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101.
衬底温度对ZnO薄膜氧缺陷的影响 总被引:2,自引:1,他引:2
采用射频磁控溅射在石英玻璃和单晶硅Si(100)衬底上制备了ZnO薄膜,研究了衬底温度对ZnO薄膜中氧缺陷的影响。实验发现,ZnO薄膜c轴取向性随温度的升高而增强;当衬底温度达到550。C时,XRD谱上仅出现一个强的(002)衍射峰和一个弱的(004)衍射峰,显示ZnO具有优异c轴取向性。同时,随着温度的升高,ZnO薄膜的紫外透射截止边带向高波长方向漂移,其电导率也随衬底温度的升高逐渐增大,表明薄膜中的氧缺陷逐渐增多。这种氧缺陷是由于ZnO的氧平衡分压高于Zn所致,可通过提高溅射气体中氧含量来改善。 相似文献
102.
Yangyang Xu Peilin Deng Guangda Chen Jinxi Chen Ya Yan Kai Qi Hongfang Liu Bao Yu Xia 《Advanced functional materials》2020,30(6)
The rational construction of efficient bifunctional oxygen electrocatalysts is of immense significance yet challenging for rechargeable metal–air batteries. Herein, this work reports a metal–organic framework derived 2D nitrogen‐doped carbon nanotubes/graphene hybrid as the efficient bifunctional oxygen electrocatalyst for rechargeable zinc–air batteries. The as‐obtained hybrid exhibits excellent catalytic activity and durability for the oxygen electrochemical reactions due to the synergistic effect by the hierarchical structure and heteroatom doping. The assembled rechargeable zinc–air battery achieves a high power density of 253 mW cm?2 and specific capacity of 801 mAh gZn?1 with excellent cycle stability of over 3000 h at 5 mA cm?2. Moreover, the flexible solid‐state rechargeable zinc–air batteries assembled by this hybrid oxygen electrocatalyst exhibits a high discharge power density of 223 mW cm?2, which can power 45 light‐emitting diodes and charge a cellphone. This work provides valuable insights in designing efficient bifunctional oxygen electrocatalysts for long‐life metal–air batteries and related energy conversion technologies. 相似文献
103.
104.
Shuo Dou Chung‐Li Dong Zhe Hu Yu‐Cheng Huang Jeng‐lung Chen Li Tao Dafeng Yan Dawei Chen Shaohua Shen Shulei Chou Shuangyin Wang 《Advanced functional materials》2017,27(36)
The activity of electrocatalysts strongly depends on the number of active sites, which can be increased by downsizing electrocatalysts. Single‐atom catalysts have attracted special attention due to atomic‐scale active sites. However, it is a huge challenge to obtain atomic‐scale CoOx catalysts. The Co‐based metal–organic frameworks (MOFs) own atomically dispersed Co ions, which motivates to design a possible pathway to partially on‐site transform these Co ions to active atomic‐scale CoOx species, while reserving the highly porous features of MOFs. In this work, for the first time, the targeted on‐site formation of atomic‐scale CoOx species is realized in ZIF‐67 by O2 plasma. The abundant pores in ZIF‐67 provide channels for O2 plasma to activate the Co ions in MOFs to on‐site produce atomic‐scale CoOx species, which act as the active sites to catalyze the oxygen evolution reaction with an even better activity than RuO2. 相似文献
105.
Development and Simulation of Sulfur‐doped Graphene Supported Platinum with Exemplary Stability and Activity Towards Oxygen Reduction 下载免费PDF全文
Drew Higgins Md Ariful Hoque Min Ho Seo Rongyue Wang Fathy Hassan Ja‐Yeon Choi Mark Pritzker Aiping Yu Jiujun Zhang Zhongwei Chen 《Advanced functional materials》2014,24(27):4325-4336
Sulfur‐doped graphene (SG) is prepared by a thermal shock/quench anneal process and investigated as a unique Pt nanoparticle support (Pt/SG) for the oxygen reduction reaction (ORR). Particularly, SG is found to induce highly favorable catalyst‐support interactions, resulting in excellent half‐cell based ORR activity of 139 mA mgPt ?1 at 0.9 V vs RHE, significant improvements over commercial Pt/C (121 mA mgPt ?1) and Pt‐graphene (Pt/G, 101 mA mgPt ?1). Pt/SG also demonstrates unprecedented stability, maintaining 87% of its electrochemically active surface area following accelerated degradation testing. Furthermore, a majority of ORR activity is maintained, providing 108 mA mgPt ?1, a remarkable 171% improvement over Pt/C (39.8 mA mgPt ?1) and an 89% improvement over Pt/G (57.0 mA mgPt ?1). Computational simulations highlight that the interactions between Pt and graphene are enhanced significantly by sulfur doping, leading to a tethering effect that can explain the outstanding electrochemical stability. Furthermore, sulfur dopants result in a downshift of the platinum d‐band center, explaining the excellent ORR activity and rendering SG as a new and highly promising class of catalyst supports for electrochemical energy technologies such as fuel cells. 相似文献
106.
107.
采用凝胶燃烧-等离子氮杂方法制备了磷灰石型硅酸镧(La9.33Si6O26-1.5xNx)固体电解质,并对氮杂样品进行了XRD、FT-IR和Raman表征,测试了样品的热稳定性及电导率。结果表明:La9.33Si6O26-1.5xNx的六边磷灰石型物相结构不变。氮杂导致硅酸镧晶体结构中[SiO4]的环境发生改变,并影响其振动模式。TG-DSC分析表明氮杂硅酸镧的烧结温度应为1 200℃。在微波功率为300W,作用时间为15min条件下制备的氮杂硅酸镧的烧结体的电导率达1.28×10-2 S.cm-1(800℃)。初步分析认为氮杂导致通道氧空位浓度增加、氧离子迁移速率加快、电导率变大,形成空间电导增强效应。 相似文献
108.
Bingrong Guo Haohao Huo Qixuan Zhuang Xiaoqian Ren Xinxin Wen Bolun Yang Xiaoxiao Huang Qiaowan Chang Siwei Li 《Advanced functional materials》2023,33(25):2300557
Oxygen evolution reaction (OER) is the anodic half-reaction for crucial energy devices, such as water electrolysis, metal–air battery, and electrochemical CO2 reduction. Fe-based materials are recognized as one of the most promising electrocatalysts for OER because of its extremely low price and high activity. In particular, iron oxyhydroxide (FeOOH) is not only highly active toward OER, but also widely accepted as the true active species of Fe-based OER electrocatalysts for plenty of Fe-based materials are converted into FeOOH during OER test. Herein, the recent advances of FeOOH-based nano-structure and its application in OER are reviewed. The relationship between FeOOH structure and its catalytic performance, followed by the introduction of current strategies for enhancing the OER activity (i.e., crystalline phase engineering, element doping, and construction of hybrid materials) is mainly focused. Finally, a summary and perspective about the remaining challenges and future opportunities in this area and further the design of Fe-based OER electrocatalysts are provided. 相似文献
109.
Yixing Li Linlin Yang Yijun Liao Rongzhi Zhao Lianze Ji Rui Su Dake Xu Fuhui Wang 《Advanced functional materials》2023,33(35):2302712
Antibacterial elements and non-contact heating abilities have been proven effective for antibacterial and antibiofilm activities, but it remains a challenge to integrate both within one material. Herein, assisted by the high-entropy effect, FeNiTiCrMnCux high-entropy alloy nanoparticles (HEA-NPs) with excellent photothermal heating properties for boosting antibacterial and antibiofilm performances are synthesized. Benefitting from the synergetic effect of copper ions released and thermal damage by the HEA-NPs, more reactive oxygen species (ROS) are generated, leading to the rupture of the cell membranes and the eradication of the biofilms. As a result, the antibiofilm efficiency (400 µg mL−1) of the mostly optimized FeNiTiCrMnCu1.0 HEA-NPs in the marine nutrient medium, which is the worst-case scenario for the antimicrobial material, can be improved from 81% to 97.4% under 30 min solar irradiation (1 sun). The present study demonstrates a new strategy for effectively treating marine microorganisms that cause biofouling and microbial corrosion using HEA-NPs with photothermal heating characteristics as an antibacterial auxiliary. 相似文献
110.
采用电子束蒸发法制备了单层TiO2薄膜.控制O2流量从10 mL/min以步长10 mL/min递增至50 ml/min(标况下).利用ZYGO干涉仪测量基片镀膜前后的面型变化;采用Stoney公式计算出残余应力,分析了不同O2压下残余应力的变化.在本实验条件下,TiO2薄膜的应力随O2的增大,张应力先增大后减小;随O2压继续增大,由张应力逐渐过渡到压应力;O2压过大时,压应力减小.因此,可以通过改变O2压来控制薄膜的应力.应力的变化与薄膜的微观结构密切相关,分析了所有样品的X射线衍射(XRD)谱发现,薄膜结构均为非晶态. 相似文献