SERS-Based Sensitive Detection of Organophosphorus Nerve Agents

Organophosphorus nerve agents, such as sarin, tabun, cyclosarin and soman, belong to the most toxic substances. So, it is very important to quickly detect it in trace-level and on-site or portable way. But, both fast and trace detections have been expected because current techniques are of low sensitivity or of poor selectivity and are time-consuming. The surface-enhanced Raman scattering (SERS)-based detection could be a suitable and effective method. However, the organophosphorus nerve agents only very weakly interact with highly SERS-activated noble metal substrates and are hardly adsorbed on them. In this case, it is difficult to detect such molecules, with reproducible or quantitative measurements and trace level, by the normal SERS technique. Recently, there have been some works on the SERS-based detection of the organophosphorus molecules. In this chapter, we introduce the main progresses in this field, including (1) the thin water film confinement and evaporation concentrating strategy and (2) the surface modification and amidation reaction. These works provide new ways for highly efficient SERS-based detection of the organophosphorus nerve agents and some other target molecules that weakly interact with the coin metal substrates

MoS 2 and WS 2 nanocone arrays: Impact of surface topography on the hydrogen evolution electrocatalytic activity and mass transport

We report the fabrication and electrochemical study of edge-abundant transition metal dichalcogenide (TMD) nanocone arrays. Time-dependent etching by sequential use of isotropic O2 and anisotropic SF6/C4F8 plasmas on nanosphere monolayer-modified TMD crystals results in very high coverage nanocone array structures with tunable aspect ratios and interspacings. Electrochemical characterization of these arrays via the hydrogen evolution reaction (HER), using a low proton concentration electrolyte (2 mM HClO4, 0.1 M NaClO4) to reveal morphology-dependent mass transport features at the proton diffusion-controlled region, show significant changes in electrocatalytic behaviour at both WS2 and MoS2: notably onset potential shifts of 100 and 200 mV, and Tafel slope decreases of 50 and 120 mV dec−1 respectively. These improvements vary according to the geometry of the arrays and the availability of catalytic edge sites, and thus the observed electrochemical behaviour can be rationalized via kinetic and mass transport effects

Atomic layer deposition functionalization and modification of three dimensional nanostructures for energy storage and conversion

In order to fulfill the increasing demands for various sustainable and renewable energy sources in future, many efforts have been paid to construct high-efficient energy storage and conversion devices for the corresponding energy sources. The boom of nanomaterials provides new opportunities for the development of high efficient energy related devices. Meanwhile, the fabrication of three-dimensional architecture nanomaterials to replace their planer counterparts for devices fabrication has been regarded as one of the promising strategy to improve the efficiency of devices. In this thesis, through effectively combining three-dimensional micro/nanoarchitecture with atomic layer deposition, we carried out a series of systematic research works on controllable fabrication, assembly and functionalization of three-dimensional micro/nanoarchitecture for high-efficient energy storage and conversion devices. The main achievements are outlined as following: 1. A low-cost and controlled assembly route was employed to construct three-dimensional aluminum doped zinc oxide transparent electrode using atomic layer deposition on varies micro/nanostructures, including three-dimensional nanopore array and three-dimensional porous nanostructure and so on. The two main properties of transparent electrode, electroconductivity and transparence of the synthesized three-dimensional aluminum doped zinc were systematically investigated by the adjusting of doping and growth conditions by atomic layer deposition. The constructed three-dimensional aluminum doped zinc oxide could serve as a good transparent electrode to be used in the new generations of photovoltaic and optoelectronic devices. 2. Core/shell nanostructures with optimal structure and composition could maximize the solar light utilization. A feasible route was performed toward scalable fabrication of well-modulated core/shell nanostructures and can be easily applied to other metal/semiconductor composites for high-performance photoelectrochemical electrodes. An aluminum nanocone array as a substrate, well-defined regular array of aluminum doped zinc oxide/titanium dioxide core/shell nanocones with uniformly dispersed gold nanoparticles was successfully realized through three sequential steps of atomic layer deposition, physical vapor deposition and annealing processes. By tuning the structural and compositional parameters, the advantages of light trapping and short carrier diffusion from the core/shell nanocone array, as well as the surface plasmon resonance and catalytic effects from the gold nanoparticles can be maximally utilized. Accordingly, a remarkable photoelectrochemical performance could be acquired. 3. A cost-effective atomic layer deposition process was introduced to realize well-defined three-dimensional platinum nanotube array based on alumina nano-porous template. Through the special introduction of a low-nitrogen-filling step and the control of atomic layer deposition conditions, continuous and smooth surface of platinum nanotube array could be obtained. And to achieve those platinum nanotube arrays, half numbers of the atomic layer deposition cycles and 10% platinum precursor pulsing time are only needed, compared to conventional atomic layer deposition process. The achieved platinum nanotube array was explored as a current collector to construct three-dimensional core/shell platinum/manganese dioxide nanotube array for supercapacitors. The constructed three-dimensional core/shell nanostructure electrode exhibited a high specific capacitance, an excellent rate capability and a negligible capacitance loss after long-term charging-discharging cycling. 4. An ultra-low loading amount of ultrasmall platinum nanoparticles on three-dimensional bacterial cellulose derived carbon nanofiber was achieved by using a convenient modified atomic layer deposition process. The ultrasmall platinum nanoparticles surface-modified three-dimensional carbon nanofiber exhibited good electrocatalytic activity and stability towards hydrogen evolution reaction. The synthesis process provides a general strategy for minimizing the demand of precious metal catalysts while maintaining their high catalytic efficiency. The achieved results within this dissertation on three-dimensional nanostructures fabrication and functionalization, and the integration in energy storage and conversion device should provide a strong insight and guidance on the design and structure of the high efficient energy storage and conversion devices.Um der steigende Nachfrage nach nachhaltigen und erneuerbaren Energiequellen in der Zukunft gerecht zu werden, wurden viele Anstrengen unternommen um hoch effiziente Energiespeicher und Bauelemente zur Energieumwandlung zu entwickeln. Insbesondere bieten Nanomaterialien neue Möglichkeiten um energiebezogene Bauelemente noch effizienter zu machen. Hier verspricht man sich von der Herstellung von dreidimensionalen Nanostrukturen weitere Effizienzsteigerungen im Vergleich zu planaren Strukturen. In dieser Arbeit werden hocheffiziente Energiespeicher und -umwandler durch die effektive Kombination von dreidimensionaler Mikro- und Nanotechnologie mit Atomlagenabscheidung hergestellt und systematisch charakterisiert. Im Folgenden die wichtigsten Ergebnisse: 1. Dreidimensionale nanoporöse Aluminiumdotierte Zinkoxid Elektroden wurden kostengünstig und kontrolliert mit Hilfe von Atomlagenabscheidung hergestellt. Die wichtigsten Parameter, Transparenz und elektrische Leitfähigkeit der Elektrode, wurde systematisch charakterisiert und der Einfluss der Dopingkonzentration und der Wachstumsbedingungen wurde analysiert. Es hat sich herausgestellt, dass die dreidimensionalen nanoporöse Aluminiumdotierte Zinkoxid Elektroden sich insbesondere als gute transparente Elektroden in der Photovoltaik und in optoelektronischen Bauelementen eignen. 2. Kern/Mantelnanostrukturen mit optimierter Struktur und Zusammensetzung können die ausbaute von Sonnenlicht deutlich erhöhen. Eine vielversprechende Route mit starkem Fokus auf die skalierbare Herstellung von gut modulierten Kern/Mantel-Nanostrukturen wurde entwickelt, welche leicht an andere Metall und Halbleiter für photoelektrochemische Elektroden angepasst werden kann. Als Substrat dient ein regelmäßig angeordnetes Aluminium nano-Kegel-Array, welches mit einer Aluminium-dotiertem Zinkoxid / Titandioxid Kern/Mantel Struktur und regelmäßig verteilten Goldnanopartikeln überzogen ist. Die Herstellung wurde Hilfe von Atomlagenabscheidung, physikalischer Dampfabscheidung und einem Glühprozess realisiert. Durch gezielte Abstimmung der Struktur und Zusammensetzung konnte der Lichteinfang verbessert und die Ladungsträgerdiffusion optimiert werden. Plasmonenresonanz und katalytische Effekte konnten durch Goldnanopartikel kontrolliert werden. Dementsprechend konnte eine bemerkenswerte photoelektrochemische Leistungsfähigkeit erzielt werden. 3. Ein kostengünstiger Prozess für die Synthese von dreidimensionalen Platin Nanoröhren-Arrays, basierend auf der Atomlagenabscheidung und nanoporösen Templaten, wurde entwickelt. Dies gelang durch die Einführung eines low-nitrogen-filling Schritts. Kontinuierliche Platin Nanoröhren mit glatter Oberfläche wurden erzielt. Dabei wurde die Anzahl der Zyklen halbiert und die Pulszeit des Platinprecursors um 10 % reduziert im Vergleich zu herkömmlichen Verfahren. Die hergestellten Platinnanoröhren-Arrays wurden als Stromkollektoren für dreidimensionale Pt/MnO2 Kern/Mantel Strukturen in Superkondensatoren eingesetzt. Die synthetisierte Struktur zeigte eine hohe spezifische Kapazität, gute Performance unter schneller Entladung und eine gute Zyklenbeständigkeit. 4. Eine ultra-niedrige Lademenge von sehr kleinen Platin Nanopartikeln auf Kohlenstoffnanofasern, welche mittels bakterieller Zellulose hergestellt wurde, wurde mit Hilfe der Atomlagenabscheidung erzielt. Die mit Platinpartikeln oberflächenmodifizierte Kohlenstoffnanofasern zeigten gute elektrokatalytische Aktivität und Stabilität gegenüber der Wasserstoffentwicklungsreaktion. Das Syntheseverfahren stellt eine allgemeine Strategie dar, um den Einsatz von Edelmetallkatalysatoren unter Beibehaltung ihrer hohen katalytischen Effizienz zu minimieren. Die im Rahmen dieser Arbeit erzielten Ergebnisse in Bezug auf die Herstellung von dreidimensionalen Nanostrukturen, ihre Funktionalisierung und die Implementierung in Bauelemente zur Energiespeicherung und -umwandlung, sollte eine starke Basis für zukünftige Bauelemente mit verbesserter Leistung liefern

Catalyst Engineering for Growth of One-Dimensional Nanostructures

Ph.DDOCTOR OF PHILOSOPH

Towards High Solar to Fuel Efficiency: From Photonic Design, Interface Study, to Device Integration

Efficient unassisted solar fuel generation, a pathway to storable renewable energy in the form of chemical bonds, requires optimization of a photoelectrochemical device based on photonic design and interface study. We first focused on enhancing absorption via nanophotonic design of light absorbers. Near-unity, broadband absorption in sparse InP nanowire arrays with multi-radii and tapered nanowire array designs are simulated and experimentally demonstrated. Later, a few strategies are introduced to achieved high solar-to-fuel efficiency. Optically, photoelectrochemical device would require the catalyst ensembles to be highly transparent. We report a record solar-to-hydrogen efficiency by integrating Rh nanoparticle catalysts onto photocathodes with minimal parasitic absorption and reflection losses in the visible range. The other two light management strategies have been developed and experimentally verified to create highly active and effectively transparent catalyst structures: i) arrays of mesophotonic dielectric cone structures that serve as tapered waveguide light couplers to efficiently guide incident light through apertures in an opaque catalyst into the light absorber, and ii) an effectively transparent catalyst consisting of arrays of micron-scale triangular cross-sectional metal grid fingers, which are capable of redirecting the incoming light to the open areas of the PEC cell without shadow loss. The electronic properties of the surface films exposed to the electrolyte are also critical. The anatase TiO₂ protection layer on the photocathode creates a favorable internal band alignment for hydrogen evolution, promoting the transport of the excess electrons and inhibiting voltage drops. The interfacial conduction mechanism between the defected TiO₂ and metal catalysts is investigated. A combinatorial approach of electrochemistry, X-ray photoelectron spectroscopy, and resonant X-ray spectroscopy reveals the correlation between the interfacial quasi-metal phase with TiO₂ properties. By careful control of gas diffusion electrode assembling to maintain appropriate wetted catalyst interface, another record solar-to-CO efficiency with extended stability can be realized.</p

From 2D CoCrPt:SiO2 films with perpendicular magnetic anisotropy to 3D nanocones — A step towards bit patterned media —

Due to the ever-increasing worldwide consumption of memory for digital information, new technologies for higher capacity and faster data storage systems have been the focus of research and development. A step towards achieving higher data storage densities or magnetic recording media is the concept of bit patterned media, where the magnetic recording layer is divided up into magnetically isolated bit units. This approach is one of the most promising technologies for increasing data storage densities and could be implemented by nanostructuring the wafer. Therefore, the fabrication of the appropriate nanostructures on a small scale and then be able to manufacture these structures on an industrial scale is one of the problems where science and industry are working on a solution. In addition, the answer to the open question about the influence that patterning on the nano length scale has on the magnetic properties is of great interest. The main goal of this thesis is to answer the open question, which magnetic properties can be tailored by a modification of the surface texture on the nanometre length scale. For this purpose the following properties: anisotropy, remanence, coercivity, switching field distribution, saturation magnetisation, Gilbert damping, and inhomogeneous linebroadening were compared between planar two dimensional thin ferromagnetic films and three dimensional magnetic structures. In addition, the influences of the tailored morphology on the intergranular or the exchange coupling between the structures, which is called interdot exchange coupling, was investigated. For the ferromagnetic thin films, the focus of the investigations was on the granular CoCrPt:SiO2 and [Co/Pd] layer, which currently are the state-of-the-art material for magnetic data storage media. These materials are characterised by their high coercivity and high perpendicular anisotropy, which has a low spatial distribution in the preferred direction of magnetisation. In this work the pre-structured GaSb(001) substrate with self-assembled periodic nanocone structures at the surface are used. The preparation by ion beam erosion of these structures is simple, fast, and highly reproducible and therefore this method is particularly beneficial for fundamental research. To compare the 2D thin films with the 3D magnetic structures, besides the pre-structured specimen, planar samples were also fabricated. The first sample series prepared was coated by Py. Due to the fact that the magnetic properties of this material are well-known, it was also possible to do some OOMMF simulations in addition to the VNA-FMR and MOKE measurements. Afterwards two planar samples with CoCrPt and CoCrPt:SiO2 were prepared. The planar CoCrPt:SiO2 samples were Co+ ion implanted to study the influence of such irradiation on the intergranular and interdot exchange coupling, switching field distribution, and in particular on the spin dynamics. Moreover, both samples were measured by TRMOKE in order to obtain information about the spin dynamics. Subsequently, the perpendicular storage media materials CoCrPt:SiO2 and [Co/Pd] were deposited on a prestructured GaSb(001) nanocone substrate surface. These sample series were measured by MOKE, SQUID, and vector-VSM. The measurements demonstrate the influence of the periodicity and height of the nanocones on the intergranular and interdot exchange coupling. They also show the reorientation of the magnetisation with respect to the curvature of the substrate template and furthermore, the morphology-induced influences on the magnetic domains. From the comparison between the results for the planar and the pre-structured samples, a decrease of the interdot exchange coupling was observed, which scales together with the periodicity of the nanocone pattern. In addition, it was shown that for all samples with thin magnetic films on nanocones,the magnetisation aligns along the curvature of the underlying nanocone structure. For Py on nanocones, planar granular CoCrPt:SiO2, and planar granular CoCrPt, measurements by VNA-FMR and TRMOKE could be carried out, which yielded information about the spin dynamics. The results obtained for both of the planar sample are comparable to values from the literature for the Gilbert damping. The results for the Py samples showed that the commonly used 2D model resonance condition is, in case of a 3D magnetic structure, no longer valid due to the alignment of the magnetisation along the underlying substrate structure and therefore an new model has to be derived.Aufgrund des weltweiten, immer weiter steigenden Bedarfs an Speicherplatz von digitalen Information, sind neue Technologien für größere und schnellere Speichermedien im Fokus von Forschung und Entwicklung. Ein Schritt hin zu einer höheren Speicherdichte in der magnetischen Datenspeicherung ist dabei das sogenannte Konzept der ”Bit patterned media”, das definierte Informationseinheiten auf regelmäßig angeordneten Nanostrukturen beschreibt. Dieser Ansatz ist einer der derzeit vielversprechendsten Optionen die Speicherdichte zu erhöhen. Dabei ist die Herstellung der benötigten Nanostrukturen und deren Skalierung hin zu makroskopischen Dimensionen eines der Probleme an deren Lösung die Wissenschaft und Industrie derzeit arbeitet. Desweiteren ist die Antwort auf die noch offene Frage nach der Beeinflussung der nanoskaligen Strukturen auf die magnetischen Eigenschaften von großem Interesse. Das Hauptziel in dieser Arbeit ist es, einen Beitrag zur Beantwortung der Frage, welche magnetischen Eigenschaften sich durch eine Veränderung der Oberflächenstruktur im Nanometerbereich beeinflussen lassen, zu leisten. Hierzu wurden die folgenden Eigenschaften, wie zum Beispiel die Anisotropie, Remanenz,Koerzitivität, Schaltfeldverteilung, Sättigungsmagnetisierung, Gilbertdämpfung und inhomogene Linienverbreiterung von planaren zweidimensionalen dünnen ferromagnetische Schichten mit denen von dreidimensionalen magnetischen Strukturen verglichen. Zusätzlich wurde der Einfluss der angegpassten Morphologie auf die intergranularen- beziehungsweise auf die zwischen den Strukturen wirkende (interdot) Austauschkopplung untersucht. Der Hauptaugenmerk bei den ferromagnetisch dünnen Schichten lag dabei auf den granularen CoCrPt:SiO2 und [Co/Pd] Filmen, die heutzutage ein Standardmaterial für die magnetischen Speichermedien darstellen. Diese Materialien zeichnen sich durch eine hohe Koerzivität und senkrechte Anisotropie, mit geringer räumlicher Verteilung der Vorzugsrichtung der Magnetisierung, aus. Die hier vorgestellten vorstrukturierten GaSb(001) Substrate mit selbstordnenden periodischen Nanokegeln auf der Oberfläche, sind mittels Ionenstrahlerosion einfach, schnell und sehr gut reproduzierbar herzustellen. Deshalb ist diese Methode besonders für die Grundlagenforschung von Vorteil. Um einen Vergleich zwischen 2D Filmen und 3D Strukturen ziehen zu können, wurden neben den vorstrukturierten Substraten auch planare Proben beschichtet. Eine erste Versuchsreihe wurde mit einem dünnen Py Film präpariert. Da dessen magnetische Eigenschaften wohlbekannt sind, konnten neben den Untersuchungen mit VNA-FMR und MOKE auch einige OOMF Simulationen erstellt werden. Danach wurden zwei Proben mit planarem CoCrPt beziehungsweise CoCrPt:SiO2 untersucht. Bei den planaren CoCrPt:SiO2 Proben wurden außerdem noch Co+ Ionen implantiert, um deren Auswirkungen auf die intergranulare Austauschkopplung, Schaltfeldverteilung und besonders auf die Spindynamik zu bestimmen. Bei beiden Probensystemen konnte zusätzlich die Spindynamik mittels zeitaufgelöstem MOKE gemessen werden. Im Anschluss wurden die beiden senkrechten Speichermedien CoCrPt:SiO2 and [Co/Pd] auf Substraten mit Nanokegeln vorstrukturierten GaSb(001) Oberflächen abgeschieden. Diese Proben wurden mit MFM, MOKE, SQUID und Vektor-VSM vermessen. Aus den Messungen konnnten dann die Einflüsse auf die intergranulare- beziehungsweise interdot Austauschkopplung in Abhängigkeit von der Periodizität und Höhe der Nanokegel bestimmt werden, sowie die Umorientierung der Magnetisierung bezüglich der Substratkrümmung und den Morphologie induzierten Einfluss auf die magnetischen Domänen. Anhand der Vergleiche zwischen den Messungen der planaren und den vorstrukturierten Proben konnte eine Verringerung der Austauschkopplung zwischen den Strukturen gezeigt werden, die mit der Nanokegelstrukturperiodizität skaliert. Außerdem wurde in allen dünnen magnetischen Filmen auf Nanokegeln gezeigt, dass die Magnetisierung sich in Abhängigkeit der darunterliegenden Struktur ausrichtet. Bei den Py auf Nanokegeln, den planaren CoCrPt und dem planaren CoCrPt:SiO2 Proben konnten außerdem mit VNA-FMR und TRMOKE Informationen bezüglich der Spindynamik gemessen werden. Die erzielten Ergebnisse, der beiden planaren Proben, sind vergleichbar mit denen, aus der Literatur bekannten Werten, für die Gilbertdämpfung. Darüber hinaus wurde durch die Messungen an den Py Proben gezeigt, dass die Theorie, des bisher genutzten 2D Modells, nicht mehr gültig ist, da sich die Magnetisierung entlang der Substratstruktur ausrichtet, und deshalb ein neues Model aufgestellt werden muss

Boosting solar energy harvesting with ordered nanostructures fabricated by anodic aluminum oxide templates

To date, technical development has boosted the efficiencies of solar energy conversion devices with conventional planar architectures to be close to the respective theoretical values, which are hard to be further improved without reforming the device structures. Alternatively, ordered nanostructure arrays have recently emerged as efficacious scaffolds to construct devices for converting energy more efficiently due to their advantageous optical effects. To meet the global energy requirements for producing renewable energy efficiently, a general approach is needed to fabricate diverse ordered nanostructure arrays. In the meantime, the approach should allow for fine tuning in every set of nanounits towards obtaining desired properties. Herein, we utilized anodic aluminum oxide (AAO) templates to provide a versatile method for constructing ordered nanostructure arrays from one to two dimensions. Firstly, arrays of one-dimensional Au nanowires comprising two components of pillar and truncated pyramid were fabricated. Then, periodic one-dimensional Janus hetero-nanostructures with programmable morphologies, compositions, dimensions, and interfacial junctions were realized. Finally, two-dimensional superlattice photonic crystals with two sets of nanopores were constructed via a combination of the AAO template and the structural replication technique. Subsequently, these as-obtained nanostructures were integrated into photoelectrochemical water-splitting cells and solar-to-thermal conversion systems, which significantly boosted solar energy harvesting performance. In conjunction with theoretical simulations, we further elucidated that the enhanced light harvesting ability can be ascribed to twofold facts: photonic effects and surface plasmon resonance which thus provide a route to manipulate light at the nanoscale.In dieser Dissertation habe ich drei Arten von hochgeordneten Nanostrukturen realisiert, einschließlich 1D-PTP-Au-Core / CdS-Shell-Array, Au-NW / TiO2-NT-Janus-Hetero-Nanostruktur-Array und 2D-Metall-SPhCs. Diese fortschrittlichen Architekturen könnten als vielseitige Gerüste zum Aufbau energiebezogener Geräte eingesetzt werden und haben ein großes Potenzial, die Gesamtleistung drastisch zu verbessern und die durch die planare Konfiguration auferlegten Grenzen zu durchbrechen. Insbesondere die geordneten Nanostruktur-Arrays mit mehreren Komponenten sind von großer Bedeutung, und die entsprechenden Geräte können die Vorteile dieser nanostrukturierten Komponenten kombinieren, wodurch die relevante Leistung systematisch verbessert wird. Darüber hinaus ermöglichen die hohe Regelmäßigkeit der Nanostrukturverteilung, die Gleichmäßigkeit der Nanounits sowie die steuerbaren Größen und Profile der Nanostruktur die resultierenden Architekturen als leistungsfähige Plattform, um die spezifischen Energieumwandlungsreaktionen mikroskopisch zu untersuchen. Diese Ergebnisse könnten wiederum die weitere Entwicklung der relevanten Geräte leiten

알칼리 수전해를 위한 Fe가 함유된 Ni-Mo-P 나노 어레이 촉매의 제조

학위논문(석사)--서울대학교 대학원 :융합과학기술대학원 나노융합학과,2019. 8. 박원철.수전해를 통한 수소 및 산소발생 기술은 화석연료의 고갈 및 화석연료 사용에 따른 환경오염문제를 해결 할 수 있는 기술 중 하나로 각광받고 있다. 열역학적으로 수전해에 필요한 에너지는 1.23 V이다. 하지만 산소 및 수소발생 반응의 복잡한 반응경로 및 반응생성물로 인해 실제로 1.23 V이상의 전압이 필요하고, 이를 과전압이라 한다. 현재 반응에 필요한 과전압을 낮추기 위해 산업적으로 사용되는 촉매는 Pt 및 RuO2, IrO2 과 같은 귀금속 기반의 촉매물질이다. 하지만 이들은 매장량이 적어 가격 경쟁력이 떨어지고, 낮은 내구성 문제로 대량화에 어려움이 있다. 따라서 귀금속 촉매를 대체할 수 있는 새로운 물질을 개발하는 것이 필요하다. 본 연구는 Fe가 포함된 Ni-Mo-P 어레이를 니켈 폼위에 성장 (NMFP) 시키는 방법을 제시하고, 이 물질이 효율적인 수전해 촉매로 사용될 수 있음을 증명하였다. NMFP는 수열합성법을 통해 NiMoO4·xH2O를 니켈 폼위에 성장시킨 후 (NMO), 표면에 니켈-철 프루시안 블루 아날로그 (Ni-Fe PBA)를 합성한 뒤, 인 도핑을 통해 합성 할 수 있다. 합성 과정에서 NMO는 PBA가 잘 분리되어 성장 할 수 있도록 돕는 템플릿 및 Ni 이온 제공원으로서 작용하고, K3[Fe(CN)6 는 Ni-Fe PBA의 Fe 이온 및 유기 링커로 작용한다. 합성된 NMFP는 Fe 첨가 효과 및 많은 활성점이 노출 되어 있는 정렬된 나노로드 구조로 인해 알칼라인 전해질 (1.0 M KOH)에서 우수한 HER, OER 성능을 나타냈으며, 40시간 반응 후에도 성능 저하를 거의 보이지 않았다. NMFP를 양극, 음극으로 사용한 셀은 100 mA·cm-2 가 회로에 흐르기 위해 1.63 V (과전압 400 mV)의 전압이 필요하고, 3000 사이클 사용 후에도 우수한 성능을 나타냈다.The production of hydrogen and oxygen via electrolysis is being recognized as a rising technology to handle the future energy crisis. Thus, fabricating highly active and cost-effective electrocatalysts toward HER and OER is essential to improve the water splitting efficiency. Herein, the Fe-incorporated Ni-Mo-P array on nickel foam (denoted NMFP) was synthesized and used as electrocatalyst for overall water splitting in alkaline media. The preparation of NMFP begins with a hydrothermal treatment of NiMoO4·xH2O nanoarray on nickel foam (denoted as NMO), followed by the modification of Prussian blue analogue (PBA). After the subsequent phosphorization process, the NMFP is successfully synthesized. In the synthesis procedure, NiMoO4∙xH2O serves as a sacrificial template and K3[Fe(CN)6] acts as Fe sources as well as an organic linker for growth of Ni-Fe PBA on it. As a result, NMFP exhibits remarkable catalytic activity and long term performance in both HER and OER in 1.0 M KOH. In addition, overall water splitting cell with using NMFP as both the cathode and anode has small operating voltage and long-term operation with little loss of activity in 1.0 M KOH. This research can broaden an insight into the fabrication of polymetallic compounds with well-organized to further improve water electrolysis. Furthermore, the proposed synthesis method can be extended to a variety of energy storage and conversion applications.1. Introduction 13 1.1. Electrochemical water splitting in alkaline media 13 1.2. TMPC for overall water splitting 14 1.3. Fabrication strategies for efficient electrocatalysts 15 1.4. The purpose of our research 16 2. Experimental 17 2.1. Reagents 17 2.2. Preparation of NMO 17 2.3. Preparation of NMF 18 2.4. Preparation of NMFP and NMOP 18 2.5. Material characterizations 19 2.6. Electrochemical measurements 20 3. Result and Discussion 21 3.1. Material analysis 21 3.2. Electrochemical analysis 38 4. Conclusion 59 References 60 국문 초록 (Abstract in Korean) 75Maste