Catalyst Enhanced Chemical Vapor Depositionof Nickel on Polymer Surface

Catalyst enhanced chemical vapor deposition of nickel film on high Tg polymers such as teflon(PTFE), polyimide(PI), and polysulfone(PS) was investigated by hot wall and cold wall CVD, in which Ni(dmg)_2, Ni(acac)_2, Ni(hfac)_2, Ni(TMHD)_2, and Ni(cp)_2 are used as precursors, and palladium complexes are used as catalysts. The films obtained were shiny with silvery color. The Ni was metallic and the purity of Ni was about 92%-95% from XPS analysis. SEM micrographs show that the film had good morphology. The conductivity of the film was about 0.5-4 W·cm^(-1). Ni films had good adhesion with polyimide and polysulfone.

Electrochemically switched ion exchange performances of capillary deposited nickel hexacyanoferrate thin films

Thin films of capillary deposited nickel hexacyanoferrate(NiHCF) were investigated as electrochemically switched ion exchange(ESIX) materials. The films were generated on platinum and graphite substrates based on the ternary reagent diagram. In 1 mol/L KNO3 solution, cyclic voltammetry(CV) combined with energy-dispersive X-ray spectroscopy(EDS) was used to determine the influence of experimental conditions on the electroactivity of the NiHCF thin film on Pt substrates. The ion selectivity, ion-exchange capacity and the regenerability of NiHCF films on Pt and graphite substrates were investigated. The experiment results show that the NiHCF thin films from Ni2+-poor growth conditions have double peaks CV curves and contain relatively larger amount of potassium; while those from Ni2+-rich growth conditions are single peak CV curves and contain relatively smaller amount of potassium. It is demonstrated that the NiHCF thin films of capillary chemical deposition have good ESIX performances.

Engineering of Self-Supported Electrocatalysts on a Three-Dimensional Nickel Foam Platform for Efficient Water Electrolysis

Economical water electrolysis requires highly active non-noble electrocatalysts to overcome the sluggish kinetics of the two half-cell reactions,oxygen evolution reaction,and hydrogen evolution reaction.Although intensive efforts have been committed to achieve a hydrogen economy,the expensive noble metal-based catalysts remain under consideration.Therefore,the engineering of self-supported electrocatalysts prepared using a direct growth strategy on three-dimensional(3D)nickel foam(NF)as a conductive substrate has garnered significant interest.This is due to the large active surface area and 3D porous network offered by these electrocatalysts,which can enhance the synergistic eff ect between the catalyst and the substrate,as well as improve electrocatalytic performance.Hydrothermal-assisted growth,microwave heating,electrodeposition,and other physical methods(i.e.,chemical vapor deposition and plasma treatment)have been applied to NF to fabricate competitive electrocatalysts with low overpotential and high stability.In this review,recent advancements in the development of self-supported electrocatalysts on 3D NF are described.Finally,we provide future perspectives of self-supported electrode platforms in electrochemical water splitting.

Enhancement of nucleation of diamond films deposited on copper substrate by nickel modification layer

A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibrium shape was deposited on Cu substrates by hot-filament chemical vapor deposition（HF-CVD）,and the sp2 carbon content was less than 5.56%.The nucleation and growth of diamond film were investigated by micro-Raman spectroscopy,scanning electron microscopy,and X-ray diffraction.The results show that the nucleation density of diamond on the Ni-modified Cu substrates is 10 times higher than that on blank Cu substrates.The enhancement mechanism of the nucleation kinetics by Ni modification layer results from two effects：namely,the nanometer rough Ni-modified surface shows an improved absorption of nanodiamond particles that act as starting points for the diamond nucleation during HF-CVD process;the strong catalytic effect of the Ni-modified surface causes the formation of graphite layer that acts as an intermediate to facilitate diamond nucleation quickly.

Catalyst Enhanced Chemical Vapor Deposition of Nano-Particle Nickel Films on Teflon Surface

Films formed with nanosized nickel particles on teflon surface were prepared by means of catalyst enhanced chemical vapor deposition （CECVD） with Ni（dmg）2, Ni（acac）2, Ni（hfac）2, Ni（TMHD）2, and Ni（cp）2 as precursors, and complexes Pd（hfac）2, PdC12 and Pd（η^3-2-methylallyl）acac as catalyst under cartier gas （H2）. The film growth rate depends on the precursors and substrate temperature. The chemical value, purity and surface morphology of the Ni particle films were characterized by X-ray photoelectron spectroscopy （XPS） and scanning electron microscopy （SEM）. The films obtained were shiny with silvery color, and consisted of grains with a particle size of 50-140 nm. The Ni was metallic of which the purity was about 90%-95% from XPS analysis. SEM micrograph showed that the film had good morphology.

Nickel oxide thin films grown by chemical deposition techniques: Potential and challenges in next-generation rigid and flexible device applications

Nickel oxide(NiOx),a p-type oxide semiconductor,has gained significant attention due to its versatile and tunable properties.It has become one of the critical materials in wide range of electronics applications,including resistive switching random access memory devices and highly sensitive and selective sensor applications.In addition,the wide band gap and high work function,coupled with the low electron affinity,have made NiOx widely used in emerging optoelectronics and p-n heterojunctions.The properties of NiOx thin films depend strongly on the deposition method and conditions.Efficient implementation of NiOx in next-generation devices will require controllable growth and processing methods that can tailor the morphological and electronic properties of the material,but which are also compatible with flexible substrates.In this review,we link together the fundamental properties of NiOx with the chemical processing methods that have been developed to grow the material as thin films,and with its application in electronic devices.We focus solely on thin films,rather than NiOx incorporated with one-dimensional or two-dimensional materials.This review starts by discussing how the p-type nature of NiOx arises and how its stoichiometry affects its electronic and magnetic properties.We discuss the chemical deposition techniques for growing NiOx thin films,including chemical vapor deposition,atomic layer deposition,and a selection of solution processing approaches,and present examples of recent progress made in the implementation of NiOx thin films in devices,both on rigid and flexible substrates.Furthermore,we discuss the remaining challenges and limitations in the deposition of device-quality NiOx thin films with chemical growth methods.

Laser-induced voltage effects in Ca_3Co_4O_9 thin films on tilted LaAlO_3(001) substrates grown by chemical solution deposition

Laser-induced voltage effects in c-axis oriented Ca3Co4O9 thin films have been studied with samples fabricated on 10°tilted LaAIO3 （001） substrates by a simple chemical solution deposition method. An open-circuit voltage with a rise time of about 10 ns and full width at half maximum of about 28 ns is detected when the film surface is irradiated by a 308-nm laser pulse with a duration of 25 ns. Besides, opemcircuit voltage signals are also observed when the film surface is irradiated separately by the laser pulses of 532 nm and 1064 nm. The results indicate that Ca3Co4O9 thin films have a great potential application in the wide range photodetctor from the ultraviolet to near infrared regions.

Fabrication of micro carbon pillar by laser-induced chemical vapor deposition

Argon ion laser was used as the induced light source and ethane(C2H4) was selected as the precursor gas,in the variety ranges of laser power from 0.5 W to 4.5 W and the pressure of the precursor gas from 225×133.3 Pa to 680×133.3 Pa,the experiments of laser induced chemical vapor deposition were proceeded for fabrication of micro carbon pillar.In the experiments,the influences of power of laser and pressure of work gas on the diameter and length of micro carbon pillar were investigated,the variety on averaged growth rate of carbon pillar with the laser irradiation time and moving speed of focus was discussed.Based on experiment data,the micro carbon pillar with an aspect ratio of over 500 was built through the method of moving the focus.

In-situ monitored chemical bath deposition of planar NiO x layer for inverted perovskite solar cell with enhanced efficiency

As a convenient,low-cost and up-scalable solution route,chemical bath deposition(CBD)has exhibited impressive advantages in fabricating electron transporting materials like SnO_(2),achieving record efficien-cies for regular n-i-p perovskite solar cells(PSCs).However,for the hysteresis-free and potentially more stable inverted p-i-n PSCs,CBD processing is rarely studied to improve the device performance.In this work,we first present a CBD planar NiO x film as the efficient hole transport layer for the inverted per-ovskite solar cells(IPSCs).The morphologies and semiconducting properties of the NiO x film can be ad-justed by varying the concentration of[Ni(H 2 O)x(NH 3)6-x]2+cation via in-situ monitoring of the CBD re-action process.The characterizations of ultraviolet photoelectron spectroscopy,transient absorption spec-troscopy,time-resolved photoluminescence suggest that the CBD planar NiO x film possesses enhanced conductivity and aligned energy band levels with perovskite,which benefits for the charge transport in the IPSCs.The devices based on planar NiO x at 50°C and low nickel precursor concentration achieved an enhanced efficiency from 16.14%to 18.17%.This work established an efficient CBD route to fabricate planar NiO x film for PSCs and paved the way for high performance PSCs with CBD-prepared hole transporting materials.

Ni-Co-B-RE(Sm、Dy、Tb)复合电极:化学沉积法制备及电催化析氢性能研究

开发低成本、高活性的非贵金属电催化剂对电解水的实际应用具有重要意义,稀土(Rare Earth,RE)元素因其独特的电子结构成为金属催化剂改性的研究热点,但在泡沫镍(Nickel Foam,NF)基体上制备稀土复合催化剂的方法存在成本高、工艺复杂和耗时长等问题。本研究采用一步化学沉积法,在NF基体上制备了三种稀土复合电极Ni-Co-B-Tb/NF、Ni-Co-B-Sm/NF和Ni-Co-B-Dy/NF,对催化电极的结构和形貌进行了表征,并研究其在1 mol·L^(–1)KOH溶液中的析氢性能。结果表明,添加Sm、Dy和Tb可使电极的电子结构发生改变,改善催化剂材料的本征性质,进而提高析氢反应(Hydrogen Evolution Reaction,HER)的催化性能。其中,Ni-Co-B-Tb/NF表现出最佳的析氢性能,达到10 mA·cm^(–2)的电流密度仅需58 mV的过电位,Tafel斜率为65 mV·dec^(–1),析氢反应由Volmer-Heyrovsky步骤控制。进一步研究发现稀土浓度对电催化性能影响较大,当Tb浓度为3 g·L^(–1)时,Ni-Co-B-Tb/NF表面颗粒尺寸较小且分布均匀,暴露出更多的活性位点,有利于HER的电荷转移,析氢性能最佳。此外,经过100 h长期稳定性测试和2000次循环伏安(Cyclic Voltammetry,CV)测试后,该催化剂表现出良好的电化学稳定性。

电化学法处理碱性锌镍合金废水技术研究

碱性锌镍合金废水中含有多种电镀配位剂,与废水中的重金属形成较为稳定的配位络合形式,常用的废水处理方法难以将废水中的重金属去除至达标。为解决困扰锌镍合金企业的废水重金属达标处理的问题,采用电化学法处理碱性锌镍合金废水。研究了废水初始pH值、电流密度、极板间距等因素对锌镍合金废水处理效果的影响,并探索了电化学法与离子交换树脂组合工艺的处理效果。结果表明:经过电化学处理,废水中的锌和镍以电沉积方式在阴极表面析出,锌和镍的质量浓度得到大幅降低;电化学法出水锌和镍的去除率可分别达到84.2%和88.4%,再经离子交换树脂处理后锌和镍分别低于1.0 mg/L和0.1 mg/L,满足排放标准要求。

中粗化微蚀药水引起化学镀镍/金不良的探讨

中粗化微蚀药水可以增加铜面粗糙度,改善阻焊油墨等在铜面的附着力。但在使用中发现,某款中粗化微蚀药水后直接印刷阻焊油墨,存在化镍金沉积不良问题。通过讨论中粗化微蚀药水引起化镍金沉积不良问题的机理,并经过测试验证,确定了化镍金沉积不良问题的改善方案。

Controllable synthesis of NiS and NiS2 nanoplates by chemical vapor deposition

Mulitipe stoichiometric ratio of two-dimensional(2D)transition metal dichalcogenides(TMDCs)attracted considerable interest for their unique chemical and physical properties.Here we developed a chemical vapor deposition(CVD)method to controllably synthesize ultrathin NiS and NiS2 nanoplates.By tuning the growth temperature and the amounts of the sulfur powder,2D nonlayered NiS and NiS2 nanoplates can be selectively prepared with the thickness of 2.0 and 7.0 nm,respectively.X-ray diffraction(XRD)and transmission electron microscopy(TEM)characterization reveal that the 2D NiS and N1S2 nanoplates are high-quality single crystals in the hexagonal and cubic phase,respectively.Electrical transport studies show that electrical conductivities of the 2D NiS and N1S2 nanoplates are as high as 4.6 x 10^5 and 6.3 x 10^5 S·m^-1,respectively.The electrical results demonstrate that the synthesized metallic NiS and NiS2 could serve as good electrodes in 2D electronics.

Antiferromagnetism and p-type conductivity of nonstoichiometric nickel oxide thin films

Nickel oxide(NiO)is one of the most studied transition metal oxides due to its versatile chemical and electronic properties,enabling it to be used in a wide variety of applications.In its stoichiometric form,NiO is an antiferromagnetic insulator,with resistivity up to 10^13Ωcm.1 When Ni vacancies are introduced,the nonstoichiometric nickel oxide becomes a semiconductor.

GR@Ni复合电极的制备及电化学性能研究

采用非溶剂致相分离法(NIPS)、高温烧结和化学气相沉积法(CVD)相结合的方法制备了石墨烯/多孔镍复合电极(3DPNGNs),明确了烧结温度和C_(2)H_(2)气流量对电极性能的影响。镍膜生坯经850℃烧结后,C_(2)H_(2)气流量为2 mL/min时,催化生长出石墨烯能均匀包覆在多孔镍膜上。结果表明,3DPNGNs作为钠离子电池负极材料展现了良好的电化学性能,在100 mA/g的电流密度下,循环100次后可逆比容量可达260 mA/g,循环500次后,其比容量保持率仍可达84%。当电流密度增大到1 A/g时,循环500次,比容量可达150 mA/g。

Investigation on Quick Surface Metallization of Nano Titania Powder

Quick surface metallization of titania powder was carried out by electrolesschemical deposition of nickel. The fabricated product was characterized by XRD, SEM, FTIR andcross-section metallography. The analysis results show that titania particles are completely coatedby a thin nickel shell about 600 nm thick composed of nano-sized crystalline nickel particles.Mechanism of nickel chemical deposition on nano powder is proposed.

化学沉淀法回收化学镀镍废水中镍的研究

采用化学沉淀法从化学镀镍废水中回收镍,通过实验优化了NaOH处理含镍废水的工艺参数,并对沉渣镍盐进行了处理。结果表明,化学沉淀法处理化学镀镍废水的最佳工艺参数为:H2O230 mL/L,NaOH 15.67 g/L,絮凝剂聚丙烯酰胺4g/L。用硫酸处理沉淀物后镍的回收率可达97.25%。

NiO/AC非对称电容器电极材料的制备及性能研究

以硫酸镍为原料、氨水为沉淀剂,采用化学沉积法成功制备出氧化镍纳米颗粒,分别采用X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、热重分析仪(TGA)、物理吸附仪等测试手段对纳米氧化镍的物相、形貌和结构进行分析和表征。结果表明,所制得的纳米氧化镍为球形多孔颗粒,直径大约为200 nm。其中在300℃下热处理得到的氧化镍比表面积最大,为132 m2/g,平均孔径为7.3 nm。将其作为正极,活性炭作为负极,组装成非对称电容器,结果表明非对称电容器具有良好的电容性能和循环稳定性,在25 mA/g电流密度下,比电容达到1039 F/g,充放电效率高达98%以上。

镍磷化学镀镀层沉积速率影响因素研究

本文着重讨论了影响镍磷化学镀镀层沉积速率的主要因素,研究了镀液中硫酸镍浓度、次亚磷酸钠浓度、pH值、络合剂浓度及络合剂种类与化学镀镀层沉积速率的关系.实验结果表明:镍磷化学镀镀层沉积速率除随着硫酸镍浓度、次亚磷酸钠浓度、pH值、络合剂浓度的增大而加快外,还与络合剂种类有密切的关系,但当这些因素取上限值时,沉积速率不再上升,反而会出现下降的趋势.由此可得出优选的镀液配方为:硫酸镍、次亚磷酸钠浓度均为28～35 g/L,pH值5.5～6.0,并添加复合络合剂,通过溶液中镍离子的浓度确定络合剂的最佳用量.

镍覆膜碳纤维的制备与性能研究

以Ni(CO)4为前驱体,通过羰基金属化学气相沉积工艺在碳纤维表面沉积连续镍膜,从而制得镍覆膜碳纤维材料。实验给出了镍覆膜碳纤维的较佳制备工艺条件。借助SEM、EDX、XRD、冷热循环实验、断裂强度分析、差热分析等多种分析测试手段研究了镍覆膜碳纤维的性能。结果表明碳纤维表面沉积的膜层为纯镍相,连续致密,与碳纤维基底结合良好,可经受4次冷热循环而不脱落;碳纤维表面沉积连续镍膜后,其断裂强度提高了34.9%;差热分析显示沉积连续镍膜后可有效提高碳纤维的抗氧化性能。