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1.
近来,廉价而丰富的磷化物逐渐引起人们的关注,过渡金属磷化物(TMPs)由于其独特的类金属理化性质、高电导率和良好的催化性能而非常具有吸引力,广泛应用于冶金、加氢处理、电催化、能量储存、光催化等领域,成为催化材料领域的热点。本文主要综述了TMPs的结构特征、常用的制备方法以及在加氢精制、电催化和光催化方面应用的最新进展。  相似文献   

2.
正过渡金属磷化物(TMPs),由于具有独特的物理化学性质,在电解水、燃料电池、金属空气电池等能源电催化领域展现出极大的应用潜力。理论研究表明,由于磷(P)原子半径较大,P的引入使金属原子间距相对增加,原子间相互作用减弱,导致金属d带收缩,费米能级附近态密度增加~(1,2)。因此,  相似文献   

3.
过渡金属磷化物(TMPs)价廉易得,因其独特的结构特征具有丰富的活性位点、良好的导电性和结构稳定性,逐渐在催化领域引起了人们的广泛关注,被应用于有机物硫化、脱氢、电催化、光催化等方面.本文主要综述了过渡金属磷化物的结构特征、常用的制备方法以及在电催化和光催化方向应用的最新进展.  相似文献   

4.
Xuebin Yu 《物理化学学报》2020,36(7):1912032-0
正纳米过渡金属磷化物(MP_x,M=Cu,Ni,Fe,等)在电催化,光催化,超级电容器以及锂离子电池等领域具有很大的应用前景~(1–3)。在储锂应用中,过渡金属磷化物的理论容量与磷的含量成正比,因此富磷的过渡金属磷化物最具吸引力。但目前富磷MP_x的合成比较困难,往往需要特殊的合成条  相似文献   

5.
于鹏  李景虹 《应用化学》2018,35(9):1093-1101
电化学分解水(Water Splitting)是获得高纯度氢能的重要手段。 因此,开发具有高活性低成本的电化学析氢反应(Hydrogen Evolution Reaction,HER)催化剂成为目前能源环境的研究热点之一。 本文总结了常用于HER反应的过渡金属硫化物以及磷化物非贵金属催化剂材料的合成方法,并且概况了如何构建特殊结构的金属硫化物及磷化物材料以调高材料的HER催化反应性能的方法,为开发其它高活性的非贵金属催化剂提供依据。  相似文献   

6.
对化石能源的依赖所造成的环境污染和能源危机在全球引起了广泛的关注.氢能由于其高能量密度、低分子质量以及清洁无污染的优点,被认为是人类根本性解决能源与环境等全球性问题的理想替代能源.电解水是生产高纯度氢的重要方法,是现代清洁能源技术的重要组成部分.水电解由阴极析氢(HER)和阳极析氧(OER)两个半反应构成.对于HER反应,其反应是基于二电子转移过程,反应过程相对容易进行.相比于HER反应,OER反应涉及四电子转移及氧-氧键形成,其反应动力学缓慢,是影响水电解效率的主要原因.因此,为了提高电解水制氢的能量转化效率,发展OER电催化剂成为水电解制氢技术的关键.在过去的十余年间,硫化物、硒化物、磷化物、硼化物等非贵金属基OER电催化剂被大量地研究及报道并取得了长足发展.在这些催化剂中,金属磷化物和硫化物不仅具有成本优势,而且在析氧过电位、耐久性方面正趋接近甚至超越RuO_2和IrO_2等贵金属催化剂,颇具应用潜力.本文总结磷化物和硫化物作为OER电催化剂的研究进展,重点介绍了磷化物和硫化物性能提升策略及其在OER过程中催化反应活性位的变化.本文首先介绍了电解水析氧反应在不同电解质中的反应机理,讨论了析氧反应在动力学和热力学过程的主要障碍.通过对大量文献的归纳,本文分别综述了磷化物和硫化物的化学性质、合成方法和催化性能,介绍了近年来磷化物和硫化物的重要研究进展.通过分析催化剂导电性、质子传输、活性面积、界面化学等因素对催化析氧反应的影响,总结了磷化物和硫化物电催化OER性能提升的策略.由于磷化物和硫化物在OER强氧化条件下,电催化剂表面的成分、物相及结构均会发生显著变化,进而催化反应活性位也会发生相应改变.本文综述了磷化物和硫化物在OER反应过程前后表面组分的变化,探讨了磷化物和硫化物作为OER电催化剂的活性组分,为进一步提高磷化物和硫化物的电催化析氧反应性能提供了崭新的思路.  相似文献   

7.
海水作为地球上最丰富的自然资源之一,在实现大规模的电解水制氢方面具有得天独厚的优势。然而,海水中的Cl-、Ca2+和Mg2+等使催化剂在阴极发生腐蚀、毒化或降解,导致其稳定性、活性以及使用寿命显著降低。近年来,为了解决上述问题,人们致力于设计开发廉价的高效稳定析氢反应(HER)催化剂,进而提高电解海水制氢效率。本文首先介绍了电解海水的优势及其HER所面临的挑战,其次从活性和稳定性等方面重点论述了硒化物、硫化物、氮化物以及磷化物等过渡金属基催化剂在电解海水HER中的研究进展,最后总结和展望了电解海水HER催化剂未来的发展前景。  相似文献   

8.
研究廉价且高效的水分解电催化剂对于氢能源的开发利用具有重要意义,过渡金属磷化物是最有前景的水分解双功能电催化剂之一。本研究采用先水热法,再低温磷化的简单的两步合成法,在三维镍网上生长CoP纳米珠链阵列,所生成的镍网(Nickel foam,NF)负载CoP纳米珠线阵列(CoP/NF),具有规则的形貌、较大的比表面积,在碱性条件下对氢气析出反应(HER)和氧气析出反应(OER)都表现出良好的电催化性能。在电流密度达到10 mA/cm~2时的过电位分别为280 mV(OER)及95 mV(HER)。利用此CoP/NF复合材料组成的双电极体系可以有效电解水,在电流密度为10 mA/cm~2时所需的施加电压仅为1.63 V,并且表现出非常高的稳定性。  相似文献   

9.
为了研发高效、稳定的电解水催化剂,我们以氧空位和磷掺杂为基础,通过原位浸泡生长和两步热处理的方法,在泡沫铁上合成具有氧空位和磷掺杂的纳米花结构作为析氢反应(HER)和析氧反应(OER)双功能电催化剂。CoFe2O4已被报道为一种很有前途的OER和氧还原反应(ORR)电催化剂,然而CoFe2O4在HER中表现出电导率差、电催化反应慢的特性。CoFe2O4中氧空位(Ov)的形成可以有效调控催化剂表面的电子结构,有助于产生更多的缺陷和空位,从而提高OER的活性。随后,引入磷原子填充在空位中,制备的P-Ov-CoFe2O4/IF在碱性电催化测试中展现出优异的HER和OER性能,在10 mA·cm-2电流密度下HER和OER过电位仅为54和191 mV,Tafel斜率分别为57和54 mV·dec-1,并具有良好的循环稳定性。  相似文献   

10.
电解水制氢技术碳排放量低、能量利用率高、所得氢气纯度高,在多数制氢技术中具有显著优势,业已成为学术界和工业界的研究热点。其中,电催化析氢反应(HER)处于核心地位,常涉及多步氢转移过程和多个活性位点共同参与的情况。然而,这些活性位点之间的催化关联和潜在的氢溢流效应常被忽视。本文回顾了过渡金属氧化物、磷化物和硫化物等的电催化体系的析氢性能和反应机制;结合传统热催化理论,将参与氢溢流的活性位点抽象总结为初级和次级活性位点,并明晰了它们的催化关联和功能差异;本文将不仅为高效廉价析氢电催化剂的创制提供一种设计理念,也为进一步研究涉氢电催化反应中的氢转移行为提供参考。  相似文献   

11.
For electrocatalysts for the hydrogen evolution reaction (HER), encapsulating transition metal phosphides (TMPs) into nitrogen-doped carbon materials has been known as an effective strategy to elevate the activity and stability. Yet still, it remains unclear how the TMPs work synergistically with the N-doped support, and which N configuration (pyridinic N, pyrrolic N, or graphitic N) contributes predominantly to the synergy. Here we present a HER electrocatalyst (denoted as MoP@NCHSs) comprising MoP nanoparticles encapsulated in N-doped carbon hollow spheres, which displays excellent activity and stability for HER in alkaline media. Results of experimental investigations and theoretical calculations indicate that the synergy between MoP and the pyridinic N can most effectively promote the HER in alkaline media.  相似文献   

12.
For electrocatalysts for the hydrogen evolution reaction (HER), encapsulating transition metal phosphides (TMPs) into nitrogen‐doped carbon materials has been known as an effective strategy to elevate the activity and stability. Yet still, it remains unclear how the TMPs work synergistically with the N‐doped support, and which N configuration (pyridinic N, pyrrolic N, or graphitic N) contributes predominantly to the synergy. Here we present a HER electrocatalyst (denoted as MoP@NCHSs) comprising MoP nanoparticles encapsulated in N‐doped carbon hollow spheres, which displays excellent activity and stability for HER in alkaline media. Results of experimental investigations and theoretical calculations indicate that the synergy between MoP and the pyridinic N can most effectively promote the HER in alkaline media.  相似文献   

13.
Even though transition-metal phosphides (TMPs) have been developed as promising alternatives to Pt catalyst for the hydrogen evolution reaction (HER), further improvement of their performance requires fine regulation of the TMP sites related to their specific electronic structure. Herein, for the first time, boron (B)-modulated electrocatalytic characteristics in CoP anchored on the carbon nanotubes (B-CoP/CNT) with impressive HER activities over a wide pH range are reported. The HER performance surpasses commercial Pt/C in both neutral and alkaline media at large current density (>100 mA cm−2). A combined experimental and theoretical study identified that the B dopant could reform the local electronic configuration and atomic arrangement of bonded Co and adjacent P atoms, enhance the electrons’ delocalization capacity of Co atoms for high electrical conductivity, and optimize the free energy of H adsorption and H2 desorption on the active sites for better HER kinetics.  相似文献   

14.
Even though transition‐metal phosphides (TMPs) have been developed as promising alternatives to Pt catalyst for the hydrogen evolution reaction (HER), further improvement of their performance requires fine regulation of the TMP sites related to their specific electronic structure. Herein, for the first time, boron (B)‐modulated electrocatalytic characteristics in CoP anchored on the carbon nanotubes (B‐CoP/CNT) with impressive HER activities over a wide pH range are reported. The HER performance surpasses commercial Pt/C in both neutral and alkaline media at large current density (>100 mA cm?2). A combined experimental and theoretical study identified that the B dopant could reform the local electronic configuration and atomic arrangement of bonded Co and adjacent P atoms, enhance the electrons’ delocalization capacity of Co atoms for high electrical conductivity, and optimize the free energy of H adsorption and H2 desorption on the active sites for better HER kinetics.  相似文献   

15.
《中国化学快报》2023,34(9):108156-51
Hydrogen evolution from water electrolysis has become an important reaction for the green energy revolution. Traditional precious metals and their compounds are excellent catalysts for producing hydrogen; however, their high cost limits their large-scale practical application. Therefore, the development of affordable electrocatalysts to replace these precious metals is important. Transition metal phosphides(TMPs) have shown remarkable performance for hydrogen evolution and garnered considerable ...  相似文献   

16.
《中国化学快报》2022,33(8):3987-3992
Green hydrogen production and CO2 fixation have been identified as the fundamental techniques for sustainable economy. The open challenge is to develop high performance catalysts for hydrogen evolution reaction (HER) and CO2 electroreduction (CO2ER) to valuable chemicals. Under such context, this work reported computational efforts to design promising electrocatalyst for HER and CO2ER based on the swarm-intelligence algorithm. Among the family of transition-metal phosphides (TMPs), Pt2P3 monolayer has been identified as excellent bifunctional catalysts due to high stability, excellent conductivity and superior catalytic performance. Different from typical d-block catalysts, p-band center presented by P atoms within Pt2P3 monolayer plays the essential role for its reactivity towards HER and CO2ER, underlining the key value of p-electrons in advanced catalyst design and thus providing a promising strategy to further develop novel catalysts made of p-block elements for various energy applications.  相似文献   

17.
Transition‐metal phosphides (TMPs) have emerged as promising catalyst candidates for the hydrogen evolution reaction (HER). Although numerous methods have been investigated to obtain TMPs, most rely on traditional synthetic methods that produce materials that are inherently deficient with respect to electrical conductivity. An electrospinning‐based reduction approach is presented, which generates nickel phosphide nanoparticles in N‐doped porous carbon nanofibers (Ni2P@NPCNFs) in situ. Ni2P nanoparticles are protected from irreversible fusion and aggregation in subsequent high‐temperature pyrolysis. The resistivity of Ni2P@NPCNFs (5.34 Ω cm) is greatly decreased by 104 times compared to Ni2P (>104 Ω cm) because N‐doped carbon NFs are incorporated. As an electrocatalyst for HER, Ni2P@NPCNFs reveal remarkable performance compared to other previously reported catalysts in acidic media. Additionally, it offers excellent catalytic ability and durability in both neutral and basic media. Encouraged by the excellent electrocatalytic performance of Ni2P@NPCNFs, a series of pea‐like MxP@NPCNFs, including Fe2P@NPCNFs, Co2P@NPCNFs, and Cu3P@NPCNFs, were synthesized by the same method. Detailed characterization suggests that the newly developed method could render combinations of ultrafine metal phosphides with porous carbon accessible; thereby, extending opportunities in electrocatalytic applications.  相似文献   

18.
Research on Chemical Intermediates - Transition-metal phosphides (TMPs) have emerged as anode materials for lithium-ion batteries owing to their high theoretical capacity and stable cyclability....  相似文献   

19.
Transition-metal-based phosphides (TMPs) have been considered as attractive electrocatalysts for water splitting due to their earth-abundance and remarkable catalytic activity. As a representative type of precursors, metal-organic frameworks (MOFs) provide ideal plateaus for the design of nanostructured TMPs. In this work, the hierarchically structured iron phosphide nanobundles (FeP-500) were fabricated by one-step phosphorization of an iron-based MOF (MET(Fe)) precursor. The derived FeP-500 nanobundles were constructed by quasi-paralleled one-dimensional nanorods with uneven surface, which provided channels for electrolyte penetration, mass transport, and effective exposure of active sites during the water-splitting process. With the addition of conductive Super P, the obtained FeP-500-S exhibited a good electrocatalytic performance towards the hydrogen evolution reaction in alkaline electrolyte (1 mol L−1 KOH). Furthermore, to investigate the influence of secondary metal doping, a series of isoreticular MOF precursors and bimetallic TMPs were fabricated. The results indicated that the catalytic performance is structure dominated.  相似文献   

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