铁镍合金纳米颗粒镶嵌的多级孔氮掺杂碳催化剂的制备及析氧性能研究

非贵金属铁镍合金催化剂在析氧反应（OER）中性能优异，表现出取代贵金属RuO₂催化剂的巨大潜力.以SiO₂为大孔模板，多巴胺为氮碳源，Fe³⁺，Ni²⁺为金属源，通过原位吸附、聚合、焙烧、刻蚀等步骤制备得到铁镍合金纳米颗粒镶嵌的多级孔氮掺杂碳催化剂.碱性介质中的析氧反应测试表明，合金催化剂达到电流密度10 mA·cm^-2时过电位仅为286 mV，显著低于以RuO₂为催化剂的380 mV过电位；同时经过2000圈循环伏安老化后活性几乎无衰减，稳定性高.所制备的合金催化剂具有两方面结构优势：（1）铁镍合金以及单质铁纳米颗粒镶嵌于大孔碳的薄层孔壁中，有利于暴露活性位点；（2）石墨化氮碳层对合金纳米颗粒的保护提高了材料抗腐蚀性，进而提升其稳定性.     

二硫化钼纳米片/碳纳米纤维杂化材料的制备及其析氢性能

以碳纳米纤维(CNFs)作为负载基体和反应器采用静电纺丝技术和碳化工艺生长和调控二硫化钼(MoS_2)纳米片。通过改变前驱体溶液浓度来调控纳米片的形貌和结构,利用MoS_2纳米片的高催化活性和CNFs高比表面积、良好的稳定性以及高电导率的协同作用,研究不同形貌和结构的杂化纳米材料在电催化析氢方面的应用,探索杂化材料形貌与性能之间的潜在规律。运用多种分析测试技术对制备得到的纳米杂化材料进行表征,并对所制备的MoS_2/CNFs杂化材料的电催化析氢性能(HER)进行研究,研究表明近似皮芯结构的MoS_2/CNFs-10杂化材料的电催化析氢性能最好,初始析氢过电位在220 mV,Tafel斜率为110m V·dec~(-1)。     

二硫化钼纳米片/碳纳米纤维杂化材料的制备及其析氢性能

以碳纳米纤维（CNFs）作为负载基体和反应器采用静电纺丝技术和碳化工艺生长和调控二硫化钼（MoS₂）纳米片。通过改变前驱体溶液浓度来调控纳米片的形貌和结构,利用MoS₂纳米片的高催化活性和CNFs高比表面积、良好的稳定性以及高电导率的协同作用,研究不同形貌和结构的杂化纳米材料在电催化析氢方面的应用,探索杂化材料形貌与性能之间的潜在规律。运用多种分析测试技术对制备得到的纳米杂化材料进行表征,并对所制备的MoS₂/CNFs杂化材料的电催化析氢性能（HER）进行研究,研究表明近似皮芯结构的MoS₂/CNFs-10杂化材料的电催化析氢性能最好,初始析氢过电位在220 mV,Tafel斜率为110 mV·dec^-1。     

Ru-Ni/C催化剂在碱性介质中的析氢性能研究

氢气的高效生产和利用对构建清洁低碳的能源体系至关重要, 碱性电解水制氢是目前我国应用最多的制氢技术,但也存在能耗较高的难题。因此迫切需要寻找低成本、高性能的电催化剂用于析氢反应（HER）提高水分解效率。本工作采用沉积沉淀法合成了双金属负载型Ru-Ni/C催化剂,用透射电子显微镜（TEM）和X射线衍射（XRD）对催化剂的形貌和结构进行了表征。用线性扫描伏安法（LSV）、电化学阻抗谱（EIS）等测试了HER性能。结果显示炭载体上RuNi双金属均匀分散,在电流密度为10 mA?cm-2时过电位仅为34.4 mV且稳定性良好,Tafel斜率仅为60.33 mV?dec-1,比商用Pt/C还小。表明Ru-Ni/C催化剂展现出了优异的HER电催化活性和稳定性,RuNi双金属之间的协同效应很大程度上促进了催化剂的催化性能,该研究为发展高效的碱性电解水制氢阴极催化剂提供了新思路。     

球形碳掺杂钴基催化剂用于HER和锌空电池阴极反应

电催化水裂解是一种制备清洁氢气的潜在方法,寻找一种催化剂提高电催化阴极析氢反应(HER)速率是研究热点。通过制备球形碳掺杂钴基催化剂并对其进行硫化或磷化处理以提高其催化性能。三种产物中,CoP/C催化性能最优。在酸性和碱性条件下,电流密度为10 mA·cm^-2时的析氢过电位分别为154 mV和89 mV,并且稳定性优良。该催化剂被进一步用作空气阴极,以构建用于能量转换的锌-空气电池。该电池的开路电压为1.35 V,维持50 h没有衰减,并且通过27 h的长期循环试验评估了其可充电性,电压间隙为1.2 V。这项工作为设计球形非贵金属多组分HER催化剂提供了新的策略。     

基于纳米银/碳纳米纤维复合材料的增强效应电化学测定多贝斯

将银纳米粒子(AgNPs)电沉积在碳纳米纤维(CNFs)修饰玻碳电极表面制备纳米银/碳纳米纤维修饰玻碳电极(AgNPs/CNFs/GCE).采用扫描电镜考察其表面形态,在K3[Fe(CN)6]-K4[Fe(CN)6]体系中用循环伏安法和电化学阻抗法研究AgNPs/CNFs/GCE的电化学行为.采用循环伏安法和方波伏安法...     

纳米非晶镍硼合金的合成及其碱性电催化析氢性能研究（英文）

可持续能源电解水制氢是实现零碳排放氢经济的有效途径。碱性环境下的电催化析氢反应(HER)是电解水技术主要的能量转换过程之一。开发高活性、低成本的非贵金属催化剂是碱性电解水析氢反应的关键所在。本研究以壳寡糖为保护剂,采用简单易行的化学还原法制备了纳米NiB非晶合金电催化剂并用于碱性析氢反应。采用X射线衍射(XRD)、透射电子显微镜(TEM)、电感耦合等离子体分析(ICP)和X射线光电子能谱(XPS)等多种表征方法研究了不同条件下获得的催化剂结构组成及特征物性参数。结果表明,壳寡糖的加入可以有效调控纳米粒子的平均粒径为4 nm左右,提升活性比表面积,增加活性位点,从而提高其电催化活性。所制备的NiB-COS在1.0 mol/L NaOH中表现出优异的HER性能,析氢反应起始过电位仅为15.1 mV,在电流密度为10 mA/cm²时HER过电位为49.4 mV,Tafel斜率为86.1 mV/dec,为制备高活性、低成本、简单易得的HER电催化剂提供了重要策略。     

Cu/La2O3 催化裂解乙炔制备碳纳米纤维

用沉淀法制备了Cu/La2O3催化剂,将其用于催化裂解乙炔制备了碳纳米纤维(CNFs).考察了反应温度和反应时间对CNFs产率的影响.用SEM和微机差热天平分别对CNFs的形貌和抗氧化性能进行了研究.实验结果表明:于650 ℃反应3 h, CNFs产率为1.4 g·(g Cat.)-1;CNFs形态规则,表面光滑,直径300 nm～700 nm,长度达几十微米;CNFs燃烧温度515 ℃～544 ℃.     

非晶态NiP基催化剂的制备及电催化析氢性能研究

以NaH₂PO₂和Ni₂SO₄为磷源和镍源,使用一锅法合成了非晶态NiP合金及其碳纳米（乙炔黑和石墨烯）复合催化剂。用透射电子显微镜（TEM）、X射线衍射仪（XRD）、热重分析（TGA）、电感耦合等离子体光谱仪（ICP）分别对催化剂性能和组成进行了表征和分析。通过线性扫描伏安对催化剂在酸性和碱性条件下的析氢性能进行了评价,研究结果表明,非晶态NiP/还原氧化石墨烯复合催化剂（NiP/RGO）展现出优异的电催化性能。在0.5 mol/L H₂SO₄中的起始过电位为89.0 mV,塔菲尔斜率为135.1 mV/decade;在1 mol/L NaOH中,起始过电位为116.1 mV,塔菲尔斜率为122.4 mV/decade,这与商业化Pt黑催化剂很接近。500次循环以后,催化剂活性没有明显下降,表明该催化剂具有良好的稳定性。该研究提供了一种简单可行的制备非贵金属磷化物方法用于电催化析氢反应。     

基于纳米氧化钴/碳纳米纤维复合材料的增强效应电化学测定对乙酰氨基酚

建立了电化学测定片剂中对乙酰氨基酚含量的新方法。通过电沉积的方法在碳纳米纤维修饰玻碳电极(CNFs/GCE)表面上沉积纳米氧化钴(CoO_x),制备了纳米CoO_x/碳纳米纤维修饰玻碳电极(CoO_x/CNFs/GCE)。在pH 5.33的B–R缓冲溶液中,用循环伏安法研究了对乙酰氨基酚在CoO_x/CNFs/GCE和CNFs/GCE上的电化学行为。结果表明,二者对对乙酰氨基酚的氧化还原反应都有电催化作用,而且复合纳米材料CoO_x/CNFs具有较单一CNFs更好的催化效果。用微分脉冲伏安法测得对乙酰氨基酚的氧化峰电流与其浓度在3.0×10~(-7)~1.5×10~(–4) mol/L范围内呈线性关系,检出限为1.0×10~(-7) mol/L(S/N=3)。测定结果的相对标准偏差为2.31%(n=6),加标回收率为96.0%~105.0%。该方法简便快速,检出限低,准确度和精密度高,适用于片剂中对乙酰氨基酚含量的测定。     

Acicular Nickel on Carbon Nanofiber as Electrochemical Sensor Electrode for the Rapid Detection of Aqueous and Gaseous Formaldehyde at Room Temperature

The rapid and straightforward detection of formaldehyde (FA) in the environment is crucial for preventing the accidental inhalation of FA and limiting skin exposure to FA. In this study, we developed a simple nickel-based electrocatalytic electrode on carbon nanofibers (CNFs−Ni), which is suitable for rapidly detecting FA at room temperature. Centrifugal electrospinning was used to obtain polyacrylonitrile (PAN) nanofibers, which was subsequently stabilized and carbonized to fabricate the CNFs. Carbonization of the CNFs occurred at various temperatures (T_c=1200, 1300, 1400, and 1500 °C). PAN CNFs served as a highly conductive template for electroless plating under a magnetic field of 500 G to grow acicular nickel. The amperometric responses of the CNFs−Ni to aqueous FA were then measured. A lab-built amperometric gas sensor (CNFs−Ni 1–8), which comprised CNFs with a reduced Ni loading, was used as the electrode for detecting gaseous FA. Scanning electron microscopy (SEM), linear sweep voltammetry (LSV), cyclic voltammetry (CV), and chronoamperometry were used to evaluate the sensitivities of the electrodes. Within the linear range of 0.05–91.5 mM, the CNFs1400-Ni electrode was highly sensitive for detecting aqueous FA (2592 μA mM⁻¹ cm⁻²), as evidenced by the fast response time (6 s). At a low concentration of gaseous FA (0.5 ppm), the laboratory-built FA gas sensor was stable (98.3 %) and had a fast response time (5 s) after 9 h of continuous operation.     

Amorphous Co-P Film: an Efficient Electrocatalyst for Hydrogen Evolution Reaction in Alkaline Seawater

Seawater electrolysis is considered an attractive alternative to conventional freshwater electrolysis for hydrogen production due to the abundance of seawater in nature. For this reason, efficient electrocatalysts for hydrogen evolution reaction (HER) in alkaline seawater are highly desired. In this study, we report an amorphous Co−P alloy on nickel foam (Co−P/NF) that behaves as an efficient and stable HER electrocatalyst for alkaline seawater electrolysis. The Co−P/NF presents high catalytic performance for HER, requiring a low overpotential of 213 mV to drive a current density of 100 mA cm⁻² and a Tafel slope of 120.2 mV dec⁻¹ in alkaline seawater. Furthermore, it shows remarkable electrochemical and structural stability in alkaline seawater.     

Carbon Nanotubes Decorated with CoP Nanocrystals: A Highly Active Non‐Noble‐Metal Nanohybrid Electrocatalyst for Hydrogen Evolution

The development of effective and inexpensive hydrogen evolution reaction (HER) electrocatalysts for future renewable energy systems is highly desired. The strongly acidic conditions in proton exchange membranes create a need for acid‐stable HER catalysts. A nanohybrid that consists of carbon nanotubes decorated with CoP nanocrystals (CoP/CNT) was prepared by the low‐temperature phosphidation of a Co₃O₄/CNT precursor. As a novel non‐noble‐metal HER catalyst operating in acidic electrolytes, the nanohybrid exhibits an onset overpotential of as low as 40 mV, a Tafel slope of 54 mV dec^?1, an exchange current density of 0.13 mA cm^?2, and a Faradaic efficiency of nearly 100 %. This catalyst maintains its catalytic activity for at least 18 hours and only requires overpotentials of 70 and 122 mV to attain current densities of 2 and 10 mA cm^?2, respectively.     

Enhancing Hydrogen Evolution by Optimizing the Hydrogen Adsorption on Titanium Monoxide Nanodot-Decorated Cobalt Sulfide Nanosheets

Modulating the local electronic state of metal compounds through interfacial interaction has become a key method for manufacturing high-performance hydrogen evolution reaction (HER) electrocatalysts. The electron-rich active sites can promote the adsorption of hydrogen, which accelerates the Volmer step and thereby enhances the electrocatalytic performance of HER. Here, we found that the strong interfacial interaction between TiO nanodots (TiO/Co−S) and Co−S nanosheets could advantageously improve the performance toward HER of electrocatalyst. Meanwhile, XPS results showed that modulating the local electronic structure of the TiO nanodots produces electron-rich regions on Co. As a result, the overpotential of the TiO/Co−S nanocomposite at 10 mA cm⁻² was 107 mV, and the Tafel slope was 83.3 mV dec⁻¹. This study focused on the effect of the solid-solid interface on the local electronic structure of the catalytic metal active sites and successfully improved the catalytic activity of transition metal materials in HER catalysis.     

Ni2P Interlayer and Mn Doping Synergistically Expedite the Hydrogen Evolution Reaction Kinetics of Co2P

Transition metal phosphide is regarded as one of the most promising candidates to replace noble-metal hydrogen evolution reaction (HER) electrocatalysts. Nevertheless, the controllable design and synthesis of transition metal phosphide electrocatalysts with efficient and stable electrochemical performance are still very challenging. Herein, a novel hierarchical HER electrocatalyst consisting of three-dimensional (3D) coral-like Mn-doped Co₂P@an intermediate layer of Ni₂P generated in situ by phosphorization on Ni foam (MnCoP/NiP/NF) is reported. Notably, both the incorporation of Mn and introduction of the Ni₂P interlayer promote Co atoms to carry more electrons, which is beneficial to reduce the force of the Co−H bond and optimize the adsorption energy of hydrogen intermediate (|ΔG_H*|), thereby making MnCoP/NiP/NF exhibit outstanding HER performance with onset overpotential and Tafel slope as low as 31.2 mV and 61 mV dec⁻¹, respectively, in 1 m KOH electrolyte.     

Electron-transfer enhanced MoO2-Ni heterostructures as a highly efficient pH-universal catalyst for hydrogen evolution

Hydrogen is one of the most promising energy carriers to replace fossil fuels and electrolyzing water to produce hydrogen is a very effective method. However, designing highly active and stable non-precious metal hydrogen evolution electrocatalysts that can be used in universal pH is a huge challenge. Here, we have reported a simple strategy to develop a highly active and durable non-precious MoO_2-Ni electrocatalyst for hydrogen evolution reaction(HER) in a wide pH range. The MoO_2-Ni catalyst exhibits a superior electrocatalytic performance with low overpotentials of 46, 69, and 84 mV to reach-10 mA cm~(-2) in 1.0 M KOH, 0.5 M H_2SO_4,and 1.0 M PBS electrolytes, respectively. At the same time, the catalyst also shows outstanding stability over a wide pH range. It is particularly noted that the catalytic performance of MoO_2-Ni in alkaline solution is comparable to the highest performing catalysts reported. The outstanding HER performance is mainly attributed to the collective effect of the rational morphological design, electronic structure engineering, and strong interfacial coupling between MoO_2 and Ni in heterojunctions.This work provides a viable method for the synthesis of inexpensive and efficient HER electrocatalysts for the use in wide pH ranges.     

Devisable POM/Ni Foam Composite: Precisely Control Synthesis toward Enhanced Hydrogen Evolution Reaction at High pH

Polyoxometalates (POMs) are promising catalysts for the electrochemical hydrogen production from water owing to their high intrinsic catalytic activity and chemical tunability. However, poor electrical conductivity and easy detachment of the POMs from the electrode cause significant challenges under operating condition. Herein, a simple one-step hydrothermal method is reported to synthesize a series of Dexter–Silverton POM/Ni foam composites (denoted as Ni M -POM/Ni; M =Co, Zn, Mn), in which the stable linkage between the POM catalysts and the Ni foam electrodes lead to high activity for the hydrogen evolution reaction (HER). Among them, the highest HER performance can be observed in the NiCo-POM/Ni, featuring an overpotential of 64 mV (at 10 mA cm⁻², vs. reversible hydrogen electrode), and a Tafel slope of 75 mV dec⁻¹ in 1.0 m aqueous KOH. Moreover, the NiCo-POM/Ni catalyst showed a high faradaic efficiency ≈97 % for HER. Post-catalytic of NiCo-POM/Ni analyses showed virtually no mechanical or chemical degradation. The findings propose a facile and inexpensive method to design stable and effective POM-based catalysts for HER in alkaline water electrolysis.     

Development of nano IrO<Subscript>2</Subscript> composite-reinforced nickel–phosphorous electrodes for hydrogen evolution reaction

Electroless and electroplated nickel electrodes are extensively used for hydrogen evolution reaction (HER). In the present work, TiO₂-supported IrO₂ mixed oxide composite was prepared and used to reinforce Ni–P electroless plates to be used as catalytic electrodes for HER. The electrodes exhibited high electrocatalytic activity when the electrodes were used for HER. All the parameters including particle size of the catalyst, surface roughness, and surface active sites were studied. The particle size of the IrO₂ catalyst in the mixed oxide was found to have high influence on the catalytic activity of the electrodes. Low overpotential as low as 70 mV at a current density of 200 mA cm⁻² was achieved with the mixed oxide-reinforced Ni–P electrodes.