serious pitting corrosion due to the influence of the passivation film,and the surface roughness(Sa)of the local area reached 10.088μm.Under the condition of a high-impact angle(90°),due to the existence of strain hardening and particle embedding,only the edge of the surface is dissolved,while the central area is almost insoluble,with the surface roughness(S_(a))reaching 16.086μm.On the contrary,under the condition of a low-impact angle(15°),the machining efficiency and surface quality of the material were significantly improved due to the ploughing effect and galvanic corrosion,and the surface roughness(S_(a))reached 2.823μm.Based on these findings,the electrochemical dissolution model of TA15 titanium alloy under different particle erosion conditions was established.展开更多
Molten salt reactors,being the only reactor type among Generation Ⅳ advanced nuclear reactors that utilize liquid fuels,offer inherent safety,high-temperature,and low-pressure operation,as well as the capability for ...Molten salt reactors,being the only reactor type among Generation Ⅳ advanced nuclear reactors that utilize liquid fuels,offer inherent safety,high-temperature,and low-pressure operation,as well as the capability for online fuel reprocessing.However,the fuel-salt flow results in the decay of delayed neutron precursors(DNPs)outside the core,causing fluctuations in the effective delayed neutron fraction and consequently impacting the reactor reactivity.Particularly in accident scenarios—such as a combined pump shutdown and the inability to rapidly scram the reactor—the sole reliance on negative temperature feedback may cause a significant increase in core temperature,posing a threat to reactor safety.To address these problems,this paper introduces an innovative design for a passive fluid-driven suspended control rod(SCR)to dynamically compensate for reactivity fluctuations caused by DNPs flowing with the fuel.The control rod operates passively by leveraging the combined effects of gravity,buoyancy,and fluid dynamic forces,thereby eliminating the need for an external drive mechanism and enabling direct integration within the active region of the core.Using a 150 MWt thorium-based molten salt reactor as the reference design,we develop a mathematical model to systematically analyze the effects of key parameters—including the geometric dimensions and density of the SCR—on its performance.We examine its motion characteristics under different core flow conditions and assess its feasibility for the dynamic compensation of reactivity changes caused by fuel flow.The results of this study demonstrate that the SCR can effectively counteract reactivity fluctuations induced by fuel flow within molten salt reactors.A sensitivity analysis reveals that the SCR’s average density exerts a profound impact on its start-up flow threshold,channel flow rate,resistance to fuel density fluctuations,and response characteristics.This underscores the critical need to optimize this parameter.Moreover,by judiciously selecting the SCR’s length,number of deployed units,and the placement we can achieve the necessary reactivity control while maintaining a favorable balance between neutron economy and heat transfer performance.Ultimately,this paper provides an innovative solution for the passive reactivity control in molten salt reactors,offering significant potential for practical engineering applications.展开更多
Tandem solar cells are a key technology for exceeding the theoretical efficiency limit of single-junction cells.One of the most promising combinations is the silicon–perovskite tandem cells,considering their potentia...Tandem solar cells are a key technology for exceeding the theoretical efficiency limit of single-junction cells.One of the most promising combinations is the silicon–perovskite tandem cells,considering their potential for high efficiency,fabrication on a large scale,and low cost.While most research focuses on improving each subcell,another key challenge lies in the tunnel junction that connects these subcells,significantly impacting the overall cell characteristics.Here,we demonstrate the first use of tunnel junctions using a stack of p+/n+polysilicon passivating contacts deposited directly on the tunnel oxide to overcome the drawbacks of conventional metal oxide-based tunnel junctions,including low tunneling efficiency and sputter damage.Using Random Forest analysis,we achieved high implied open circuit voltages over 700 mV and low contact resistivities of 500 mΩcm 2,suggesting fill factor losses of less than 1%abs for the operating conditions of a tandem cell.展开更多
Many organic molecules with various functional groups have been used to passivate the perovskite surface for improving the efficiency and stability of perovskite solar cell(PSCs).However,the intrinsic attributes of th...Many organic molecules with various functional groups have been used to passivate the perovskite surface for improving the efficiency and stability of perovskite solar cell(PSCs).However,the intrinsic attributes of the passivation effect based on different chemical bonds are rarely studied.Here,we comparatively investigate the passivation effect among 12 types of functional groups on para-tertbutylbenzene for PSCs and find that the open circuit voltage(VOC) tends to increase with the chemical bonding strength between perovskite and these passivation additive molecules.Particularly,the paratert-butylbenzoic acid(tB-COOH),with the extra intermolecular hydrogen bonding,can stabilize the surface passivation of perovskite films exceptionally well through formation of a crystalline interlayer with water-insoluble property and high melting point.As a result,the tB-COOH device achieves a champion power conversion efficiency(PCE) of 21.46%.More importantly,such devices,which were stored in ambient air with a relative humidity of ~45%,can retain 88% of their initial performance after a testing period of more than 1 year(10,080 h).This work provides a case study to understand chemical bonding effects on passivation of perovskite.展开更多
The precisely customizable attributes of self-assembled monolayers(SAMs)molecules at the atomic level hold the potential to facilitate efficient hole selection and interface passivation simultaneously.However,the corr...The precisely customizable attributes of self-assembled monolayers(SAMs)molecules at the atomic level hold the potential to facilitate efficient hole selection and interface passivation simultaneously.However,the correlation between the exposure of passivating groups on the surface and device performance remains unexplored.Herein,we introduce two newly designed SAM molecules,Cbz2S and Cbz2SMe,incorporating cyclic disulfide or two flanking thiomethyls by modifying the 4,5-position of carbazole to adjust the Lewis basicity of the SAM-modified surface.Despite possessing suitable energetic alignment,Cbz2S with more-exposed sulfur atoms exhibited inferior device performance due to excessive reactivity,leading to an overpopulation of PbI2 crystallites at the buried perovskite interface.In contrast,the screening effect from the methyl groups of Cbz2SMe optimized SAM reactivity,exquisitely integrating buried interface passivation and hole selection together.Consequently,the champion inverted perovskite solar cell(PSC)employing Cbz2SMe achieved an impressive power conversion efficiency of 24.42%,accompanied by prolonged stability.This work demonstrates the feasibility of incorporating Lewis-basic passivation groups into SAM molecules and elucidates the relationship between the reactivity of SAM passivation groups and device performance.These findings provide valuable insights for the design of novel multifunctional SAM molecules,further advancing the performance of PSCs.展开更多
The performance of red InP and blue ZnTeSe-based quantum dots(QDs)and corresponding QD light emitting diodes(QLEDs)has already been improved significantly,whose external quantum efficiencies(EQEs)and luminances have e...The performance of red InP and blue ZnTeSe-based quantum dots(QDs)and corresponding QD light emitting diodes(QLEDs)has already been improved significantly,whose external quantum efficiencies(EQEs)and luminances have exceeded 20%and 80000 cd m-2,respectively.However,the inferior performance of the green InP-based device hinders the commercialization of full-color Cd-free QLED technology.The ease of oxidation of the highly reactive InP cores leads to high non-radiative recombination and poor photoluminescence quantum yield(PL QY)of the InP-based core/shell QDs,limiting the performance of the relevant QLEDs.Here,we proposed a fluoride-free synthesis strategy to in-situ passivate the InP cores,in which zinc myristate reacted with phosphine dangling bonds to form Zn–P protective layer and protect InP cores from the water and oxygen in the environment.The resultant InP/ZnSe/ZnS core/shell QDs demonstrated a high PL QY of 91%.The corresponding green-emitting electroluminescence devices exhibited a maximum EQE of 12.74%,along with a luminance of over 175000 cd m^(-2)and a long T50@100 cd m^(-2)lifetime of over 20000 h.展开更多
基金supported by a Research Grant of Pukyong National University(2023)。
文摘Achieving high-quality perovskite films without surface defects is regarded as a crucial target for the development of durable high-performance perovskite solar cells.Additive engineering is commonly employed to simultaneously control the growth of perovskite crystals and passivate defects.Here,4-(trifluoromethyl)benzoic anhydride(4-TBA)composed of benzene rings functionalized with carbonyl and trifluoromethyl groups was used as an example additive to study the characteristics of additives used for producing high-quality perovskites and controlling their surface properties.The interaction between4-TBA and perovskite precursor materials was investigated using density functional theory(DFT)simulations.The electron-rich carbonyl group efficiently passivated the under-coordinated lead-ion defects.Additionally,hydrogen bonding between trifluoromethyl and organic cations prevents the generation of cation vacancies.Because of its intrinsic hydrophobicity,the trifluoromethyl group simultaneously improves the moisture and heat stability of the film.4-TBA serves as a universal modifier for various perovskite compositions.The power conversion efficiency(PCE)of inverted perovskite solar cells(PSCs)based on methylammonium(MA)with 4-TBA was improved from 16.15%to 19.28%.Similarly,the PCE of inverted PSCs based on a cesium formamidinium MA(CsFAMA)perovskite film increased from20.72%to 23.58%,upon addition of 4-TBA.Furthermore,the moisture and thermal stability of 4-TBAtreated films and devices was significantly enhanced,along with prolonged device performance.Our work provides guidance on selecting the structure and functional groups that are essential for surface defect passivation and the production of high-quality perovskites.
基金financial supports from the Natural Science Foundation of Shandong Province(ZR2021ME037)the National Natural Science Foundation of China(52472259,22179051 and 61604143)+2 种基金the National Key Research and Development Program of China(2021YFE0111000)the Special Fund of Taishan Scholar Program of Shandong Province(tsqnz20221141)the Foundation of Key Laboratory of Advanced Technique&Preparation for Renewable Energy Materials,Ministry of Education,Yunnan Normal University(OF2022-02)。
文摘A comprehensive understanding of the relevance between molecular structure and passivation ability to screen efficient modifiers is essential for enhancing the performance of perovskite solar cells(PSCs).Here,three similarπ-πstacking molecules namely benzophenone(BPN),diphenyl sulfone(DPS),and diphenyl sulfoxide(DPSO)are used as back-interface modifiers in carbon-based CsPbBr_(3)PSCs.After investigation,the results demonstrate the positive effect of the p-πconjugation characteristic inπ-πstacking molecules on maximizing their passivation ability.The p-πco njugation of DPSO enables a higher coordinative activity of oxygen atom in its S=O group than that in 0=S=O group of DPS and C=O group of BPN,which gives a superior passivation effect of DPSO on defects of perovskite films.The modification of DPSO also significantly improves the p-type behavior of perovskite films and the back-interfacial energetics matching,inducing an increase of hole extraction and a decrease of energy loss.Finally,the unencapsulated carbon-based CsPbBr_(3)PSCs with DPSO achieve a maximum power conversion efficiency of 10.60%and outstanding long-term stability in high-temperature,high-humidity(85℃,85%relative humidity)air environment.This work provides insights into the influence of the structure ofπ-πstacking molecules on their ability to improve the perovskite films quality and therefore the PSCs performance.
基金financially supported by the Changzhou Shichuang Energy Co.Ltd of China(Grant no.K81B2038)the National Natural Science Foundation of China(Grant no.50902116)。
文摘Additive engineering has been widely employed to address defects-related issues in perovskite solar cells,including Pb^(2+)vacancy defects,halide migration,and FA^(+)lattice mismatch.However,due to the diversity and complexity of defect types in perovskites,traditional monofunctional additives are typically limited to passivate specific types of defects and are unable to achieve effective passivation of multiple defects simultaneously.To overcome this limitation,this work proposes a multidentate synergistic coordination strategy using a multifunctional additive,ethyl 4-aminopyrazole-5-carboxylate(EAPC),to achieve coordinated passivation of multiple defects in perovskites.Combined theoretical calculations and experimental investigations reveal that the carbonyl group(C=O)of EAPC forms strong coordination bonds with uncoordinated Pb^(2+),while its amino group(–NH_(2))couples with halide ions,and the pyrazole-ring N sites establish a hydrogen-bonding network with FA^(+)cations,thereby achieving triple-site synergistic passivation of Pb^(2+)-X^(-)-FA^(+)defects.This synergistic effect accelerates the nucleation kinetics of perovskite while retarding its growth rate,thereby reducing the defect density and enhancing the crystallinity of the resulting perovskite films.Based on this strategy,the inverted perovskite solar cells(PSCs)achieved a champion power conversion efficiency(PCE)of 24.40%,maintaining over 90.2%of their initial efficiency after 1000 h of aging in a N_(2)-glovebox environment and retaining 85.1%of the original PCE under ambient conditions.This work pioneers a novel paradigm for synergistic defect passivation in perovskite optoelectronic devices.
基金the National Renewable Energy Laboratory,operated by Alliance for Sustainable Energy,LLC,for the U.S.Department of Energy(DOE)under Contract No.DE-AC36-08GO28308.
文摘Polycrystalline Si(poly-Si)-based passivating contacts are promising candidates for high-efficiency crystalline Si solar cells.We show that nanosecond-scale pulsed laser melting(PLM)is an industrially viable technique to fabricate such contacts with precisely controlled dopant concentration profiles that exceed the solid solubility limit.We demonstrate that conventionally doped,hole-selective poly-Si/SiO_(x)contacts that provide poor surface passivation of c-Si can be replaced with Ga-or B-doped contacts based on non-equilibrium doping.We overcome the solid solubility limit for both dopants in poly-Si by rapid cooling and recrystallization over a timescale of∼25 ns.We show an active Ga dopant concentration of∼3×10^(20)cm^(−3)in poly-Si which is six times higher than its solubility limit in c-Si,and a B dopant concentration as high as∼10^(21) cm^(−3).We measure an implied open-circuit voltage of 735 mV for Ga-doped poly-Si/SiO_(x)contacts on Czochralski Si with a low contact resistivity of 35.5±2.4 mΩcm^(2).Scanning spreading resistance microscopy and Kelvin probe force microscopy show large diffusion and drift current in the p-n junction that contributes to the low contact resistivity.Our results suggest that PLM can be extended for hyperdoping of other semiconductors with low solubility atoms to enable high-efficiency devices.
基金Supported by National Key Research and Development Program(2016YED0800705-01)Key Research and Development Program of Guangxi(Gui Ke AB16380084)+2 种基金Key Agricultural Science and Technology Program of Guangxi(201528,201604)Scientific Research and Technological Development Program Project of Nanning City(20162105)Scientific Development Fund Project of Guangxi Academy of Agricultural Sciences(Gui Nong Ke2017JM06,2017JM07)
文摘Clay minerals,phosphates,alkaline materials,organic materials are common improvers in the management of Cd polluted soil. This paper systematically summarized types of common soil improvers and their passivation mechanism of Cd in soil. It reviewed advances in researches of soil improvers. Besides,it introduced major problems in four common passivating agents for management of Cd polluted soil. Finally,according to different mechanism characteristics of passivating agents,it came up with some recommendations.
基金supported by the National Key R&D Pro-gram of China(No.2021YFF0501700)the National Nat-ural Science Foundation of China(No.51905255)+1 种基金the Project of Guangdong Provincial Department of Education(No.2019KTSCX152)the Shenzhen Science and Technology Pro-gram(No.GJHZ20200731095204014).
文摘Electrochemical jet machining(EJM)encounters significant challenges in the microstructuring of chemically inert and passivating materials because an oxide layer is easily formed on the material surface,preventing the progress of electrochemical dissolution.This research demonstrates for the first time a jet-electrolytic plasma micromachining(Jet-EPM)method to overcome this problem.Specifically,an electrolytic plasma is intentionally induced at the jet-material contact area by applying a potential high enough to surmount the surface boundary layer(such as a passive film or gas bubble)and enable material removal.Compared to traditional EJM,introducing plasma in the electrochemical jet system leads to considerable differences in machining performance due to the inclusion of plasma reactions.In this work,the implementation of Jet-EPM for fabricating microstructures in the semiconductor material 4H-SiC is demonstrated,and the machining principle and characteristics of Jet-EPM,including critical parameters and process windows,are comprehensively investigated.Theoretical modeling and experiments have elucidated the mechanisms of plasma ignition/evolution and the corresponding material removal,showing the strong potential of Jet-EPM for micromachining chemically resistant materials.The present study considerably augments the range of materials available for processing by the electrochemical jet technique.
文摘Organic–inorganic halide perovskite(OIHP)solar cells have garnered great attention in the last decade since they continuously approach the Shockley–Queisser Limit.Compared with conventional organic and inorganic semiconductors,OIHPs possess the high tolerance on defects due to the dominated intrinsically shallow-level carrier-trapping centers.However,the existence of defects still causes the ion migration,produces the hysteresis effect,and accelerates the film degradation,eventually suppressing the device efficiency and stability.In this Review Article,we summarize recent impressive advance on passivating OIHP defects and discuss the future horizon of exploiting high-efficiency and long-stability OIHP solar cells in terms of defect managements.
基金financially supported by the National Key R&D Program of China(2018YFB1500105)the Natural Science Foundation of China(61874167)+3 种基金the Fundamental Research Funds for Central Universitiesthe 111 Project(B16027)the International Cooperation Base(2016D01025)the National Natural Science Foundation of China(51773045,21772030,51922032,21961160720)for financial support。
文摘Metal halide perovskite-based solar cells(PSCs) have rapidly-increased power conversion efficiency(PCE)exceeding 25% but poor stability especially under ultraviolet(UV) light. Meanwhile, non-radiative recombination caused by diverse defects in perovskite absorbers and related interfaces is one of the major factors confining further development of PSCs. In this study, we systematically investigate the role of 2-(2-hydroxy-5-methylphenyl)benzotriazole(UVP) additive in perovskite layers. By adjusting the amount of doped UVP, the quality of perovskite absorbers is significantly improved with enlarged grains, longer lifetime and diffusion length of charge carriers. Furthermore, UVP not only reduces defects for less nonradiative recombination, but also matches energy level alignment for efficient interfacial charge extraction. X-ray photoelectron spectroscopy confirms that N-donor of UVP molecule coordinates with undercoordinated Pb^(2+) on the surface. Interestingly, UVP incorporated in PbI_(2) protects the perovskite by absorbing UV through the opening and closing of the chelating ring. Eventually, the UVP treated PSCs obtain a champion PCE of 22.46% with remarkably enhanced UV stability, retaining over 90% of initial PCE after 60 m W/cm^(2) strong UV irradiation for 9 h while the control maintaining only 74%. These results demonstrate a promising strategy fabricating passivated and UV-resistant perovskite materials simultaneously for efficient and stable perovskite photovoltaics.
文摘Elements including P, Sb, Ce, La, B, Sn, Ti, Bi and Mg that could passivate Ni and V were studied on their migration on FCC catalysts and carriers under simulated commercial FCC operating conditions.Test results had shown that P, Sb, B and Sn compounds exhibited migration activity. The effects of temperature, fluidizing medium and contact time on migration of antimony compounds were investigated,and the mechanism regarding antimony migration was proposed. Meanwhile, it was disclosed that Ni on catalyst could stimulate Sb contained in the metal passivator to move onto FCC catalyst in tandem with the interaction between nickel and antimony.
基金financially supported by the Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications(No.NY223016)Qinglan Project of Jiangsu Province of China2024 Nanjing Science and Technology Innovation Program(No.NJKCZYZZ2024-06)。
文摘With the in-depth implementation of sustainable development strategies,hydrogen energy as a clean energy source is receiving increasing attention[1,2].Among the various methods of hydrogen production,the electrocatalytic decomposition of abundant seawater into hydrogen utilizing renewable energy has emerged as a green and promising approach.However,natural seawater contains complex components,such as halide ions,which lead to the corrosion of catalysts or the occurrence of competitive side reactions during the electrolysis process[3].
文摘In the aforementioned article,on page 5,the curves of current density and luminance with voltage variation for the device without and with ZnMy_(2)in figures 3(c)and(e)are incorrect.The voltage of the device without ZnMy_(2)should be 2.1 V not 2.2 V in the previous version.The larger current density should be around 18%,not 20%in the previous version.The luminance of the QLED based on ZnMy_(2)-treated QDs is improved by 50%compared to the device without ZnMy_(2)(116944 cd m^(−2)),not 67%and 105127 cd m^(−2)in the previous version.The the maximum EQE and current efficiency for the QLEDs without ZnMy_(2)are 9.19%and 36.90 cd A^(−1),respectively,not 9.22%and 36.72 cd A^(−1)in the previous version.Corrected version of figures 3(c)and(e)are shown below.
基金supported by the National Natural Science Foundation of China(No.52072225)Shandong Province Key Research and Development Plan(No.2024SFGC0102).
文摘Ultra-thin single crystal film(SCF)without grain boundary inherits low charge recombination probability as bulk single crystals.However,its low depth brings a high surface defect ratio and hinders the carrier transport and extraction,which affects the performance and stability of optoelectronic devices such as photodetectors,and thus surface defect passivation is of great practical significance.In this paper,we use the space confined method to grow MAPbBr_(3) SCF and selected BA_(2)PbI_(4) for surface defect passivation.The results reveal that BA cation passivates MA vacancy surface defects,reduces carrier recombination,and enhances carrier lifetime.The carrier mobility is as high as 33.6 cm^(2) V^(-1)s^(-1),and the surface defect density is reduced to 3.4×10^(12)cm^(-3).Therefore,the self-driven vertical MAPbBr_(3) SCF photodetector after surface passivation exhibits more excellent optoelectronic performance.
基金supported by the National Key Research and Development Programs-Intergovernmental International Cooperation in Science and Technology Innovation Project(Grant No.2022YFE0118400)the Natural Science Foundation of Hunan Province(2023JJ50132)+1 种基金Shenzhen Science and Technology Innovation Committee(Grants Nos.JCYJ20220818100211025,and KCXST20221021111616039)Shenzhen Science and Technology Program(No.20231128110928003)。
文摘The introduction of two-dimensional(2D)perovskite layers on top of three-dimensional(3D)perovskite films enhances the performance and stability of perovskite solar cells(PSCs).However,the electronic effect of the spacer cation and the quality of the 2D capping layer are critical factors in achieving the required results.In this study,we compared two fluorinated salts:4-(trifluoromethyl)benzamidine hydrochloride(4TF-BA·HCl)and 4-fluorobenzamidine hydrochloride(4F-BA·HCl)to engineer the 3D/2D perovskite films.Surprisingly,4F-BA formed a high-performance 3D/2D heterojunction,while4TF-BA produced an amorphous layer on the perovskite films.Our findings indicate that the balanced intramolecular charge polarization,which leads to effective hydrogen bonding,is more favorable in 4F-BA than in 4TF-BA,promoting the formation of a crystalline 2D perovskite.Nevertheless,4TF-BA managed to improve efficiency to 24%,surpassing the control device,primarily due to the natural passivation capabilities of benzamidine.Interestingly,the devices based on 4F-BA demonstrated an efficiency exceeding 25%with greater longevity under various storage conditions compared to 4TF-BA-based and the control devices.
基金the National Natural Science Foundation of China(Nos.62374029,22175029,62474033,and W2433038)the Young Elite Scientists Sponsorship Program by CAST(No.YESS20220550)+2 种基金the Sichuan Science and Technology Program(No.2024NSFSC0250)the Natural Science Foundation of Shenzhen Innovation Committee(JCYJ20210324135614040)the Fundamental Research Funds for the Central Universities of China(No.ZYGX2022J032).
文摘Perovskite solar cells(PSCs)have emerged as promising photovoltaic technologies owing to their remarkable power conversion efficiency(PCE).However,heat accumulation under continuous illumination remains a critical bottleneck,severely affecting device stability and long-term operational performance.Herein,we present a multifunctional strategy by incorporating highly thermally conductive Ti_(3)C_(2)T_(X) MXene nanosheets into the perovskite layer to simultaneously enhance thermal management and optoelectronic properties.The Ti_(3)C_(2)T_(X) nanosheets,embedded at perovskite grain boundaries,construct efficient thermal conduction pathways,significantly improving the thermal conductivity and diffusivity of the film.This leads to a notable reduction in the device’s steady-state operating temperature from 42.96 to 39.97 under 100 mW cm^(−2) illumination,thereby alleviating heat-induced performance degradation.Beyond thermal regulation,Ti_(3)C_(2)T_(X),with high conductivity and negatively charged surface terminations,also serves as an effective defect passivation agent,reducing trap-assisted recombination,while simultaneously facilitating charge extraction and transport by optimizing interfacial energy alignment.As a result,the Ti_(3)C_(2)T_(X)-modified PSC achieve a champion PCE of 25.13%and exhibit outstanding thermal stability,retaining 80%of the initial PCE after 500 h of thermal aging at 85 and 30±5%relative humidity.(In contrast,control PSC retain only 58%after 200 h.)Moreover,under continuous maximum power point tracking in N2 atmosphere,Ti_(3)C_(2)T_(X)-modified PSC retained 70%of the initial PCE after 500 h,whereas the control PSC drop sharply to 20%.These findings highlight the synergistic role of Ti_(3)C_(2)T_(X) in thermal management and optoelectronic performance,paving the way for the development of high-efficiency and heat-resistant perovskite photovoltaics.
基金supported by the National Natural Science Foundation of China(No.52175414)the Natural Science Foundation of Jiangsu Province of China(No.BK20220134)+1 种基金the Fundamental Research Funds for the Central Universities,China(No.NE2023002)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(No.KYCX24_0559)。
文摘During electrochemical machining(ECM),the passivation film formed on the surface of titanium alloy can lead to uneven dissolution and pitting.Solid particle erosion can effectively remove this passivation film.In this paper,the electrochemical dissolution behavior of Ti-6.5Al-2Zr-1Mo-1V(TA15)titanium alloy at without particle impact,low(15°)and high(90°)angle particle impact was investigated,and the influence of Al_(2)O_(3)particles on ECM was systematically expounded.It was found that under the condition of no particle erosion,the surface of electrochemically processed titanium alloy had serious pitting corrosion due to the influence of the passivation film,and the surface roughness(Sa)of the local area reached 10.088μm.Under the condition of a high-impact angle(90°),due to the existence of strain hardening and particle embedding,only the edge of the surface is dissolved,while the central area is almost insoluble,with the surface roughness(S_(a))reaching 16.086μm.On the contrary,under the condition of a low-impact angle(15°),the machining efficiency and surface quality of the material were significantly improved due to the ploughing effect and galvanic corrosion,and the surface roughness(S_(a))reached 2.823μm.Based on these findings,the electrochemical dissolution model of TA15 titanium alloy under different particle erosion conditions was established.
基金supported by Youth Innovation Promotion Association of Chinese Academy of Sciences(No.2020261)Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA02010000)the Young Potential Program of Shanghai Institute of Applied Physics,Chinese Academy of Sciences(No.SINAP-YXJH-202412).
文摘Molten salt reactors,being the only reactor type among Generation Ⅳ advanced nuclear reactors that utilize liquid fuels,offer inherent safety,high-temperature,and low-pressure operation,as well as the capability for online fuel reprocessing.However,the fuel-salt flow results in the decay of delayed neutron precursors(DNPs)outside the core,causing fluctuations in the effective delayed neutron fraction and consequently impacting the reactor reactivity.Particularly in accident scenarios—such as a combined pump shutdown and the inability to rapidly scram the reactor—the sole reliance on negative temperature feedback may cause a significant increase in core temperature,posing a threat to reactor safety.To address these problems,this paper introduces an innovative design for a passive fluid-driven suspended control rod(SCR)to dynamically compensate for reactivity fluctuations caused by DNPs flowing with the fuel.The control rod operates passively by leveraging the combined effects of gravity,buoyancy,and fluid dynamic forces,thereby eliminating the need for an external drive mechanism and enabling direct integration within the active region of the core.Using a 150 MWt thorium-based molten salt reactor as the reference design,we develop a mathematical model to systematically analyze the effects of key parameters—including the geometric dimensions and density of the SCR—on its performance.We examine its motion characteristics under different core flow conditions and assess its feasibility for the dynamic compensation of reactivity changes caused by fuel flow.The results of this study demonstrate that the SCR can effectively counteract reactivity fluctuations induced by fuel flow within molten salt reactors.A sensitivity analysis reveals that the SCR’s average density exerts a profound impact on its start-up flow threshold,channel flow rate,resistance to fuel density fluctuations,and response characteristics.This underscores the critical need to optimize this parameter.Moreover,by judiciously selecting the SCR’s length,number of deployed units,and the placement we can achieve the necessary reactivity control while maintaining a favorable balance between neutron economy and heat transfer performance.Ultimately,this paper provides an innovative solution for the passive reactivity control in molten salt reactors,offering significant potential for practical engineering applications.
基金This research was funded by the New&Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Eval-uation and Planning(KETEP),and supported by the ministry of Trade,Industry,Energy,of the Republic of Korea(No.20204010600470)Munho Kim acknowledges the support of Ministry of Education,Sin-gapore,under AcRF Tier 2(T2EP50120-0001)。
文摘Tandem solar cells are a key technology for exceeding the theoretical efficiency limit of single-junction cells.One of the most promising combinations is the silicon–perovskite tandem cells,considering their potential for high efficiency,fabrication on a large scale,and low cost.While most research focuses on improving each subcell,another key challenge lies in the tunnel junction that connects these subcells,significantly impacting the overall cell characteristics.Here,we demonstrate the first use of tunnel junctions using a stack of p+/n+polysilicon passivating contacts deposited directly on the tunnel oxide to overcome the drawbacks of conventional metal oxide-based tunnel junctions,including low tunneling efficiency and sputter damage.Using Random Forest analysis,we achieved high implied open circuit voltages over 700 mV and low contact resistivities of 500 mΩcm 2,suggesting fill factor losses of less than 1%abs for the operating conditions of a tandem cell.
基金supported by the Research Grants Council of Hong Kong (T23-407/13-N)Innovation and Technology Commission (ITS/088/17)+5 种基金Start-up funds from Central Organization Department and South China University of Technologyfund from the Guangdong Science and Technology Program (2020B121201003)the National Natural Science Foundation of China (21776315)Petro China Innovation Foundation (2017D5007-0402)the Pearl River Talent Program (2019ZT08L075, 2019QN01L118)Fundamental Research Funds for the Central Universities (19CX05001A)。
文摘Many organic molecules with various functional groups have been used to passivate the perovskite surface for improving the efficiency and stability of perovskite solar cell(PSCs).However,the intrinsic attributes of the passivation effect based on different chemical bonds are rarely studied.Here,we comparatively investigate the passivation effect among 12 types of functional groups on para-tertbutylbenzene for PSCs and find that the open circuit voltage(VOC) tends to increase with the chemical bonding strength between perovskite and these passivation additive molecules.Particularly,the paratert-butylbenzoic acid(tB-COOH),with the extra intermolecular hydrogen bonding,can stabilize the surface passivation of perovskite films exceptionally well through formation of a crystalline interlayer with water-insoluble property and high melting point.As a result,the tB-COOH device achieves a champion power conversion efficiency(PCE) of 21.46%.More importantly,such devices,which were stored in ambient air with a relative humidity of ~45%,can retain 88% of their initial performance after a testing period of more than 1 year(10,080 h).This work provides a case study to understand chemical bonding effects on passivation of perovskite.
基金support from the CityU Infrastructure Support from Central (APRCgrant nos.9380086,9610419,9610492,and 9610508)of the City University of Hong Kong+5 种基金the Guangdong-Hong Kong Technology Cooperation Funding Scheme (TCFS,grant no.GHP/018/20SZ)Midstream Research Programme for Universities (MRP)Grant (grant no.MRP/040/21X)from the Innovation and Technology Commission of Hong Kongthe Green Tech Fund (grant no.202020164)from the Environment and Ecology Bureau of Hong Kongthe General Research Fund (GRF,grant nos.11307621 and 11316422)from the Research Grants Council of Hong KongShenzhen Science and Technology Program (grant no.SGDX20201103095412040)Guangdong Major Project of Basic and Applied Basic Research (grant no.2019B030302007).
文摘The precisely customizable attributes of self-assembled monolayers(SAMs)molecules at the atomic level hold the potential to facilitate efficient hole selection and interface passivation simultaneously.However,the correlation between the exposure of passivating groups on the surface and device performance remains unexplored.Herein,we introduce two newly designed SAM molecules,Cbz2S and Cbz2SMe,incorporating cyclic disulfide or two flanking thiomethyls by modifying the 4,5-position of carbazole to adjust the Lewis basicity of the SAM-modified surface.Despite possessing suitable energetic alignment,Cbz2S with more-exposed sulfur atoms exhibited inferior device performance due to excessive reactivity,leading to an overpopulation of PbI2 crystallites at the buried perovskite interface.In contrast,the screening effect from the methyl groups of Cbz2SMe optimized SAM reactivity,exquisitely integrating buried interface passivation and hole selection together.Consequently,the champion inverted perovskite solar cell(PSC)employing Cbz2SMe achieved an impressive power conversion efficiency of 24.42%,accompanied by prolonged stability.This work demonstrates the feasibility of incorporating Lewis-basic passivation groups into SAM molecules and elucidates the relationship between the reactivity of SAM passivation groups and device performance.These findings provide valuable insights for the design of novel multifunctional SAM molecules,further advancing the performance of PSCs.
基金the National Natural Science Foundation of China(Grant Nos.62204078 and U22A2072)the Natural Science Foundation of Henan Province for Excellent Youth Scholar(Grant No.232300421092).
文摘The performance of red InP and blue ZnTeSe-based quantum dots(QDs)and corresponding QD light emitting diodes(QLEDs)has already been improved significantly,whose external quantum efficiencies(EQEs)and luminances have exceeded 20%and 80000 cd m-2,respectively.However,the inferior performance of the green InP-based device hinders the commercialization of full-color Cd-free QLED technology.The ease of oxidation of the highly reactive InP cores leads to high non-radiative recombination and poor photoluminescence quantum yield(PL QY)of the InP-based core/shell QDs,limiting the performance of the relevant QLEDs.Here,we proposed a fluoride-free synthesis strategy to in-situ passivate the InP cores,in which zinc myristate reacted with phosphine dangling bonds to form Zn–P protective layer and protect InP cores from the water and oxygen in the environment.The resultant InP/ZnSe/ZnS core/shell QDs demonstrated a high PL QY of 91%.The corresponding green-emitting electroluminescence devices exhibited a maximum EQE of 12.74%,along with a luminance of over 175000 cd m^(-2)and a long T50@100 cd m^(-2)lifetime of over 20000 h.
