共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
氧电极催化剂及缓慢的阴极氧还原动力学是制约低温燃料电池商业化的关键瓶颈因素之一。为此,国内外研究者近年来从提高低温燃料电池氧电极催化剂的催化活性和稳定性、降低催化剂的成本、发展非贵金属氧还原催化剂等方面开展了大量的研究工作,有力地促进了低温燃料电池的发展进程。本文在简要介绍低温燃料电池氧电极反应机理的基础上,从催化剂载体、贵金属及其合金催化剂、金属大环化合物及M-N/C类催化剂和过渡金属硫族化合物类催化剂等方面详细综述了低温燃料电池氧电极催化剂近年来的主要研究进展,并指出了各类催化剂目前尚待解决的问题和发展方向。 相似文献
3.
合成阳离子聚电解质作为新型电极添加剂 ,考察了新型电极添加剂对离子交换膜燃料电池放电性能的影响。实验结果表明在电极中加入适量的新型电极添加剂可显著地提高燃料电池的放电性能。当电极中新型添加剂的含量为 1 .8%时 ,燃料电池的放电电压和电流密度都处于高峰值状态。实验结果还发现电荷密度为45%的聚电解质型电极添加剂对燃料电池放电性能的改性作用与价格昂贵的进口Nafion乳液添加剂的改性作用基本处于同一水平。因此在离子膜燃料电池中可采用廉价易合成的聚电解质型电极添加剂取代Nafion乳液添加剂。 相似文献
4.
5.
6.
质子交换膜燃料电池由于具有能量转换效率高、操作温度低、环境友好等优点而备受人们关注。随着2014年丰田发布燃料电池电动汽车Mirai,带来了新一轮燃料电池及燃料电池汽车的产业化热潮。然而,提升质子交换膜燃料电池的寿命,开发新一代长寿命燃料电池膜电极及燃料电池仍然是本领域的挑战性课题。膜电极(MEA)是质子交换膜燃料电池最核心的部件,其耐久性直接决定着燃料电池的寿命。MEA主要由质子交换膜、催化剂层、气体扩散层三部分组成。本文从质子交换膜、催化剂及载体、气体扩散层三个方面介绍了近年来国内外在提升燃料电池膜电极的寿命(耐久性)方面所做的工作,并对未来的相关研究和发展做了述评及展望。 相似文献
7.
8.
9.
膜电极是质子交换膜燃料电池最为重要的核心部件,其性能直接决定着燃料电池的性能。提高膜电极的性能和功率密度,对于推动燃料电池的商业化进程具有十分重要的意义。通常意义上的膜电极包括质子交换膜、阴极催化层、阳极催化层、阴极气体扩散层和阳极气体扩散层等5个基本单元(常常称之为五合一膜电极),气体扩散层又包括气体扩散材料层和微孔整平层;膜电极的性能取决于材料和制备技术两个方面,制备技术、膜电极的关键组成材料、铂载量都对膜电极的性能和功率密度具有重要影响。近年来,随着催化剂和质子交换膜等关键材料性能的提升,以及制备技术的进步,国内外膜电极的性能得到了大幅度的提升,丰田公司燃料电池的体积功率密度可高达3.2 kW/L。本文将主要从膜电极制备技术的角度(涉及催化剂层和气体扩散层的制备技术等)介绍近年来高性能高功率密度膜电极的研究发展情况,同时介绍国内外在降低膜电极铂载量和开发自增湿膜电极方面的研究进展。 相似文献
10.
11.
12.
The oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) have attracted increasing attention for the sake of clean, renewable, and efficient energy technologies in recent years. The design of ORR/OER bifunctional electrocatalysts is a challenging task in the promotion of highly efficient rechargeable metal-air batteries as well as regenerative fuel cells. Owing to the wide adaptability of different types and ratios of metals in the interlayer space as well as the adjustable interlayer distance, composite materials with layered double hydroxides (LDHs) and their derivatives have recently been registered as electrode materials and catalysts supports for various electrochemical reactions. This study examines the recent development of bifunctional electrocatalysts based on LDHs for ORR/OER to expand the application of LDHs in the field of energy storage and conversion. Various bifunctional electrocatalysts associated with LDHs are discussed in detail to improve their performance. Finally, existing problems and future prospects for improving the performance of LDHs bifunctional electrocatalysts are proposed. 相似文献
13.
《Journal of Energy Chemistry》2017,26(3):422-427
To develop more ideal bifunctional heteroatom-doped carbon electrocatalysts toward the oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) for regenerative fuel cells and rechargeable metal–air batteries, herein, tobacco-derived N-containing ordered mesoporous carbon(N-OMC) electrocatalysts with different N species distributions are designed. Results indicate that the as-prepared N-OMC with more pyrrolic and pyridinic Ns exhibits much higher activities for the ORR and OER than N-OMC with more graphitic N in both acidic and alkaline media, suggesting that the increase of pyrrolic and pyridinic Ns favors the improvement of ORR and OER activities of the N-containing carbon catalysts, and showing a great potential for the designing of more effective, lower-cost ORR and OER bifunctional electrocatalysts for future regenerative fuel cells and rechargeable metal–air batteries. 相似文献
14.
N,P‐Codoped Carbon Networks as Efficient Metal‐free Bifunctional Catalysts for Oxygen Reduction and Hydrogen Evolution Reactions 下载免费PDF全文
Dr. Jintao Zhang Prof. Liangti Qu Prof. Gaoquan Shi Jiangyong Liu Prof. Jianfeng Chen Prof. Liming Dai 《Angewandte Chemie (International ed. in English)》2016,55(6):2230-2234
The high cost and scarcity of noble metal catalysts, such as Pt, have hindered the hydrogen production from electrochemical water splitting, the oxygen reduction in fuel cells and batteries. Herein, we developed a simple template‐free approach to three‐dimensional porous carbon networks codoped with nitrogen and phosphorus by pyrolysis of a supermolecular aggregate of self‐assembled melamine, phytic acid, and graphene oxide (MPSA/GO). The pyrolyzed MPSA/GO acted as the first metal‐free bifunctional catalyst with high activities for both oxygen reduction and hydrogen evolution. Zn–air batteries with the pyrolyzed MPSA/GO air electrode showed a high peak power density (310 W g?1) and an excellent durability. Thus, the pyrolyzed MPSA/GO is a promising bifunctional catalyst for renewable energy technologies, particularly regenerative fuel cells. 相似文献
15.
Kassa B. Ibrahim Meng‐Che Tsai Soressa A. Chala Mulatu K. Berihun Amaha W. Kahsay Taame A. Berhe Wei‐Nien Su Bing‐Joe Hwang 《中国化学会会志》2019,66(8):829-865
Electrochemical energy storage and conversion devices play a key role in the development of clean, sustainable, and efficient energy systems to meet the sustainable growth of our society. However, challenging issues including the sluggish kinetics of oxygen electrode reactions involving the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) are present, limiting the implementation of devices such as metal‐air batteries, water electrolyzers, and regenerative fuel cells. In this review, various monometallic and bimetallic transition metal oxides (TMOs) and hydroxides are summarized in terms of their application for ORR/OER, in which the merits and demerits of various precious metal and carbon‐based metal oxide materials are discussed, with requirements for better electrocatalysts and catalyst support being introduced as well. Following this, different approaches to improve catalytic activity such as the introduction of doping and defects, the manipulation of crystal facets, and the engineering of supports, compositions, and morphologies are summarized in which TMOs with improved ORR/OER catalytic activities can be synthesized, further improving the speed, stability, and polarization of electrochemical energy storage and conversion devices. Finally, perspectives into the improvement of performance and the better understanding of ORR/OER mechanisms for bifunctional electrocatalysts using in situ spectroscopic techniques and density functional theory calculations are also discussed. 相似文献
16.
17.
Yanrong Ren Haiyan Wang Tianyu Zhang Luankexin Ma Pengcheng Ye Yijun Zhong Yong Hu 《中国化学快报》2021,32(7):2243-2248
The development of low-cost and highly efficient bifunctional electrocatalysts toward oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) is of critical importance for clean energy devices such as fuel cells and metal-air batteries.Herein,a sophisticated na nostructure composed of CoS,Co and MoC nanoparticles incorporated in N and S dual-doped porous carbon nanofibers(CoS/Co/MoC-N,SPCNFs) as a high-efficiency bifunctional electrocatalyst is designed and synthesized via an efficient multistep strategy.The as-prepared CoS/Co/MoC-N,S-PCNFs exhibit a positive half-wave potential(E_(1/2)) of0.871 V for ORR and a low overpotential of 289 mV at 10 mA/cm~2 for OER,outperforming the non-noble metal-based catalysts reported.Furthermore,the assembled Zn-air battery based on CoS/Co/MoC-N,SPCNFs delivers an excellent power density(169.1 mW/cm~2),a large specific capacity(819.3 mAh/g) and robust durability,demonstrating the great potential of the as-developed bifunctional electrocatalyst in practical applications.This work is expected to inspire the design of advanced bifunctional nonprecious metal-based electrocatalysts for energy storage. 相似文献
18.
可逆式再生氢氧燃料电池初步研究 总被引:3,自引:0,他引:3
再生氢氧燃料电池(RFC)是一种将水电解技术与氢氧燃料电池技术相结合的可充放电池,使2H2+O2→2H2O+电能与其逆过程得以循环进行,换言之,氢氧燃料电池的燃料氢气和氧化剂氧气可通过水电解技术得以“再生”,起到蓄能作用.RFC主要用于航天领域,与目... 相似文献
19.
20.
Integrated Photoelectrochemical Solar Energy Conversion and Organic Redox Flow Battery Devices 下载免费PDF全文
Wenjie Li Hui‐Chun Fu Dr. Linsen Li Dr. Miguel Cabán‐Acevedo Prof. Jr‐Hau He Prof. Song Jin 《Angewandte Chemie (International ed. in English)》2016,55(42):13104-13108
Building on regenerative photoelectrochemical solar cells and emerging electrochemical redox flow batteries (RFBs), more efficient, scalable, compact, and cost‐effective hybrid energy conversion and storage devices could be realized. An integrated photoelectrochemical solar energy conversion and electrochemical storage device is developed by integrating regenerative silicon solar cells and 9,10‐anthraquinone‐2,7‐disulfonic acid (AQDS)/1,2‐benzoquinone‐3,5‐disulfonic acid (BQDS) RFBs. The device can be directly charged by solar light without external bias, and discharged like normal RFBs with an energy storage density of 1.15 Wh L?1 and a solar‐to‐output electricity efficiency (SOEE) of 1.7 % over many cycles. The concept exploits a previously undeveloped design connecting two major energy technologies and promises a general approach for storing solar energy electrochemically with high theoretical storage capacity and efficiency. 相似文献