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DAUNet: Detail-Aware U-Shaped Network for 2D Human Pose Estimation
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作者 Xi Li Yuxin Li +2 位作者 Zhenhua Xiao Zhenghua Huang Lianying Zou 《Computers, Materials & Continua》 SCIE EI 2024年第11期3325-3349,共25页
Human pose estimation is a critical research area in the field of computer vision,playing a significant role in applications such as human-computer interaction,behavior analysis,and action recognition.In this paper,we... Human pose estimation is a critical research area in the field of computer vision,playing a significant role in applications such as human-computer interaction,behavior analysis,and action recognition.In this paper,we propose a U-shaped keypoint detection network(DAUNet)based on an improved ResNet subsampling structure and spatial grouping mechanism.This network addresses key challenges in traditional methods,such as information loss,large network redundancy,and insufficient sensitivity to low-resolution features.DAUNet is composed of three main components.First,we introduce an improved BottleNeck block that employs partial convolution and strip pooling to reduce computational load and mitigate feature loss.Second,after upsampling,the network eliminates redundant features,improving the overall efficiency.Finally,a lightweight spatial grouping attention mechanism is applied to enhance low-resolution semantic features within the feature map,allowing for better restoration of the original image size and higher accuracy.Experimental results demonstrate that DAUNet achieves superior accuracy compared to most existing keypoint detection models,with a mean PCKh@0.5 score of 91.6%on the MPII dataset and an AP of 76.1%on the COCO dataset.Moreover,real-world experiments further validate the robustness and generalizability of DAUNet for detecting human bodies in unknown environments,highlighting its potential for broader applications. 展开更多
关键词 Human pose estimation keypoint detection u-shaped network architecture spatial grouping mechanism
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Comparative analyses of mitogenomes in the social bees with insights into evolution of long inverted repeats in the Meliponini
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作者 Yu-Ran Li Zheng-Wei Wang +1 位作者 Richard T.Corlett Wen-Bin Yu 《Zoological Research》 SCIE CSCD 2024年第1期160-175,共16页
The insect mitogenome is typically a compact circular molecule with highly conserved gene contents.Nonetheless,mitogenome structural variations have been reported in specific taxa,and gene rearrangements,usually the t... The insect mitogenome is typically a compact circular molecule with highly conserved gene contents.Nonetheless,mitogenome structural variations have been reported in specific taxa,and gene rearrangements,usually the tRNAs,occur in different lineages.Because synapomorphies of mitogenome organizations can provide information for phylogenetic inferences,comparative analyses of mitogenomes have been given increasing attention.However,most studies use a very few species to represent the whole genus,tribe,family,or even order,overlooking potential variations at lower taxonomic levels,which might lead to some incorrect inferences.To provide new insights into mitogenome organizations and their implications for phylogenetic inference,this study conducted comparative analyses for mitogenomes of three social bee tribes(Meliponini,Bombini,and Apini)based on the phylogenetic framework with denser taxonomic sampling at the species and population levels.Comparative analyses revealed that mitogenomes of Apini and Bombini are the typical type,while those of Meliponini show diverse variations in mitogenome sizes and organizations.Large inverted repeats(IRs)cause significant gene rearrangements of protein coding genes(PCGs)and rRNAs in Indo-Malay/Australian stingless bee species.Molecular evolution analyses showed that the lineage with IRs have lower dN/dS ratios for PCGs than lineages without IRs,indicating potential effects of IRs on the evolution of mitochondrial genes.The finding of IRs and different patterns of gene rearrangements suggested that Meliponini is a hotspot in mitogenome evolution.Unlike conserved PCGs and rRNAs whose rearrangements were found only in the mentioned lineages within Meliponini,tRNA rearrangements are common across all three tribes of social bees,and are significant even at the species level,indicating that comprehensive sampling is needed to fully understand the patterns of tRNA rearrangements,and their implications for phylogenetic inference. 展开更多
关键词 Social bees PHYLOGENY Mitogenome structure Gene rearrangement inverted repeats
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A U-Shaped Network-Based Grid Tagging Model for Chinese Named Entity Recognition
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作者 Yan Xiang Xuedong Zhao +3 位作者 Junjun Guo Zhiliang Shi Enbang Chen Xiaobo Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第6期4149-4167,共19页
Chinese named entity recognition(CNER)has received widespread attention as an important task of Chinese information extraction.Most previous research has focused on individually studying flat CNER,overlapped CNER,or d... Chinese named entity recognition(CNER)has received widespread attention as an important task of Chinese information extraction.Most previous research has focused on individually studying flat CNER,overlapped CNER,or discontinuous CNER.However,a unified CNER is often needed in real-world scenarios.Recent studies have shown that grid tagging-based methods based on character-pair relationship classification hold great potential for achieving unified NER.Nevertheless,how to enrich Chinese character-pair grid representations and capture deeper dependencies between character pairs to improve entity recognition performance remains an unresolved challenge.In this study,we enhance the character-pair grid representation by incorporating both local and global information.Significantly,we introduce a new approach by considering the character-pair grid representation matrix as a specialized image,converting the classification of character-pair relationships into a pixel-level semantic segmentation task.We devise a U-shaped network to extract multi-scale and deeper semantic information from the grid image,allowing for a more comprehensive understanding of associative features between character pairs.This approach leads to improved accuracy in predicting their relationships,ultimately enhancing entity recognition performance.We conducted experiments on two public CNER datasets in the biomedical domain,namely CMeEE-V2 and Diakg.The results demonstrate the effectiveness of our approach,which achieves F1-score improvements of 7.29 percentage points and 1.64 percentage points compared to the current state-of-the-art(SOTA)models,respectively. 展开更多
关键词 Chinese named entity recognition character-pair relation classification grid tagging u-shaped segmentation network
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Analysis of Progressively Type-Ⅱ Inverted Generalized Gamma Censored Data and Its Engineering Application
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作者 Refah Alotaibi Sanku Dey Ahmed Elshahhat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期459-489,共31页
A novel inverted generalized gamma(IGG)distribution,proposed for data modelling with an upside-down bathtub hazard rate,is considered.In many real-world practical situations,when a researcher wants to conduct a compar... A novel inverted generalized gamma(IGG)distribution,proposed for data modelling with an upside-down bathtub hazard rate,is considered.In many real-world practical situations,when a researcher wants to conduct a comparative study of the life testing of items based on cost and duration of testing,censoring strategies are frequently used.From this point of view,in the presence of censored data compiled from the most well-known progressively Type-Ⅱ censoring technique,this study examines different parameters of the IGG distribution.From a classical point of view,the likelihood and product of spacing estimation methods are considered.Observed Fisher information and the deltamethod are used to obtain the approximate confidence intervals for any unknown parametric function of the suggestedmodel.In the Bayesian paradigm,the same traditional inferential approaches are used to estimate all unknown subjects.Markov-Chain with Monte-Carlo steps are considered to approximate all Bayes’findings.Extensive numerical comparisons are presented to examine the performance of the proposed methodologies using various criteria of accuracy.Further,using several optimality criteria,the optimumprogressive censoring design is suggested.To highlight how the proposed estimators can be used in practice and to verify the flexibility of the proposed model,we analyze the failure times of twenty mechanical components of a diesel engine. 展开更多
关键词 inverted generalized gamma CENSORING spacing function LIKELIHOOD Bayesian optimal plan
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Control of GaN inverted pyramids growth on c-plane patterned sapphire substrates
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作者 Luming Yu Xun Wang +8 位作者 Zhibiao Hao Yi Luo Changzheng Sun Bing Xiong Yanjun Han Jian Wang Hongtao Li Lin Gan Lai Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第6期92-96,共5页
Growth of gallium nitride(GaN)inverted pyramids on c-plane sapphire substrates is benefit for fabricating novel devices as it forms the semipolar facets.In this work,GaN inverted pyramids are directly grown on c-plane... Growth of gallium nitride(GaN)inverted pyramids on c-plane sapphire substrates is benefit for fabricating novel devices as it forms the semipolar facets.In this work,GaN inverted pyramids are directly grown on c-plane patterned sapphire substrates(PSS)by metal organic vapor phase epitaxy(MOVPE).The influences of growth conditions on the surface morphol-ogy are experimentally studied and explained by Wulff constructions.The competition of growth rate among{0001},{1011},and{1122}facets results in the various surface morphologies of GaN.A higher growth temperature of 985 ℃ and a lowerⅤ/Ⅲratio of 25 can expand the area of{}facets in GaN inverted pyramids.On the other hand,GaN inverted pyramids with almost pure{}facets are obtained by using a lower growth temperature of 930℃,a higherⅤ/Ⅲratio of 100,and PSS with pattern arrangement perpendicular to the substrate primary flat. 展开更多
关键词 inverted pyramids GAN MOVPE crystal growth competition model
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Role of self-assembled molecules’anchoring groups for surface defect passivation and dipole modulation in inverted perovskite solar cells
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作者 Xiaoyu Wang Muhammad Faizan +3 位作者 Kun Zhou Xinjiang Wang Yuhao Fu Lijun Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期108-115,共8页
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 b... 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. 展开更多
关键词 inverted perovskite solar cell defect passivation self-assembled molecule interface engineering first-principles calculation
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Efficient and Stable Inverted Perovskite Solar Modules Enabled by Solid-Liquid Two-Step Film Formation
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作者 Juan Zhang Xiaofei Ji +13 位作者 Xiaoting Wang Liujiang Zhang Leyu Bi Zhenhuang Su Xingyu Gao Wenjun Zhang Lei Shi Guoqing Guan Abuliti Abudula Xiaogang Hao Liyou Yang Qiang Fu Alex K.‑Y.Jen Linfeng Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期571-582,共12页
A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells.The control of forming uniform and large-area film and perovskite crystallization is still the mai... A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells.The control of forming uniform and large-area film and perovskite crystallization is still the main obstacle restricting the efficiency of PSMs.In this work,we adopted a solid-liquid two-step film formation technique,which involved the evaporation of a lead iodide film and blade coating of an organic ammonium halide solution to prepare perovskite films.This method possesses the advantages of integrating vapor deposition and solution methods,which could apply to substrates with different roughness and avoid using toxic solvents to achieve a more uniform,large-area perovskite film.Furthermore,modification of the NiO_(x)/perovskite buried interface and introduction of Urea additives were utilized to reduce interface recombination and regulate perovskite crystallization.As a result,a large-area perovskite film possessing larger grains,fewer pinholes,and reduced defects could be achieved.The inverted PSM with an active area of 61.56 cm^(2)(10×10 cm^(2)substrate)achieved a champion power conversion efficiency of 20.56%and significantly improved stability.This method suggests an innovative approach to resolving the uniformity issue associated with large-area film fabrication. 展开更多
关键词 inverted perovskite solar cells Perovskite solar modules Two-step film formation CRYSTALLIZATION Defect passivation
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A Nonlinear Explicit Model of A Non-Circular Subsea Tunnel-Liner System with An FGM Inverted Arch Under Mechanical Loading and Fire Fields
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作者 HE Jie CHANG Guo-yong +1 位作者 LIU Yang LI Zhao-chao 《China Ocean Engineering》 SCIE EI CSCD 2024年第5期855-865,共11页
This paper proposes an explicit scheme to analyze the failure of a subsea polyhedral tunnel-liner system with an inverted arch under mechanical loading and fire fields.The thin-walled liner is made of Functionally Gra... This paper proposes an explicit scheme to analyze the failure of a subsea polyhedral tunnel-liner system with an inverted arch under mechanical loading and fire fields.The thin-walled liner is made of Functionally Graded Materials(FGMs),which may improve the stability behavior of the tunnel-liner system.Hydrostatic pressure is inevitable in the liner since underground water may penetrate the cracks of the tunnel,and reach the outer surface of the liner.In addition,an elevated temperature loading is taken into account,considering that fire may occur in the tunnel-liner system.Under the combination of mechanical loading and thermal loading,the liner deforms into a single-lobe shape,which is depicted by a trigonometric function.The total potential energy is expressed quantitatively after the energy approach and thin-walled shell theory are used.The minimum potential energy is obtained when the critical buckling occurs.The critical buckling pressure is calculated,which considers the effect of the thermal field.The present analytical prediction is subsequently compared precisely with other closed-form solutions.Finally,the effects of several parameters,such as the geometric shapes,temperature variations,and volume fraction indices,are discussed to further survey the buckling performance of the nonlinear buckling of an FGM polyhedral liner with an inverted arch.One may address a polyhedral liner with fewer polyhedral sides,and a lower volume fraction index is recommended to rehabilitate cracked tunnels in engineering applications. 展开更多
关键词 tunnel-liner system with an inverted arch volume fraction index mechanical and thermal loadings rehabilitation BUCKLING
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Non-destructive buffer enabling near-infrared-transparent inverted inorganic perovskite solar cells toward 1400 h light-soaking stable perovskite/Cu(In,Ga)Se_(2) tandem solar cells
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作者 Yu Zhang Zhaoheng Tang +14 位作者 Zhongyang Zhang Jiahong Tang Minghua Li Siyuan Zhu Wenyan Tan Xi Jin Tongsheng Chen Jinsong Hu Chao Zhou Chunlei Yang Qijie Liang Xugang Guo Weimin Li Weiqiang Chen Yan Jiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期622-629,I0013,共9页
Near-infrared(NIR)transparent inverted all-inorganic perovskite solar cells(PSCs)are excellent top cell candidates in tandem applications.An essential challenge is the replacement of metal contacts with transparent co... Near-infrared(NIR)transparent inverted all-inorganic perovskite solar cells(PSCs)are excellent top cell candidates in tandem applications.An essential challenge is the replacement of metal contacts with transparent conductive oxide(TCO)electrodes,which requires the introduction of a buffer layer to prevent sputtering damage.In this study,we show that the conventional buffers(i.e.,small organic molecules and atomic layer deposited metal oxides)used for organic-inorganic hybrid perovskites are not applicable to all-inorganic perovskites,due to non-uniform coverage of the vulnerable layers underneath,deterioration upon ion bombardment and moisture induced perovskite phase transition,A thin film of metal oxide nanoparticles by the spin-coating method serves as a non-destructive buffer layer for inorganic PSCs.All-inorganic inverted near-infrared-transparent PSCs deliver a PCE of 17.46%and an average transmittance of 73.7%between 780 and 1200 nm.In combination with an 18.56%Cu(In,Ga)Se_(2) bottom cell,we further demonstrate the first all-inorganic perovskite/CIGS 4-T tandem solar cell with a PCE of 24.75%,which exhibits excellent illumination stability by maintaining 86.7%of its initial efficiency after 1400 h.The non-destructive buffer lays the foundation for efficient and stable NIR-transparent inverted inorganic perovskite solar cells and perovskite-based tandems. 展开更多
关键词 CsPbI_(3)perovskite inverted perovskite solar cells Tandem solar cells Buffer layer Stability
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Reduced-Order Observer-Based LQR Controller Design for Rotary Inverted Pendulum
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作者 Guogang Gao LeiXu +2 位作者 Tianpeng Huang Xuliang Zhao Lihua Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期305-323,共19页
The Rotary Inverted Pendulum(RIP)is a widely used underactuated mechanical system in various applications such as bipedal robots and skyscraper stabilization where attitude control presents a significant challenge.Des... The Rotary Inverted Pendulum(RIP)is a widely used underactuated mechanical system in various applications such as bipedal robots and skyscraper stabilization where attitude control presents a significant challenge.Despite the implementation of various control strategies to maintain equilibrium,optimally tuning control gains to effectively mitigate uncertain nonlinearities in system dynamics remains elusive.Existing methods frequently rely on extensive experimental data or the designer’s expertise,presenting a notable drawback.This paper proposes a novel tracking control approach for RIP,utilizing a Linear Quadratic Regulator(LQR)in combination with a reduced-order observer.Initially,the RIP system is mathematically modeled using the Newton-Euler-Lagrange method.Subsequently,a composite controller is devised that integrates an LQR for generating nominal control signals and a reduced-order observer for reconstructing unmeasured states.This approach enhances the controller’s robustness by eliminating differential terms from the observer,thereby attenuating unknown disturbances.Thorough numerical simulations and experimental evaluations demonstrate the system’s capability to maintain balance below50Hz and achieve precise tracking below1.4 rad,validating the effectiveness of the proposed control scheme. 展开更多
关键词 Rotary inverted pendulum(RIP) linear quadratic regulator(LQR) reduced-order observer states estimate
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Fast and Balanced Charge Transport Enabled by Solution-Processed Metal Oxide Layers for Efficient and Stable Inverted Perovskite Solar Cells
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作者 Jing Zhang James Mcgettrick +11 位作者 Kangyu Ji Jinxin Bi Thomas Webb Xueping Liu Dongtao Liu Aobo Ren Yuren Xiang Bowei Li Vlad Stolojan Trystan Watson Samuel D.Stranks Wei Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期240-248,共9页
Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocol... Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocols,high-temperature heating process,incompatible solvents,etc.),it is still challenging to achieve efficient and reliable all-metal-oxide-based devices.Here,we developed efficient inverted PSCs(IPSCs)based on solution-processed nickel oxide(NiO_(x))and tin oxide(SnO_(2))nanoparticles,working as hole and electron transport materials respectively,enabling a fast and balanced charge transfer for photogenerated charge carriers.Through further understanding and optimizing the perovskite/metal oxide interfaces,we have realized an outstanding power conversion efficiency(PCE)of 23.5%(the bandgap of the perovskite is 1.62 eV),which is the highest efficiency among IPSCs based on all-metal-oxide charge transport materials.Thanks to these stable metal oxides and improved interface properties,ambient stability(retaining 95%of initial PCE after 1 month),thermal stability(retaining 80%of initial PCE after 2 weeks)and light stability(retaining 90%of initial PCE after 1000 hours aging)of resultant devices are enhanced significantly.In addition,owing to the low-temperature fabrication procedures of the entire device,we have obtained a PCE of over 21%for flexible IPSCs with enhanced operational stability. 展开更多
关键词 fast and balanced charge transfer inverted perovskite solar cells long-term stability low-temperature processing metal oxides
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Chlorine-Substituent Regulation in Dopant-Free Small-Molecule Hole-Transport Materials Improves the Effi ciency and Stability of Inverted Perovskite Solar Cells
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作者 Xinyi Liu Xiaoye Zhang +7 位作者 Zhanfeng Li Jinbo Chen Yanting Tian Baoyou Liu Changfeng Si Gang Yue Hua Dong Zhaoxin Wu 《Transactions of Tianjin University》 EI CAS 2024年第4期314-323,共10页
Although doped hole-transport materials(HTMs)off er an effi ciency benefi t for perovskite solar cells(PSCs),they inevi-tably diminish the stability.Here,we describe the use of various chlorinated small molecules,spec... Although doped hole-transport materials(HTMs)off er an effi ciency benefi t for perovskite solar cells(PSCs),they inevi-tably diminish the stability.Here,we describe the use of various chlorinated small molecules,specifi cally fl uorenone-triphenylamine(FO-TPA)-x-Cl[x=para,meta,and ortho(p,m,and o)],with diff erent chlorine-substituent positions,as dopant-free HTMs for PSCs.These chlorinated molecules feature a symmetrical donor-acceptor-donor structure and ideal intramolecular charge transfer properties,allowing for self-doping and the establishment of built-in potentials for improving charge extraction.Highly effi cient hole-transfer interfaces are constructed between perovskites and these HTMs by strategi-cally modifying the chlorine substitution.Thus,the chlorinated HTM-derived inverted PSCs exhibited superior effi ciencies and air stabilities.Importantly,the dopant-free HTM FO-TPA-o-Cl not only attains a power conversion effi ciency of 20.82% but also demonstrates exceptional stability,retaining 93.8%of its initial effi ciency even after a 30-day aging test conducted under ambient air conditions in PSCs without encapsulation.These fi ndings underscore the critical role of chlorine-substituent regulation in HTMs in ensuring the formation and maintenance of effi cient and stable PSCs. 展开更多
关键词 Hole-transport materials inverted perovskite solar cells Chlorinated small molecules Donor–acceptor–donor structure
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High-Performance Inverted Perovskite Solar Cells with Sol-Gel-Processed Sliver-Doped NiO_(x)Hole Transporting Layer
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作者 Haibin Wang Zhiyin Qin +2 位作者 Xinjian Li Chun Zhao Chao Liang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第4期205-214,共10页
Nickel oxide(NiO_(x))has been established as a highly efficient and stable holetransporting layer(HTL)in perovskite solar cells(PSCs).However,existing deposition methods for NiO_(x)have been restricted by high-vacuum ... Nickel oxide(NiO_(x))has been established as a highly efficient and stable holetransporting layer(HTL)in perovskite solar cells(PSCs).However,existing deposition methods for NiO_(x)have been restricted by high-vacuum processes and fail to address the energy level mismatch at the NiO_(x)/perovskite interface,which has impeded the development of PSCs.Accordingly,we explored the application of NiO_(x)as a hybrid HTL through a sol-gel process,where a NiO_(x)film was pre-doped with Ag ions,forming a p/p^(+)homojunction in the NiO_(x)-based inverted PSCs.This innovative approach offers two synergistic advantages,including the enlargement of the built-in electric field for facilitating charge separation,optimizing energy level alignment,and charge transfer efficiency at the interface between the perovskite and HTL.Incorporating this hybrid HTL featuring the p/p^(+)homojunction in the inverted PSCs resulted in a high-power conversion efficiency(PCE)of up to 19.25%,significantly narrowing the efficiency gap compared to traditional n-i-p devices.Furthermore,this innovative strategy for the HTL enhanced the environmental stability to 30 days,maintaining 90%of the initial efficiency. 展开更多
关键词 Ag-NiO_(x)/NiO_(x) hole transporting layer inverted perovskite solar cells
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High-Performance and Large-Area Inverted Perovskite Solar Cells Based on NiO_(x) Films Enabled with A Novel Microstructure-Control Technology
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作者 Guibin Shen Xin Li +7 位作者 Yuqin Zou Hongye Dong Dongping Zhu Yanglin Jiang Xin Ren Ng Fen Lin Peter Müller-Buschbaum Cheng Mu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期153-159,共7页
The improvement in the efficiency of inverted perovskite solar cells(PSCs)is significantly limited by undesirable contact at the NiO_(x)/perovskite interface.In this study,a novel microstructure-control technology is ... The improvement in the efficiency of inverted perovskite solar cells(PSCs)is significantly limited by undesirable contact at the NiO_(x)/perovskite interface.In this study,a novel microstructure-control technology is proposed for fabrication of porous NiO_(x)films using Pluronic P123 as the structure-directing agent and acetylacetone(AcAc)as the coordination agent.The synthesized porous NiO_(x)films enhanced the hole extraction efficiency and reduced recombination defects at the NiO_(x)/perovskite interface.Consequently,without any modification,the power conversion efficiency(PCE)of the PSC with MAPbl_(3)as the absorber layer improved from 16.50%to 19.08%.Moreover,the PCE of the device composed of perovskite Cs0.05(MA_(0.15)FA_(0.85))_(0.95)Pb(I_(0.85)Br_(0.15))_(3)improved from 17.49%to 21.42%.Furthermore,the application of the fabricated porous NiO_(x)on fluorine-doped tin oxide(FTO)substrates enabled the fabrication of large-area PSCs(1.2 cm^(2))with a PCE of 19.63%.This study provides a novel strategy for improving the contact at the NiO_(x)/perovskite interface for the fabrication of high-performance large-area perovskite solar cells. 展开更多
关键词 interfacial contact inverted and large-area perovskite solar cells photovoltaic materials porous NiO_(x)films renewable energy
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Ecofriendly Hydroxyalkyl Cellulose Additives for Efficient and Stable MAPbI_(3)-Based Inverted Perovskite Solar Cells 被引量:1
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作者 Xuefeng Zhu Rui Lin +5 位作者 Hao Gu Huichao Hu Zheng Liu Guichuan Xing Yibing Wu Xinhua Ouyang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第5期251-259,共9页
Perovskite solar cells(PSCs)have been demonstrated to be one of the most promising technologies in the field of renewable energy.However,the presence of the defects in the perovskite films greatly limits the efficienc... Perovskite solar cells(PSCs)have been demonstrated to be one of the most promising technologies in the field of renewable energy.However,the presence of the defects in the perovskite films greatly limits the efficiency and the stability of the PSCs.The additive engineering is one of the most effective approaches to overcome this problem.Most of the successful additives are extracted from the petroleum-based materials,while the research on the biomass-based additives is still lagging behind.In this paper,two ecofriendly hydroxyalkyl cellulose additives,i.e.,hydroxyethyl cellulose(HEC)and hydroxylpropyl cellulose(HPC),are investigated on the performance of the MAPbl_(3)-based inverted PSCs.Due to the strong interaction between the hydroxyl groups of the cellulose and the divalent cations of the perovskite,these additives enhance the crystal grain orientation and significantly repair the defects of the perovskite films.Working as the additives,these two cellulose derivatives show a strong passivation ability,which significantly reduces the trap density and improves the optoelectronic feature of the PSCs.Compared with the average power conversion efficiency(PCE)of the control device(19.19%),an enhancement of~10%is achieved after the addition of HEC.The optimized device(PCE=21.25%)with a long-term stability(10:80 h,PCE=20.93%)is achieved by the incorporation of the HEC additives into the precursor solution.It is the best performance among the PSCs with the cellulose additives up to now.This research provides a novel choice to develop a cost-effective and renewable additive for the PSCs with high efficiency and excellent long-term stability. 展开更多
关键词 ADDITIVES hydroxyalkyl cellulose inverted perovskite solar cells MAPbl_(3)
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Intrinsic thermal stability of inverted perovskite solar cells based on electrochemical deposited PEDOT 被引量:3
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作者 Congtan Zhu Jing Gao +2 位作者 Tian Chen Xueyi Guo Ying Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期445-453,I0011,共10页
Thermal stability of perovskite materials is an issue impairing the long-term operation of inverted perovskite solar cells(PSCs). Herein, the thermal attenuation mechanism of the MAPb I3films that deposited on two dif... Thermal stability of perovskite materials is an issue impairing the long-term operation of inverted perovskite solar cells(PSCs). Herein, the thermal attenuation mechanism of the MAPb I3films that deposited on two different hole transport layers(HTL), poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS) and poly(3,4-ethylenedioxythiophene)(PEDOT), is comprehensively studied by applying a heat treatment at 85℃. The thermal stress causes the mutual ions migration of I, Pb and Ag through the device, which leads to the thermal decomposition of perovskite to form Pb I2. Interestingly, we find that I ions tend to migrate more towards electron transport layer(ETL) during heating, which is different with the observation of I ions migration towards HTL when bias pressure is applied. Moreover, the use of electrochemical deposited PEDOT as HTL significantly decreases the defect density of MAPb I3films as compared to PEDOT:PSS supported one. The electrochemical deposition PEDOT has good carrier mobility and low acidity, which avoids the drawbacks of aqueous PEDOT:PSS. Accordingly, the inverted PSCs based on PEDOT show superior durability than that with PEDOT:PSS. Our results reveal detailed degradation routes of a new kind of inverted PSCs which can contribute to the understanding of the failure of thermal-aged inverted PSCs. 展开更多
关键词 inverted perovskite solarcells CH_(3)NH_(3)Pbl_(3) Thermal stability Electrochemical deposition PEDOT
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Recent progress of inverted organic-inorganic halide perovskite solar cells 被引量:1
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作者 Dongyang Li Yulan Huang +4 位作者 Zhiwei Ren Abbas Amini Aleksandra B.Djurišic Chun Cheng Gang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期168-191,共24页
In recent years,inverted perovskite solar cells(IPSCs)have attracted significant attention due to their low-temperature and cost-effective fabrication processes,hysteresis-free properties,excellent stability,and wide ... In recent years,inverted perovskite solar cells(IPSCs)have attracted significant attention due to their low-temperature and cost-effective fabrication processes,hysteresis-free properties,excellent stability,and wide application.The efficiency gap between IPSCs and regular structures has shrunk to less than 1%.Over the past few years,IPSC research has mainly focused on optimizing power conversion efficiency to accelerate the development of IPSCs.This review provides an overview of recent improvements in the efficiency of IPSCs,including interface engineering and novel film production techniques to overcome critical obstacles.Tandem and integrated applications of IPSCs are also summarized.Furthermore,prospects for further development of IPSCs are discussed,including the development of new materials,methods,and device structures for novel IPSCs to meet the requirements of commercialization. 展开更多
关键词 inverted perovskite solar cells Interface engineering Additive engineering Tandem solar cells Integrated solar cells
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Thermally Evaporated ZnSe for Efficient and Stable Regular/Inverted Perovskite Solar Cells by Enhanced Electron Extraction 被引量:1
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作者 Xin Li Guibin Shen +6 位作者 Xin Ren Ng Zhiyong Liu Yun Meng Yongwei Zhang Cheng Mu Zhi Gen Yu Fen Lin 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第5期440-448,共9页
Electron transport layers(ETLs)are crucial for achieving efficient and stable planar perovskite solar cells(PSCs).Reports on versatile inorganic ETLs using a simple film fabrication method and applicability for both l... Electron transport layers(ETLs)are crucial for achieving efficient and stable planar perovskite solar cells(PSCs).Reports on versatile inorganic ETLs using a simple film fabrication method and applicability for both low-cost planar regular and inverted PSCs with excellent efficiencies(>22%)and high stability are very limited.Herein,we employ a novel inorganic ZnSe as ETL for both regular and inverted PSCs to improve the efficiency and stability using a simple thermal evaporation method.The TiO_(2)-ZnSe-FAPbl_(3)heterojunction could be formed,resulting in an improved charge collection and a decreased carrier recombination further proved through theoretical calculations.The optimized regular PSCs based on TiO_(2)/ZnSe have achieved 23.25%efficiency with negligible hysteresis.In addition,the ZnSe ETL can also effectively replace the unstable bathocuproine(BCP)in inverted PSCs.Consequently,the ZnSe-based inverted device realizes a champion efficiency of 22.54%.Moreover,the regular device comprising the TiO_(2)/ZnSe layers retains 92%of its initial PCE after 10:00 h under 1 Sun continuous illumination and the inverted device comprising the C_(60)/ZnSe layers maintains over 85%of its initial PCE at 85℃for 10:00 h.This highlights one of the best results among universal ETLs in both regular and inverted perovskite photovoltaics. 展开更多
关键词 high efficiency long-term stability planar regular/inverted perovskite solar cells thermal evaporation ZnSe electron transport layer
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Effect of mold and core preheating temperature on corrosion resistance of casting Al-12Si alloy U-shaped cooling channel
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作者 Guang-long Li Jie Zhang +3 位作者 Meng-yu Wang Rui-ming Su Yang Cao Ying-dong Qu 《China Foundry》 SCIE CAS CSCD 2023年第3期218-224,共7页
Temperature has an important impact on the corrosion resistance of mold with cooling channels prepared by casting method.The effect of preheating temperature of the mold and the carbon fiber core on the roughness and ... Temperature has an important impact on the corrosion resistance of mold with cooling channels prepared by casting method.The effect of preheating temperature of the mold and the carbon fiber core on the roughness and corrosion resistance of U-shaped cooling channels made of Al-12Si alloy was examined in depth.The experimental results suggest that as the preheating temperature increased from 273 K to 573 K,the roughness of the inner wall of the cooling channel reduced from 96.6μm to 77.0μm.When the preheating temperature continued to increase to 723 K,the roughness increased to 85.3μm.The wetting between the Al melt and the carbon fiber will reduce micro bubbles and waves on the channel wall as the preheating temperature rises,thereby reducing the roughness.However,with the further increase of preheating temperature,it will increase the solidification time of the Al melt.At this time,the carbon fiber and Al melt will take more time to react,which increases the roughness of the channel wall to a certain extent.The results of exfoliation corrosion show that the larger roughness will aggravate exfoliation corrosion.The prolongation of high temperature reaction time between the carbon fiber and the Al melt will lead to the segregation of Si,which is easy to cause intergranular corrosion.Therefore,reasonable preheating temperature has an important impact on the roughness and corrosion resistance of U-shaped cooling channels. 展开更多
关键词 u-shaped cooling channels ROUGHNESS exfoliation corrosion intergranular corrosion
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Enhancing performance of inverted quantum-dot light-emitting diodes based on a solution-processed hole transport layer via ligand treatment
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作者 Depeng Li Jingrui Ma +8 位作者 Wenbo Liu Guohong Xiang Xiangwei Qu Siqi Jia Mi Gu Jiahao Wei Pai Liu Kai Wang Xiaowei Sun 《Journal of Semiconductors》 EI CAS CSCD 2023年第9期68-74,共7页
The performance of inverted quantum-dot light-emitting diodes(QLEDs)based on solution-processed hole transport layers(HTLs)has been limited by the solvent-induced damage to the quantum dot(QD)layer during the spin-coa... The performance of inverted quantum-dot light-emitting diodes(QLEDs)based on solution-processed hole transport layers(HTLs)has been limited by the solvent-induced damage to the quantum dot(QD)layer during the spin-coating of the HTL.The lack of compatibility between the HTL’s solvent and the QD layer results in an uneven surface,which negatively impacts the overall device performance.In this work,we develop a novel method to solve this problem by modifying the QD film with 1,8-diaminooctane to improve the resistance of the QD layer for the HTL’s solvent.The uniform QD layer leads the inverted red QLED device to achieve a low turn-on voltage of 1.8 V,a high maximum luminance of 105500 cd/m2,and a remarkable maximum external quantum efficiency of 13.34%.This approach releases the considerable potential of HTL materials selection and offers a promising avenue for the development of high-performance inverted QLEDs. 展开更多
关键词 quantum dots quantum-dot light-emitting diodes inverted structure ligand treatment
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