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以離散元素法建構高爐佈料之縮尺加速模擬方法;以離散元素法建構高爐佈料之縮尺加速模擬方法

Tue, 20 Oct 2026 07:46:04 GMT

title: 以離散元素法建構高爐佈料之縮尺加速模擬方法;以離散元素法建構高爐佈料之縮尺加速模擬方法 abstract: 本研究以離散元素法模擬高爐料倉與爐喉區域旋轉佈料行為，探討1/2縮尺模型取代全模型進行高爐佈料分析之可行性，並進一步整合romAI、Twin Activate與HyperStudy，建立爐料分布代理模型之快速預測及佈料矩陣最佳化篩選之架構。研究首先比較全模型與1/2縮尺模型之料流軌跡、料面輪廓、礦焦比、孔隙率與粒徑分布等特徵，並分析添加HBI與添加Pellet兩種含鐵爐料條件對料層結構之影響。其次，以EDEM模擬資料建立礦焦比與孔隙率之romAI代理模型，先採用11組模擬資料訓練集進行模型訓練，並以第12組模擬資料作為測試集，再增加5組模擬資料將訓練集擴充至16組，以評估訓練集增加對模型預測能力之影響。最後，透過MELS-DOE、GRSM及局部鄰近搜尋之三階段最佳化流程，分別針對礦焦比與孔隙率之目標徑向分布搜尋最佳佈料矩陣，並將所得矩陣以EDEM重新模擬以進行驗證。模擬結果顯示，1/2縮尺模型可將旋轉滑槽佈料的模擬時間縮短至全模型之約1/3∼1/6，並能合理重現主要爐料流動、料面輪廓及礦焦比與孔隙率徑向分布趨勢。添加Pellet因小粒徑顆粒數量較多，不僅增加計算負荷，亦較容易填入大顆粒間孔隙，使整體孔隙率低於添加HBI。在代理模型方面，訓練集由11組增加至16組後，礦焦比之平均絕對百分比誤差由13.6%降至12.3%，孔隙率則由6.72%降至5.93%，顯示增加訓練集資料有助於改善代理模型預測能力。在最佳化方面，經三階段最佳化後，礦焦比之目標函數(平均絕對百分比誤差， Objective_J)由25.33%降至14.33%，最佳化的礦焦比佈料矩陣為C=[3，4，2，4，2]而含鐵爐料佈料矩陣為Fe=[1，1，5，6，2]；孔隙率由3.39%降至1.69%，最佳化的孔隙率佈料矩陣為C=[2，1，4，5，3]與Fe=[3，3，1，3，5]。將上述最佳化矩陣重新代入EDEM進行模擬後，其Objective_J則分別為19.06%與1.86%。因此，本研究所建立之代理模型暨最佳化流程可有效縮小預測分布與目標分布之差異，並快速識別整體誤差較低之佈料矩陣。綜合而言，本研究所建立之縮尺DEM模型與代理模型最佳化流程，可有效降低高爐佈料分析之計算成本，並作為礦焦比與孔隙率快速預測及佈料矩陣篩選之工具。關鍵字:高爐、旋轉佈料、離散元素法、縮尺模型、料層分布、代理模型、最佳化分析。;This study uses the Discrete Element Method (DEM) to simulate burden flow in blast furnace storage bins and rotating-chute charging in the furnace throat region. The feasibility of using a half-scale model as a substitute for the full-scale model in blast furnace burden distribution analysis is investigated. Furthermore， romAI， Twin Activate， and HyperStudy are integrated to establish a framework for rapid prediction using burden-distribution surrogate models and optimization-based screening of charging matrices. First， the full-scale and half-scale models are compared in terms of burden trajectories， burden surface profiles， ore-to-coke ratio， porosity， and particle-size distribution. The effects of two ferrous burden conditions， namely HBI-added and pellet-added cases， on the burden structure are also investigated. Subsequently， EDEM simulation data are used to construct romAI surrogate models for the ore-to-coke ratio and porosity. Eleven simulation cases are initially used as the training set， while the twelfth simulation case is used as the test set. Five additional simulation cases are then added to expand the training set to 16 cases， thereby evaluating the effect of increasing the training data on model prediction performance. Finally， a three-stage optimization procedure consisting of MELS-DOE， GRSM， and local neighboring search is applied to identify optimal charging matrices for prescribed radial distributions of the ore-to-coke ratio and porosity. The resulting matrices are subsequently re-simulated using EDEM for validation. The simulation results show that the half-scale model reduces the computational time required for rotating-chute charging simulations to approximately one-third to one-sixth of that required by the full-scale model， while reasonably reproducing the major burden flow behavior， burden surface profile， and radial distribution trends of the ore-to-coke ratio and porosity. Compared with the HBI-added case， the pellet-added case contains a larger number of fine particles， which not only increases the computational load but also allows the fine particles to more readily fill the voids between larger particles， resulting in a lower overall porosity. Regarding the surrogate models， when the training set is increased from 11 to 16 cases， the mean absolute percentage error of the ore-to-coke ratio model decreases from 13.6% to 12.3%， while that of the porosity model decreases from 6.72% to 5.93%， indicating that increasing the amount of training data improves the predictive performance of the surrogate models. Regarding optimization， after the three-stage optimization procedure， the objective function， defined as the mean absolute percentage error and denoted by Objective_J， for the ore-to-coke ratio decreases from 25.33% to 14.33%. The optimized coke charging matrix is C=[3，4，2，4，2]， while the optimized ferrous burden charging matrix is Fe=[1，1，5，6，2]. For porosity， Objective_J decreases from 3.39% to 1.69%， with the optimized charging matrices C=[2，1，4，5，3] and Fe=[3，3，1，3，5]. When these optimized matrices are re-simulated using EDEM， the corresponding Objective_J values are 19.06% and 1.86%， respectively. Therefore， the surrogate-model-based optimization procedure developed in this study can effectively reduce the discrepancy between the predicted and target distributions and rapidly identify charging matrices with lower overall errors. Overall， the developed half-scale DEM model and surrogate-model-based optimization procedure can effectively reduce the computational cost of blast furnace burden distribution analysis and serve as a tool for rapid prediction of ore-to-coke ratio and porosity distributions as well as charging-matrix screening. Keywords: Blast furnace， Rotating chute， Discrete Element Method， Scaled model， Burden distribution， Surrogate model， Optimization analysis.

氟化石墨烯多功能設計之雙功能陽極修飾層於高穩定性鋰金屬電池;Multi-Functional Design of Fluorinated Graphene as Dual-Function Anode Modifiers for Highly Stable Lithium Metal Batteries

Tue, 20 Oct 2026 07:46:00 GMT

title: 氟化石墨烯多功能設計之雙功能陽極修飾層於高穩定性鋰金屬電池;Multi-Functional Design of Fluorinated Graphene as Dual-Function Anode Modifiers for Highly Stable Lithium Metal Batteries abstract: 隨著再生能源的蓬勃發展與電動車的普及，電池技術的開發尤為重要，其中鋰金屬電池(Lithium Metal Batteries， LMB)因具備最高理論容量(3860 mAh/g)與最低還原電位(-3.04 V 與標準氫電極相比)而備受關注，然而鋰金屬的固有特性導致其在充放電過程中，容易因為不均勻的鋰沉積而形成枝晶，這不僅會造成嚴重的容量衰減，長期運行後更可能引發安全問題。近期研究指出，將人工固體電解質界面膜（Artificial Solid Electrolyte Interphase，ASEI）引入三維鋰載體(Lithium host)中是一項極具前景的策略。相較於單一功能的改善，這種雙功能的引導機制能顯著增強界面穩定性，有效抑制枝晶生長，進而提升電化學性能。本論文分成三個部分(1) 噴塗法製備氟化石墨烯球的三維結構：為進一步擴大鋰的儲存空間並建構高效的鋰離子傳輸通道，本研究採用噴塗法製備純氟化石墨烯球三維結構。相較於前期研究所採用的電泳沉積法，由於純氟化石墨烯球難以均勻沉積於銅箔表面，需搭配片層輔助沉積，而本研究利用噴塗法則可有效將純氟化石墨烯球均勻塗覆於銅箔表面，成功構築三維結構。其結果顯示氟化石墨烯球的含量越多(Spray-H)，可提供更大的鋰儲存空間及更多鋰離子傳輸路徑，可實現超過400小時的循環壽命並於第 215 次循環時仍維持 88.47 %的庫倫效率。(2)適中氧含量下不同F/N比對氮氟共摻雜石墨烯的協同效應：在先前實驗室的工作中，我們已經初步討論氧含量對於氮氟共摻雜石墨烯的影響，其中我們發現適中氧含量下可以生成較多的Li2O，有效降低成核過電位及較佳的循環穩定性，本研究將接續此部分，探討在適中氧含量下不同F/N比對氮氟共摻雜石墨烯的協同效應，結果顯示，高氮含量促進Li3N的生成，降低成核過電位至62 mV，與最低的總介面阻抗(541.4 Ω)，顯示Li3N能有效改善鋰離子的傳輸，低氮含量則因保有FG基材表面片層間的結合力以及優化的F/N比例，該比例使得SEI層在機械強度(LiF)和Li⁺傳輸(Li3N)之間達到良好的平衡，在循環表現中能穩定超過450小時，第 257 圈的庫倫效率達 93.8%，且修飾層的厚度變化（~4.83 μm）與膨脹率（46.36 %）均為最低。全電池測試(NMC-622//FOMNL)中，第30 次循環後比容量仍超過150 mAh/g，於40 次循環後容量保持率為62 %。(3)梯度結構於雙功能陽極修飾層之研究：本研究採用兩階段製程成功製備梯度結構，並藉由循環前SEM觀察證實梯度結構已成功建構。接著度分析結果顯示，利用EPD沉積FG可獲得良好的接著強度，其中Cu/Au/FG和Cu/Bi/FG的剝離強度分別為2.7 N cm⁻¹和2.9 N cm⁻¹。此外於半電池的測試中顯示，單層金屬擁有最低的成核過電位(Au~49.2 mV、Bi~58.2 mV)，顯示不論是Au與Bi接有良好的親鋰性，其中Bi的梯度結構擁有最佳的循環穩定性(在126 圈時庫倫效率為70.99 %)，顯示梯度結構由下層Bi提供良好的親鋰性，可降低鋰成核能障並引導均勻鋰沉積；上層FG則可作為保護層，降低Bi於長時間循環過程中的流失與劣化，使親鋰性金屬得以持續發揮作用。同時，Bi的導入亦彌補了純FG親鋰性不足的缺點。;With the rapid development of renewable energy and the widespread adoption of electric vehicles， the development of advanced battery technologies has become increasingly important. Among various energy storage systems，lithium metal batteries (LMB) have attracted significant attention because of their ultrahigh theoretical capacity (3860 mAh g⁻¹) and the lowest reduction potential (−3.04 V vs. the standard hydrogen electrode). However， the intrinsic properties of lithium metal often lead to non-uniform lithium deposition during cycling， resulting in lithium dendrite growth. This not only causes severe capacity fading but also raises serious safety concerns during long-term operation. Recently， introducing an artificial solid electrolyte interphase (ASEI) into a three-dimensional lithium host has been considered a promising strategy. Compared with a single-function design， this dual-functional approach can significantly improve interfacial stability， effectively suppress dendrite growth， and enhance the overall electrochemical performance. This study is divided into three parts:(1)3D fluorinated graphene ball structure fabricated by spray coating: To further enlarge the lithium storage space and construct efficient lithium-ion transport pathways， a 3D F-ball structure was fabricated using a spray-coating method.Compared with the electrophoretic deposition (EPD) method adopted in previous studies， where pure F-ball could not be uniformly deposited on the Cu foil without the assistance of graphene sheets， the spray-coating method enabled homogeneous deposition of pure FG spheres onto the Cu substrate， successfully constructing a three-dimensional architecture. The results indicate that a higher F-ball content (Spray-H) provides a larger lithium storage space and more lithium-ion transport pathways， achieving a stable cycling life exceeding 400 h while maintaining a Coulombic efficiency of 88.47% after 215 cycles.(2) Synergistic effect of different F/N ratios in N、F co-doped graphene under moderate oxygen content: In our previous work， the influence of oxygen content on N、F co-doped graphene was preliminarily investigated， and it was found that a moderate oxygen content promoted the formation of Li₂O， thereby reducing the nucleation overpotential and improving cycling stability. Building upon this work， the present study further investigated the synergistic effects of different F/N ratios under moderate oxygen content. The results reveal that a higher nitrogen content promotes the formation of Li₃N， reducing the nucleation overpotential to 62 mV and achieving the lowest total interfacial resistance (541.4 Ω)， indicating that Li₃N effectively facilitates lithium-ion transport. In contrast， the low-nitrogen sample preserved the interlayer bonding of the FG framework and maintained an optimized F/N ratio， enabling the SEI to achieve an optimal balance between mechanical strength provided by LiF and lithium-ion conductivity provided by Li₃N. Consequently， this sample exhibited the best cycling performance， sustaining stable cycling for over 450 h with a Coulombic efficiency of 93.8% after 257 cycles. In addition， it exhibited the smallest coating thickness variation (~4.83 μm) and the lowest expansion ratio (46.36%). In full-cell tests using an NMC-622 cathode (NMC-622//FOMNL)， the discharge capacity remained above 150 mAh g⁻¹ after 30 cycles， with a capacity retention of 62% after 40 cycles.(3)Gradient structure for a dual-functional anode modifier:In this study， a gradient structure was successfully fabricated through a two-step process， and its successful construction was confirmed by pre-cycling SEM observations. Adhesion analysis demonstrated that the EPD of FG provided excellent adhesion strength， with peel strengths of 2.7 and 2.9 N cm⁻¹ for the Cu/Au/FG and Cu/Bi/FG electrodes， respectively. Half-cell measurements further revealed that the single-metal interlayers exhibited the lowest nucleation overpotentials (Au: ~49.2 mV; Bi: ~58.2 mV)， indicating the excellent lithiophilicity of both Au and Bi. Among the gradient-structured electrodes， the Bi-based gradient structure exhibited the best cycling stability， achieving a Coulombic efficiency of 70.99% after 126 cycles. These results indicate that the bottom Bi interlayer provides superior lithiophilicity， effectively reducing the Li nucleation energy barrier and promoting uniform Li deposition， while the top FG layer serves as a protective layer that suppresses the loss and degradation of Bi during prolonged cycling， thereby enabling the lithiophilic metal to maintain its functionality. Furthermore， the incorporation of Bi compensates for the insufficient lithiophilicity of pristine FG.

自支撐NiMo電極的製備及其於高性能無鉑族AEMWE之應用;Fabrication of self-supporting NiMo electrode for high performance platinum-group-metal-free AEMWE

Tue, 20 Oct 2026 07:45:34 GMT

title: 自支撐NiMo電極的製備及其於高性能無鉑族AEMWE之應用;Fabrication of self-supporting NiMo electrode for high performance platinum-group-metal-free AEMWE abstract: 本研究旨在開發適用於陰離子交換膜水電解器（Anion Exchange Membrane Water Electrolyzer， AEMWE）之高效能非貴金屬陰極電極。採用脈衝雷射結合熱還原製程，於鎳網基材上直接製備自支撐式NiMo觸媒，並探討不同前驅液濃度及載體材料對NiMo觸媒形貌與析氫反應（Hydrogen Evolution Reaction， HER）電化學性能之影響，進一步將所製備之NiMo自支撐陰極應用於AEMWE單電池測試。實驗結果顯示，不同前驅液濃度會影響NiMo觸媒於基材表面之覆蓋情形及其HER催化性能，經條件調整後可獲得較佳之電化學表現。載體比較結果顯示，以鎳網作為基材之NiMo自支撐電極具有較低之過電位及較佳之HER催化性能，且電化學交流阻抗分析結果顯示其具有較低之電荷轉移阻抗。最後將最佳化NiMo自支撐電極應用於AEMWE單電池中進行驗證，並以商業Pt/C電極作為對照組。在70 °C及1 M KOH操作條件下，全非貴金屬NiFeMn/NiMo單電池於2.0 V時可達1818.1 mA/cm²之電流密度。研究結果證實，自支撐NiMo電極具有良好之HER電化學性能，並展現其於高效能無鉑族AEMWE水電解製氫技術之應用潛力。;This study aims to develop a high-performance non-precious-metal cathode for anion exchange membrane water electrolyzers (AEMWE). A self-supported NiMo catalyst was directly fabricated on nickel mesh using a pulsed-laser-assisted thermal reduction process. The effects of precursor concentration and substrate material on the morphology and hydrogen evolution reaction (HER) performance of NiMo were investigated. The results showed that precursor concentration affected catalyst coverage and HER activity， while NiMo supported on nickel mesh exhibited lower overpotential and charge-transfer resistance. The optimized NiMo cathode was further applied to an AEMWE single cell and compared with commercial Pt/C.At 70 °C in 1 M KOH， the all-non-precious-metal NiFeMn/NiMo single cell reached a current density of 1818.1 mA/cm² at 2.0 V. These results demonstrate that the self-supported NiMo electrode has strong potential for high-performance non-precious-metal AEMWE applications.

氟化鋰對鈣鈦礦發光二極體正逆偏壓發光特性與交流電驅動穩定性影響之研究;氟化鋰對鈣鈦礦發光二極體正逆偏壓發光特性與交流電驅動穩定性影響之研究

Tue, 20 Oct 2026 07:45:17 GMT

title: 氟化鋰對鈣鈦礦發光二極體正逆偏壓發光特性與交流電驅動穩定性影響之研究;氟化鋰對鈣鈦礦發光二極體正逆偏壓發光特性與交流電驅動穩定性影響之研究 abstract: 目前，交流驅動鈣鈦礦發光二極體仍面臨正逆偏壓下載子傳輸與發光不平衡的問題；此外，多數交流驅動元件為了實現交流電致發光，會導入多層功能層，這可能提高元件的操作電壓，並進一步加劇正逆偏壓之間的發光不平衡。本研究延續實驗室既有之製程參數，製備簡單結構之鈣鈦礦發光二極體，並添加氟化鋰以改善元件於正逆偏壓下之發光差異，以及提升交流驅動下之發光穩定性。結果顯示，未添加氟化鋰時，元件於正偏壓下之最高亮度為12，600cd/m2，且逆偏壓下僅為708.1cd/m2，而導入氟化鋰後，正偏壓下最高亮度提升至14，800 cd/m2，而逆偏壓最高亮度則提升至5，380cd/m2，且元件正逆偏壓亮度差異比由94.4%改善至63.6%。於交流電驅動時，正負半週期之亮度差異亦明顯改善，正負週期的亮度差異比從原先的72.6%改善至42.88%；此外，在操作穩定性方面，交流驅動下之T50約為435秒，高於直流正偏壓與逆偏壓之結果。綜上所述，氟化鋰的導入有助於改善鈣鈦礦發光二極體於正逆偏壓下之發光不平衡問題，進而提升元件於交流驅動下之發光平衡性與操作穩定性，使添加氟化鋰之鈣鈦礦發光二極體具有應用於交流電驅動發光元件之潛力。;Currently， AC-driven perovskite light-emitting diode (PeLED) still face challenges associated with unbalanced carrier transport and light emission under forward and reverse biases. Moreover， most AC-driven devices incorporate multiple functional layers to achieve AC electroluminescence， which may increase the operating voltage and further exacerbate the emission imbalance between the two bias directions. In this study， a simple-structure PeLED was fabricated based on the process parameters previously established in our laboratory， and lithium fluoride (LiF) was introduced to reduce the emission difference between forward and reverse biases and improve the emission stability under AC driving. The results showed that， without LiF， the device exhibited a maximum luminance of 12，600cd/m² under forward bias， whereas the maximum luminance under reverse bias was only 708.1cd/m². After the incorporation of LiF， the maximum luminance increased to 14，800cd/m² under forward bias and 5，380cd/m² under reverse bias， while the luminance difference ratio between the forward and reverse biases decreased from 94.4% to 63.6%. Under AC driving， the luminance difference between the positive and negative half-cycles was also significantly reduced， with the luminance difference ratio decreasing from 72.60% to 42.88%. In addition， in terms of operational stability， the T50 under AC driving was approximately 435s， which was longer than those obtained under DC forward and reverse biases. Overall， the incorporation of LiF effectively mitigated the emission imbalance of PeLED under forward and reverse biases， thereby improving the bidirectional emission balance and operational stability under AC driving. These results demonstrate the potential of LiF-incorporated PeLED for application in AC-driven light-emitting devices.