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MgF_(2)助剂对MgAl_(1.9)Ga_(0.1)O_(4)透明陶瓷的制备与光学性能的影响
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作者 吕朝阳 徐勇 +3 位作者 杨久延 涂广升 涂兵田 王皓 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第5期531-538,共8页
MgAl_(1.9)Ga_(0.1)O_(4)透明陶瓷具有优异的光学性能,其制备依赖于高质量坯体的凝胶注模成型和长时间的无压预烧。本研究选择MgF_(2)为烧结助剂,并通过瞬时液相调节无压预烧的致密化过程。采用干压成型、无压预烧和热等静压烧结制备了... MgAl_(1.9)Ga_(0.1)O_(4)透明陶瓷具有优异的光学性能,其制备依赖于高质量坯体的凝胶注模成型和长时间的无压预烧。本研究选择MgF_(2)为烧结助剂,并通过瞬时液相调节无压预烧的致密化过程。采用干压成型、无压预烧和热等静压烧结制备了不同尺寸的MgAl_(1.9)Ga_(0.1)O_(4)透明陶瓷样品,并系统分析了MgF_(2)对材料显微结构、光学和机械性能的影响。研究表明:MgF_(2)在~1230℃熔化形成的液相促使陶瓷的致密度与晶粒尺寸增大,后续烧结过程中残留的MgF_(2)氧化为MgO并固溶进入MgAl_(1.9)Ga_(0.1)O_(4)晶格。添加质量分数0.2%MgF_(2)的2.04 mm厚透明陶瓷样品在紫外和可见光区域具有76.5%~83.4%的直线透过率和较高的光学质量。此外,该陶瓷的特征抗弯强度为167.1 MPa,与细晶MgAl2O4透明陶瓷相近,但是前者的Weibull模数(8.81±0.29)更高。本研究为制备光学性能良好的大尺寸MgAl_(1.9)Ga_(0.1)O_(4)透明陶瓷提供了新的选择。 展开更多
关键词 透明陶瓷 MgAl_(1.9)Ga_(0.1)O_(4) mgf_(2) 瞬时液相烧结 光学性能
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Memristive feature and mechanism induced by laser-doping in defect-free 2D semiconductor materials
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作者 Xiaoshan Du Shu Wang +11 位作者 Qiaoxuan Zhang Shengyao Chen Fengyou Yang Zhenzhou Liu Zhengwei Fan Lijun Ma Lei Wang Lena Du Zhongchang Wang Cong Wang Bing Chen Qian Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第7期85-91,共7页
Memristors as non-volatile memory devices have gained numerous attentions owing to their advantages in storage,in-memory computing, synaptic applications, etc. In recent years, two-dimensional(2D) materials with moder... Memristors as non-volatile memory devices have gained numerous attentions owing to their advantages in storage,in-memory computing, synaptic applications, etc. In recent years, two-dimensional(2D) materials with moderate defects have been discovered to exist memristive feature. However, it is very difficult to obtain moderate defect degree in 2D materials, and studied on modulation means and mechanism becomes urgent and essential. In this work, we realized memristive feature with a bipolar switching and a configurable on/off ratio in a two-terminal MoS_(2) device(on/off ratio ~100), for the first time, from absent to present using laser-modulation to few-layer defect-free MoS_(2)(about 10 layers), and its retention time in both high resistance state and low resistance state can reach 2×10^(4) s. The mechanism of the laser-induced memristive feature has been cleared by dynamic Monte Carlo simulations and first-principles calculations. Furthermore, we verified the universality of the laser-modulation by investigating other 2D materials of TMDs. Our work will open a route to modulate and optimize the performance of 2D semiconductor memristive devices. 展开更多
关键词 2D-material memristor laser doping laser direct writing memristive mechanism
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Selective core-shell doping enabling high performance 4.6 V-LiCoO_(2)
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作者 Yueming Xia Jianrui Feng +6 位作者 Jinhui Li Yan Li Zhengfeng Zhang Xiaoqi Wang Jianli Shao Manling Sui Pengfei Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期684-693,I0015,共11页
Constructing robust surface and bulk structure is the prerequisite for realizing high performance high voltage LiCoO_(2)(LCO).Herein,we manage to synthesize a surface Mg-doping and bulk Al-doping coreshell structured ... Constructing robust surface and bulk structure is the prerequisite for realizing high performance high voltage LiCoO_(2)(LCO).Herein,we manage to synthesize a surface Mg-doping and bulk Al-doping coreshell structured LCO,which demonstrates excellent cycling performance.Half-cell shows 94.2%capacity retention after 100 cycles at 3.0-4.6 V(vs.Li/Li^(+))cycling,and no capacity decay after 300 cycles for fullcell test(3.0-4.55 V).Based on comprehensive microanalysis and theoretical calculations,the degradation mechanisms and doping effects are systematically revealed.For the undoped LCO,high voltage cycling induces severe interfacial and bulk degradations,where cracks,stripe defects,fatigue H2 phase,and spinel phase are identified in grain bulk.For the doped LCO,Mg-doped surface shell can suppress the interfacial degradations,which not only stabilizes the surface structure by forming a thin rock-salt layer but also significantly improves the electronic conductivity,thus enabling superior rate performance.Bulk Al-doping can suppress the lattice"breathing"effect and the detrimental H3 to H1-3 phase transition,which minimizes the internal strain and defects growth,maintaining the layered structure after prolonged cycling.Combining theoretical calculations,this work deepens our understanding of the doping effects of Mg and Al,which is valuable in guiding the future material design of high voltage LCO. 展开更多
关键词 Lithium-ion battery doping effect Failure mechanism High-voltage LiCoO_(2) Electron microscopy
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Enhanced stability of FA-based perovskite:Rare-earth metal compound EuBr_(2) doping
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作者 候敏娜 郭旭 +6 位作者 韩梅斗雪 赵均陶 王志元 丁毅 侯国付 张宗胜 韩小平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期669-675,共7页
It is highly desirable to enhance the long-term stability of perovskite solar cells(PSCs)so that this class of photovoltaic cells can be effectively used for the commercialization purposes.In this contribution,attempt... It is highly desirable to enhance the long-term stability of perovskite solar cells(PSCs)so that this class of photovoltaic cells can be effectively used for the commercialization purposes.In this contribution,attempts have been made to use the two-step sequential method to dope EuBr_(2)into FAMAPbI_(3)perovskite to promote the stability.It is shown that the device durability at 85℃in air with RH of 20%-40%is improved substantially,and simultaneously the champion device efficiency of 23.04%is achieved.The enhancement in stability is attributed to two points:(ⅰ)EuBr_(2)doping effectively inhibits the decomposition andα-δphase transition of perovskite under ambient environment,and(ⅱ)EuBr_(2)aggregates in the oxidized format of Eu(BrO_(3))_(3)at perovskite grain boundaries and surface,hampering humidity erosion and mitigates degradation through coordination with H_(2)O. 展开更多
关键词 EuBr_(2) doping inhibited phase transition and decomposition STABILITY perovskite solar cell
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Nitrogen-doping boosts ^(*)CO utilization and H_(2)O activation on copper for improving CO_(2) reduction to C_(2+) products
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作者 Yisen Yang Zhonghao Tan +5 位作者 Jianling Zhang Jie Yang Renjie Zhang Sha Wang Yi Song Zhuizhui Su 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1459-1465,共7页
To improve the electrocatalytic transformation of carbon dioxide (CO_(2)) to multi-carbon (C_(2+)) products is of great importance.Here we developed a nitrogen-doped Cu catalyst,by which the maximum C_(2+) Faradaic ef... To improve the electrocatalytic transformation of carbon dioxide (CO_(2)) to multi-carbon (C_(2+)) products is of great importance.Here we developed a nitrogen-doped Cu catalyst,by which the maximum C_(2+) Faradaic efficiency can reach 72.7%in flow-cell system,with the partial current density reaching 0.62 A cm^(-2).The in situ Raman spectra demonstrate that the *CO adsorption can be strengthened on such a N-doped Cu catalyst,thus promoting the *CO utilization in the subsequent C–C coupling step.Simultaneously,the water activation can be well enhanced by N doping on Cu catalyst.Owing to the synergistic effects,the selectivity and activity for C_(2+) products over the N-deoped Cu catalyst are much improved. 展开更多
关键词 Electrocatalytic CO_(2)reduction reaction Copper catalyst doping Multi-carbon products In situ Raman measurement
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Homovalent doping:An efficient strategy of the enhanced TiNb_(2)O_(7)anode for lithium-ion batteries
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作者 Xiaohe Jin Yirui Deng +5 位作者 Han Tian Miaomiao Zhou Wenhao Tang Huiyou Dong Xinquan Zhang Ruiping Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1257-1266,共10页
The low energy density,unsatisfied cycling performance,potential safety issue and slow charging kinetics of the commercial lithium-ion batteries restrained their further application in the fields of fast charging and ... The low energy density,unsatisfied cycling performance,potential safety issue and slow charging kinetics of the commercial lithium-ion batteries restrained their further application in the fields of fast charging and long-haul electric vehicles.Monoclinic TiNb_(2)O_(7)(TNO)with the theoretical capacity of 387 mAh g^(-1)has been proposed as a high-capacity anode materials to replace Li4Ti5O12.In this work,homovalent doping strategy was used to enhance the electrochemical performance of TiNb_(2)O_(7)(TNO)by employing Zr to partial substitute Ti through solvothermal method.The doping of Zr^(4+)ions can enlarge the lattice structure without changing the chemical valence of the original elements,refine and homogenize the grains,improve the electrical conductivity,and accelerate the ion diffusion kinetics,and finally enhance the cycle and rate performance.Specifically,Z0.05-TNO shows initial discharge capacity of as high as 312.2 mAh g^(-1)at 1 C and 244.8 mAh g^(-1)at 10 C,and still maintains a high specific capacity of 171.3 mAh g^(-1)after 800 cycles at 10 C.This study provides a new strategy for high-performance fast-charging energy storage electrodes. 展开更多
关键词 Homovalent doping Zr^(4+)TiNb_(2)O_(7) Microsphere Lithium-ion batteries
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Defect Engineering in Earth-Abundant Cu_(2)ZnSnSe_(4) Absorber Using Efficient Alkali Doping for Flexible and Tandem Solar Cell Applications
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作者 Muhammad Rehan Ara Cho +11 位作者 Inyoung Jeong Kihwan Kim Asmat Ullah Jun-Sik Cho Joo Hyung Park Yunae Jo Sung Jun Hong Seung Kyu Ahn SeJin Ahn Jae Ho Yun Jihye Gwak Donghyeop Shin 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期249-256,共8页
To demonstrate flexible and tandem device applications,a low-temperature Cu_(2)ZnSnSe_(4)(CZTSe)deposition process,combined with efficient alkali doping,was developed.First,high-quality CZTSe films were grown at 480℃... To demonstrate flexible and tandem device applications,a low-temperature Cu_(2)ZnSnSe_(4)(CZTSe)deposition process,combined with efficient alkali doping,was developed.First,high-quality CZTSe films were grown at 480℃by a single co-evaporation,which is applicable to polyimide(PI)substrate.Because of the alkali-free substrate,Na and K alkali doping were systematically studied and optimized to precisely control the alkali distribution in CZTSe.The bulk defect density was significantly reduced by suppression of deep acceptor states after the(NaF+KF)PDTs.Through the low-temperature deposition with(NaF+KF)PDTs,the CZTSe device on glass yields the best efficiency of 8.1%with an improved Voc deficit of 646 mV.The developed deposition technologies have been applied to PI.For the first time,we report the highest efficiency of 6.92%for flexible CZTSe solar cells on PI.Additionally,CZTSe devices were utilized as bottom cells to fabricate four-terminal CZTSe/perovskite tandem cells because of a low bandgap of CZTSe(~1.0 eV)so that the tandem cell yielded an efficiency of 20%.The obtained results show that CZTSe solar cells prepared by a low-temperature process with in-situ alkali doping can be utilized for flexible thin-film solar cells as well as tandem device applications. 展开更多
关键词 alkali doping Earth-abundant Cu_(2)ZnSnSe_(4) flexible solar cells four-terminal tandem cells low-temperature process
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Enhancing potassium-ion storage of Bi_(2)S_(3) through external–internal dual synergism: Ti_(3)C_(2)T_(x) compositing and Cu^(2+) doping
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作者 Dawei Sha Yurong You +5 位作者 Rongxiang Hu Jianxiang Ding Xin Cao Yuan Zhang Long Pan ZhengMing Sun 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期39-51,共13页
Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode ... Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode electrode materials.Here,we propose a dual synergic optimization strategy to enhance the K^(+)storage stability and reaction kinetics of Bi_(2)S_(3) through two-dimensional compositing and cation doping.Externally,Bi_(2)S_(3) nanoparticles are loaded onto the surface of three-dimensional interconnected Ti_(3)C_(2)T_(x) nanosheets to stabilize the electrode structure.Internally,Cu^(2+)doping acts as active sites to accelerate K^(+)storage kinetics.Various theoretical simulations and ex situ techniques are used to elucidate the external–internal dual synergism.During discharge,Ti_(3)C_(2)T_(x) and Cu^(2+)collaboratively facilitate K+intercalation.Subsequently,Cu^(2+)doping primarily promotes the fracture of Bi2S3 bonds,facilitating a conversion reaction.Throughout cycling,the Ti_(3)C_(2)T_(x) composite structure and Cu^(2+)doping sustain functionality.The resulting Cu^(2+)-doped Bi2S3 anchored on Ti_(3)C_(2)T_(x)(C-BT)shows excellent rate capability(600 mAh g^(-1) at 0.1 A g^(–1);105 mAh g^(-1) at 5.0 A g^(-1))and cycling performance(91 mAh g^(-1) at 5.0 A g^(-1) after 1000 cycles)in half cells and a high energy density(179 Wh kg–1)in full cells. 展开更多
关键词 Bi_(2)S_(3) cation doping potassium-ion batteries synergic mechanism Ti_(3)C_(2)T_(x)compositing
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5%Ag掺杂对MNO_(2)纳米棒和海胆微球形貌及其甲苯氧化性能的影响
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作者 鲁美娟 方汉孙 +4 位作者 黄华军 李丹萍 吴玮玲 屈小路 喻成龙 《环境工程技术学报》 CAS CSCD 北大核心 2024年第4期1239-1246,共8页
采用水热法制备了MNO_(2)纳米棒和海胆微球,并原位掺杂5%Ag制备了Mn-Ag复合氧化物,利用SEM、XRD、BET、Raman等表征技术对其结构进行表征,并考察不同催化剂对甲苯的去除性能。结果表明:(NH_(4))_(2)S_(2)O_(8)的掺入量会对MNO_(2)的形... 采用水热法制备了MNO_(2)纳米棒和海胆微球,并原位掺杂5%Ag制备了Mn-Ag复合氧化物,利用SEM、XRD、BET、Raman等表征技术对其结构进行表征,并考察不同催化剂对甲苯的去除性能。结果表明:(NH_(4))_(2)S_(2)O_(8)的掺入量会对MNO_(2)的形貌产生影响,当其掺入量为2.28 g时,形成MNO_(2)纳米棒,当其掺入量为6.84 g时,形成MNO_(2)海胆微球;MNO_(2)纳米棒掺杂5%的Ag后,形貌未发生变化,但当MNO_(2)海胆微球掺杂5%Ag时,表面的纳米线较MNO_(2)海胆微球有所增长,且出现了缠绕现象,形成了空心鸟巢状结构;5%Ag掺杂后,对MNO_(2)纳米棒和MNO_(2)海胆微球的晶型未产生影响,均为α-MNO_(2),但5%Ag-MNO_(2)纳米棒出现了Mn2O_(3)的衍射峰;MNO_(2)海胆微球较MNO_(2)纳米棒的比表面积、孔径和孔容均增大,且Ag的掺杂进一步提高了MNO_(2)海胆微球的比表面积、孔径和孔容;MNO_(2)海胆微球比MNO_(2)纳米棒具有更好的甲苯去除性能,且5%Ag掺杂后,MNO_(2)海胆微球对甲苯的去除性能达到最好。 展开更多
关键词 MNO_(2)纳米棒 MNO_(2)海胆微球 AG掺杂 形貌影响 甲苯去除
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MgF_(2)对Mn^(4+)掺杂锗酸盐红色荧光粉发光的影响 被引量:1
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作者 万嘉文 龙林芳 +3 位作者 马道远 刘云正 王梓祥 夏李斌 《无机化学学报》 SCIE CAS CSCD 北大核心 2023年第12期2328-2338,共11页
3.5MgO·0.5MgF_(2)·GeO2∶Mn^(4+)作为优异热稳定性和良好发光性能的红色荧光粉而被市场应用,然而,该粉体中MgF_(2)的作用影响机理尚不明晰,阻碍其性能进一步优化和发展。采用高温固相法制备了系列Mn^(4+)激活的锗酸盐荧光粉... 3.5MgO·0.5MgF_(2)·GeO2∶Mn^(4+)作为优异热稳定性和良好发光性能的红色荧光粉而被市场应用,然而,该粉体中MgF_(2)的作用影响机理尚不明晰,阻碍其性能进一步优化和发展。采用高温固相法制备了系列Mn^(4+)激活的锗酸盐荧光粉,通过对比加入MgF_(2)、H_(3)BO_(3)(助熔剂),研究了该粉体的结构、形貌、发光性能等变化规律,阐明了MgF_(2)的发光影响作用。研究表明,加入MgF_(2)、H_(3)BO_(3)和不加任何助熔剂时的样品,其最佳烧结温度分别为1150、1250和1350℃,上述温度下发光强度均为最佳值,其中加入MgF_(2)、H_(3)BO_(3)的样品在最佳温度处生成了纯相。MgF_(2)的添加,一方面同H_(3)BO_(3)一样作为助熔剂对生成纯相、提高样品结晶度起了积极的作用;另一方面,通过研究分析,确认F-离子成功掺杂进入晶格,促使样品生成的晶体结构为Mg_(14)Ge_(5)(O,F)_(24)。加入MgF_(2)、H_(3)BO_(3)在最佳烧结温度的样品的荧光寿命分别为0.93和0.75 ms。 展开更多
关键词 发光材料 mgf_(2) H_(3)BO_(3) 锗酸盐荧光粉 助熔剂
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Li-Ce共掺杂TiO_(2)纳米材料制备及光催化性能的研究
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作者 李媛 张家豪 王月 《当代化工》 CAS 2024年第10期2419-2422,共4页
选用六水合硝酸铈(Ce(NO_(3))_(3)·6H_(2)O)为掺杂剂,以钛酸四丁酯(TBOT)为原料,采用溶胶-凝胶法制备出铈掺杂改性的TiO_(2)光催化剂,并利用XRD、SEM、Uv-vis等表征方法研究Ce/TiO_(2)催化剂的结构、形貌和其对亚甲基蓝的光催化降... 选用六水合硝酸铈(Ce(NO_(3))_(3)·6H_(2)O)为掺杂剂,以钛酸四丁酯(TBOT)为原料,采用溶胶-凝胶法制备出铈掺杂改性的TiO_(2)光催化剂,并利用XRD、SEM、Uv-vis等表征方法研究Ce/TiO_(2)催化剂的结构、形貌和其对亚甲基蓝的光催化降解性能。结果表明:在500℃退火2 h,Ti与Ce物质的量比为1∶0.01(TiO_(2):0.01Ce)时,样品光催化效率最高,对亚甲基蓝降解率可达93.8%。同时还对TiO_(2):0.01Ce进行Li共掺改良,其光降解率可达95.4%,大于相同条件下单掺杂Ce的光降解率。 展开更多
关键词 溶胶-凝胶法 TiO_(2) 光催化 共掺杂 亚甲基蓝
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Al掺杂对SiO_(2)气凝胶耐高温特性的影响研究
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作者 李伟伟 张继承 +4 位作者 方璐 姚路 魏佳悦 段梦如 苑紫颖 《化工新型材料》 CAS CSCD 北大核心 2024年第7期153-156,共4页
SiO_(2)气凝胶具有成本低、制造工艺简单、化学性质稳定、密度小、超高比表面积等优点,是应用最广泛的高温保温隔热材料。以Si28和Si40为Si源,仲丁醇铝为Al源,乙醇为溶剂,采用酸碱催化、CO_(2)超临界干燥法制备了Al掺杂SiO_(2)气凝胶。... SiO_(2)气凝胶具有成本低、制造工艺简单、化学性质稳定、密度小、超高比表面积等优点,是应用最广泛的高温保温隔热材料。以Si28和Si40为Si源,仲丁醇铝为Al源,乙醇为溶剂,采用酸碱催化、CO_(2)超临界干燥法制备了Al掺杂SiO_(2)气凝胶。结果表明:所得产品高温热处理后均为非晶态无定型结构,无掺杂SiO_(2)气凝胶线收缩率为24.34%,Al掺杂SiO_(2)气凝胶线收缩为14.05%,且在高温热处理后有较大的比表面积和孔体积,说明Al掺杂SiO_(2)气凝胶具有较好的耐高温性能和高温下的绝热性能,这是因为Al元素的掺入使气凝胶在形成过程中产生了很多细小的纳米空洞,热处理过程中Al-Si-O发生化学反应形成双金属氧化物,使气凝胶的氧化物骨架支撑力更强。 展开更多
关键词 掺杂 SiO_(2) 气凝胶 耐高温
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Ce^(3+)掺杂一维多孔SnO_(2)纳米材料的模板合成及光致发光性能
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作者 吕仁江 郝智民 +2 位作者 刘志何 Yasir M 宋铭慧 《化工时刊》 CAS 2024年第5期11-14,共4页
以四氯化锡为金属源,P123为造孔剂,尿素为沉淀剂,无水乙醇为溶剂制备前躯体,以多孔阳极氧化铝(AAO)为模板合成了一维多孔SnO_(2)纳米材料,并采用多种手段进行表征。结果表明:所合成的一维SnO_(2)纳米材料直径大小均匀,具有多孔和四方晶... 以四氯化锡为金属源,P123为造孔剂,尿素为沉淀剂,无水乙醇为溶剂制备前躯体,以多孔阳极氧化铝(AAO)为模板合成了一维多孔SnO_(2)纳米材料,并采用多种手段进行表征。结果表明:所合成的一维SnO_(2)纳米材料直径大小均匀,具有多孔和四方晶相结构,Ce^(3+)离子通过掺杂的方式使其具备良好的光致发光性能。 展开更多
关键词 SnO_(2) 模板合成 Ce^(3+)掺杂 光致发光
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Understand anisotropy dependence of damage evolution and material removal during nanoscratch of MgF_(2) single crystals 被引量:4
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作者 Chen Li Yinchuan Piao +3 位作者 Feihu Zhang Yong Zhang Yuxiu Hu Yongfei Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第1期236-252,共17页
To understand the anisotropy dependence of the damage evolution and material removal during the machining process of MgF_(2) single crystals,nanoscratch tests of MgF_(2) single crystals with different crystal planes a... To understand the anisotropy dependence of the damage evolution and material removal during the machining process of MgF_(2) single crystals,nanoscratch tests of MgF_(2) single crystals with different crystal planes and directions were systematically performed,and surface morphologies of the scratched grooves under different conditions were analyzed.The experimental results indicated that anisotropy considerably affected the damage evolution in the machining process of MgF_(2) single crystals.A stress field model induced by the scratch was developed by considering the anisotropy,which indicated that during the loading process,median cracks induced by the tensile stress initiated and propagated at the front of the indenter.Lateral cracks induced by tensile stress initiated and propagated on the subsurface during the unloading process.In addition,surface radial cracks induced by the tensile stress were easily generated during the unloading process.The stress change led to the deflection of the propagation direction of lateral cracks.Therefore,the lateral cracks propagated to the workpiece surface,resulting in brittle removal in the form of chunk chips.The plastic deformation parameter indicated that the more the slip systems were activated,the more easily the plastic deformation occurred.The cleavage fracture parameter indicated that the cracks propagated along the activated cleavage planes,and the brittle chunk removal was owing to the subsurface cleavage cracks propagating to the crystal surface.Under the same processing parameters,the scratch of the(001)crystal plane along the[100]crystal-orientation was found to be the most conducive to achieving plastic machining of MgF_(2) single crystals.The theoretical results agreed well with the experimental results,which will not only enhance the understanding of the anisotropy dependence of the damage evolution and removal process during the machining of MgF_(2) crystals,but also provide a theoretical foundation for achieving the high-efficiency and low-damage processing of anisotropic single crystals. 展开更多
关键词 anisotropy dependence damage evolution stress field crack propagation NANOSCRATCH mgf_(2)single crystal
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改性TiO_(2)在光电协同下处理偶氮染料废水的研究进展
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作者 班福忱 魏煜 《供水技术》 2024年第2期12-18,共7页
偶氮染料(AZO)是一类难被生物降解的水溶性高分子有机物,近些年来,由于良好的染色性能被广泛应用于印染等相关行业,但AZO废水一旦排入自然水体将会造成重大的环境污染问题。本文主要介绍了不同类型的改性TiO_(2)对AOZ废水的处理效果并... 偶氮染料(AZO)是一类难被生物降解的水溶性高分子有机物,近些年来,由于良好的染色性能被广泛应用于印染等相关行业,但AZO废水一旦排入自然水体将会造成重大的环境污染问题。本文主要介绍了不同类型的改性TiO_(2)对AOZ废水的处理效果并分析了作用原理,对比分析了单一TiO_(2)与改性TiO_(2)的优缺点,积极探索改性TiO_(2)催化剂的催化机理,解析金属和非金属掺杂在其中的具体作用,为今后更加精准地控制掺杂金属或者非金属比例、提高催化剂效率提供科学依据和技术支持。 展开更多
关键词 光电催化 偶氮染料 印染废水 改性TiO_(2) 掺杂
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MgF_(2)掺杂对0.95MgTiO_(3)-0.05CaTiO_(3)陶瓷结构与微波性能的影响
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作者 冉文 刘凡 +1 位作者 李昊 刘绍军 《粉末冶金材料科学与工程》 2023年第3期253-261,共9页
采用传统固相合成法制备Mg F_(2)掺杂0.95MgTiO_(3)-0.05CaTiO_(3)(95MCT)微波陶瓷,结合X射线衍射谱、拉曼光谱、X射线光电子能谱、扫描电镜及矢量网络分析等表征技术,系统研究Mg F_(2)掺杂对95MCT陶瓷烧结温度、晶体结构、微观形貌与... 采用传统固相合成法制备Mg F_(2)掺杂0.95MgTiO_(3)-0.05CaTiO_(3)(95MCT)微波陶瓷,结合X射线衍射谱、拉曼光谱、X射线光电子能谱、扫描电镜及矢量网络分析等表征技术,系统研究Mg F_(2)掺杂对95MCT陶瓷烧结温度、晶体结构、微观形貌与微波性能的影响。结果表明:少量Mg F_(2)掺杂能够促进陶瓷晶粒均匀生长,抑制Ti^(4+)离子向Ti^(3+)离子转变,增强[TiO_(6)]八面体中Ti—O键的结合强度,从而使95MCT陶瓷的品质因子由30 335 GHz提高至89 470 GHz。1 225℃烧结的Mg F_(2)质量分数为1%的95MCT陶瓷具有优异的综合微波性能:相对介电常数ε_(r)约为19.74,品质因子Q×f值约为89 470 GHz,谐振频率温度系数τ_(f)约为-10.2×10^(-6)℃^(-1)。 展开更多
关键词 MgTiO_(3)-CaTiO_(3)陶瓷 mgf_(2)掺杂 [TiO_(6)]八面体 烧结温度 微波性能
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Carbon Doping Triggered Efficient Electrochemical Hydrogen Evolution of Cross-Linked Porous Ru-MoO_(2) Via Solid-Phase Reaction Strategy 被引量:1
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作者 Jialin Cai Jianye Yang +7 位作者 Xin Xie Jie Ding Leyan Liu Wanyu Tian Yushan Liu Zhiyong Tang Baozhong Liu Siyu Lu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期392-400,共9页
The defect-free structure of Mo-based materials is a“double-edged sword”,which endows the material with excellent stability,but limits its chemical versatility and application in electrochemical hydrogen evolution r... The defect-free structure of Mo-based materials is a“double-edged sword”,which endows the material with excellent stability,but limits its chemical versatility and application in electrochemical hydrogen evolution reaction(HER).Carbon doping engineering is an attractive strategy to effectively improve the performance of Mo-based catalyst and maintain their stability.Herein,we report a cross-linked porous carbon-doped MoO_(2)(C–MoO_(2))-based catalyst Ru/C–MoO_(2) for electrochemical HER,which is prepared by the convenient redox solid-phase reaction(SPR)of porous RuO_(2)/Mo_(2)C composite precursor.Theoretical studies reveal that due to the presence of carbon atoms,the electronic structure of C–MoO_(2) has been properly adjusted,and the loaded small Ru nanoparticles provide a fast water dissociation rate and moderate H adsorption strength.In electrochemical studies under a pH-universal environment,Ru/C–MoO_(2) electrocatalyst exhibits a low overpotential at a current density of 10 mA cm^(-2) and has a low Tafel slope.Meanwhile,Ru/C-MoO_(2) has excellent stability for more than 100 h at an initial current density of 100 mA cm^(-2). 展开更多
关键词 carbon doped hydrogen evolution reaction macro-meso-micropore MoO_(2) RU solid-phase reaction
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