2,182 research outputs found

    Optimization of photoelectrochemical water splitting performance in the presence of ascorbic acid

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    Cilj ovog rada bio je ispitati fotoelektrokemijski proces dobivanja vodika upotrebom TiO2 i SnS2 elektroda uz askorbinsku kiselinu kao žrtvujuće sredstvo. Sva mjerenja provedena su u otopini 0,1 M NaCl sa i bez askorbinske kiseline. Ispitivanje elektroda provodilo se metodom linearne promjene potencijala (LSV), elektrokemijskom impedancijskom spektroskopijom (EIS), kronoamperometrijom (CA) i mjerenjem potencijala otvorenog kruga (OCP). Adsorpcija askorbinske kiseline na fotokatalitički materijal praćena je metodom UV/VIS spektrofotometrije dok je plinskom kromatografijom određena količina vodika koja se razvija u procesu. Dobivanje vodika se provodilo metodom kronoamperometrije u trajanju od dva sata u atmosferi argona. Vodik je uspješno dobiven, a veće količine dobivene su na SnS2 elektrodi nego na TiO2 elektrodi. Uspoređujući odzive linearne polarizacije osvijetljene i neosvijetljene elektrode, uočava se kako pod djelovanjem svjetla struja raste što znači da su obje elektrode fotoaktivne. Upotrebom askorbinske kiseline dolazi do povećanja fotostruja što je dokaz da askorbinska kiselina djeluje kao žrtvujuće sredstvo. Osim fotostruja, pri potencijalima većim od 0,5 V uočavaju se značajan porast struje koji je posljedica elektrokemijske oksidacije askorbinske kiseline.The aim of this work was to study the photoelectrochemical process of hydrogen production using TiO2 and SnS2 electrodes with ascorbic acid as a sacrificial agent. All measurments were performed in 0.1 M NaCl solution with and without ascorbic acid. The electrodes were tested using linear sweep voltametry (LSV), electrochemical impedance spectroscopy (EIS), chronoamperometry (CA) and open circuit potential (OCP) monitoring. The adsorption of ascorbic acid on the photocatalytic material was monitored by using UV/VIS spectrophotometry, while the amount of hydrogen generated in the process was determined by gas chromatograpy. Hydrogen was produced using the chronoamperometry method during two hours in an argon atmosphere. Hydrogen was successfully obtained, and larger amounts were produced in the process involving SnS2 photoelectrode than in the process involving TiO2 photoelectrode. The linear voltammetry responses of illuminated and non-illuminated electrodes indicate that illumination results in a current increase which is the evidence that both electrodes are photoactive. The ascorbic acid addition increases the photocurrent value. The significant current increase in ascorbic acid solution, observed at potentials more positive than 0.5 V, is the result of electrochemical reaction

    Development and characterisation of Zn-ion battery based on V2O5

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    U ovom radu provedena je karakterizacija reduciranog grafenova oksida (rGO) u troelektrodnom sustavu. Također, provedena je sinteza i karakterizacija rGO papira. Cilj rada bio je dobiti fleksibilan samostojeći materijal pogodan za depoziciju cinka. U tu svrhu priređen je rGO papir s ugrađenim ugljikovim nanocjevčicama (CNT) postupkom elektrokemijske redukcije pri -1,4 V. rGO/CNT papir upotrijebljen je kao anoda u cink-ionskoj bateriji uz rGO/V2O5 papir kao katodu. Karakterizacija baterije provedena je metodama kronoamperometrije (CA), cikličke voltametrije (CV) i elektrokemijske impedancijske spektroskopije (EIS). Na dobivenim cikličkim voltamogramima zabilježeni su strujni vrhovi koji odgovaraju taloženju/otapanju cinka te strujni vrhovi koji odgovaraju redoks reakciji V2O5. Vrijednosti specifičnog kapaciteta, Cs, rGO-CNT-Zn/rGO-V2O5 baterije dobivene metodom CV kreću se od 30,16 mAh g^-1 do 172,53 mAh g^-1 . Također, proveden je galvanostatski proces punjenja i pražnjenja baterije. Tom metodom dobiveni su specifični kapaciteti u rasponu od 1,83 mAh g^−1 pri najvećoj jakosti struje do 170,13 mAh g^−1 pri najmanjoj vrijednosti struje. Prije nego što je ispitana baterija, provedena je i karakterizacija elektroda (rGO, rGO/CNT, rGO/MXene i rGO/V2O5) u troelektrodnom sustavu koristeći pri tome kronoamperometriju za redukciju GO i cikličku voltametriju kako bi se deponirao cink na rGO i rGO modificiranim slojevima nanesenima na elektrodu staklastog ugljika (GC).In this work, reduced graphene oxide (rGO) was charachterised in three-electrode system. Synthesis and characterization of rGO paper was also carried out. The aim of the work was to obtain a flexible free-standing material suitable for zinc deposition. For this purpose, rGO paper containing carbon nanotubes (CNT) was prepared by electrochemical reduction at -1.4 V. rGO/CNT paper was used as the anode in a zinc-ion battery while rGO/V2O5 paper was used as the cathode. Characterization of the battery was carried out using chronoamperometry (CA), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods. In the resulting cyclic voltammograms, current peaks corresponding to the deposition/dissolution of zinc and current peaks corresponding to the redox reaction of V2O5 were recorded. The values of the specific capacity, Cs, of rGO-CNT-Zn/rGO-V2O5 batteries obtained by the CV method range from 30.16 mAh g^-1 to 172.53 mAh g^-1. Also, a galvanostatic process of charging and discharging the battery was carried out. Using this method, specific capacities ranging from 1.83 mAh g^−1 to 170.13 mAh g^−1 were recorded. Before the battery was tested, the rGO electrodes containing CNT, MXene or V2O5 (rGO, rGO/CNT, rGO/MXene and rGO/V2O5) were characterized in a three-electrode system. Reduction of GO was carried out by chronoamperomertry and Zn deposition at rGO, rGO/CNT and rGO/MXene electrodes was carried out by cyclic voltametry

    Development and characterisation of Zn-ion battery based on V2O5

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    U ovom radu provedena je karakterizacija reduciranog grafenova oksida (rGO) u troelektrodnom sustavu. Također, provedena je sinteza i karakterizacija rGO papira. Cilj rada bio je dobiti fleksibilan samostojeći materijal pogodan za depoziciju cinka. U tu svrhu priređen je rGO papir s ugrađenim ugljikovim nanocjevčicama (CNT) postupkom elektrokemijske redukcije pri -1,4 V. rGO/CNT papir upotrijebljen je kao anoda u cink-ionskoj bateriji uz rGO/V2O5 papir kao katodu. Karakterizacija baterije provedena je metodama kronoamperometrije (CA), cikličke voltametrije (CV) i elektrokemijske impedancijske spektroskopije (EIS). Na dobivenim cikličkim voltamogramima zabilježeni su strujni vrhovi koji odgovaraju taloženju/otapanju cinka te strujni vrhovi koji odgovaraju redoks reakciji V2O5. Vrijednosti specifičnog kapaciteta, Cs, rGO-CNT-Zn/rGO-V2O5 baterije dobivene metodom CV kreću se od 30,16 mAh g^-1 do 172,53 mAh g^-1 . Također, proveden je galvanostatski proces punjenja i pražnjenja baterije. Tom metodom dobiveni su specifični kapaciteti u rasponu od 1,83 mAh g^−1 pri najvećoj jakosti struje do 170,13 mAh g^−1 pri najmanjoj vrijednosti struje. Prije nego što je ispitana baterija, provedena je i karakterizacija elektroda (rGO, rGO/CNT, rGO/MXene i rGO/V2O5) u troelektrodnom sustavu koristeći pri tome kronoamperometriju za redukciju GO i cikličku voltametriju kako bi se deponirao cink na rGO i rGO modificiranim slojevima nanesenima na elektrodu staklastog ugljika (GC).In this work, reduced graphene oxide (rGO) was charachterised in three-electrode system. Synthesis and characterization of rGO paper was also carried out. The aim of the work was to obtain a flexible free-standing material suitable for zinc deposition. For this purpose, rGO paper containing carbon nanotubes (CNT) was prepared by electrochemical reduction at -1.4 V. rGO/CNT paper was used as the anode in a zinc-ion battery while rGO/V2O5 paper was used as the cathode. Characterization of the battery was carried out using chronoamperometry (CA), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods. In the resulting cyclic voltammograms, current peaks corresponding to the deposition/dissolution of zinc and current peaks corresponding to the redox reaction of V2O5 were recorded. The values of the specific capacity, Cs, of rGO-CNT-Zn/rGO-V2O5 batteries obtained by the CV method range from 30.16 mAh g^-1 to 172.53 mAh g^-1. Also, a galvanostatic process of charging and discharging the battery was carried out. Using this method, specific capacities ranging from 1.83 mAh g^−1 to 170.13 mAh g^−1 were recorded. Before the battery was tested, the rGO electrodes containing CNT, MXene or V2O5 (rGO, rGO/CNT, rGO/MXene and rGO/V2O5) were characterized in a three-electrode system. Reduction of GO was carried out by chronoamperomertry and Zn deposition at rGO, rGO/CNT and rGO/MXene electrodes was carried out by cyclic voltametry

    ANALISIS KELAYAKAN BISNIS PEMANFAATAN BIOMASSA DAUN DAN MAHKOTA NANAS SEBAGAI BAHAN DASAR UTAMA SUPERKAPASITOR

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    Kebutuhan akan energi terus meningkat setiap tahunnya dan sebagian besar energi berasal bergantung dari energi fosil. Laju pertumbuhan penduduk ditambah dengan laju pertumbuhan ekonomi sangat meningkatkan kebutuhan negara terhadap energi. Dengan masalah tersebut Pemerintah Indonesia mendorong kebijakan dalam pemanfaatan EBT untuk mengurangi ketergantungan pada energi fosil. Kebijakannya berupa meningkatkan pemanfaatan biomassa sebagai energi baru terbarukan. Salah satu pemanfaatan biomassa berupa penggunaan limbah mahkota nanas dan daun nanas sebagai bahan dasar pembuatan superkapasitor.Penelitian ini bertujuan untuk menganalisa kelayakan industri dari superkapasitor dengan bahan dasar mahkota dan daun nanas sebagai alat penyimpan energi terbarukan. Studi kelayakan dilakukan dengan menghitung aspek ekonomi pada penjualan superkapasitor. Setelah melakukan perhitungan aspek ekonomi menggunakan metode BEP, PP, NPV, PI, dan IRR ditentukan bahwa usaha superkapasitor berbahan dasar biomassa mahkota dan daun nanas layak diindustrikan. Kata Kunci : Biomassa, Kelayakan Bisnis, BEP, PP, NPV, PI, IRR

    The Use of Silver Rotating Disk Electrode to Suppress Passivation During Voltammetric Determination of 4-Nitrophenol

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    In this bachelor's thesis results of the optimization of the measurement of 4-nitrophenol (1·10-4 mol·l-1 ) in the Britton-Robinson (BR) buffer medium on the silver rotating disk electrode are presented with the aim of suppressing the passivation of the electrode surface. The parameters of the differential pulse voltammetry (DPV) technique were optimized for the analytical use of the rotating disk electrode. In BR buffer pH 4,0 and at the electrode rotation speed of 250 rpm calibration dependences of 4-nitrophenol was obtained in the range of (1-10) ·10-5 mol·l-1 under selected optimal conditions and different methods of electrode surface pretreatment. The limit of quantification (LOQ) achieved with polishing before each measurement was 1,7·10-6 mol·l-1 and with polishing only before the concentration change was 8,8·10-6 mol·l-1 .V této bakalářské práci jsou předloženy výsledky optimalizace měření 4-nitrofenolu (1·10-4 mol·l-1 ) v prostředí Brittonova-Robinsonova (BR) pufru na stříbrné rotující diskové elektrodě s cílem potlačit pasivaci povrchu elektrody. Pro analytické využití rotující diskové eleketrody byly optimalizovány parametry techniky diferenční pulzní voltametrie (DPV). V prostředí BR pufru pH 4,0 a při rychlosti rotace elektrody 250 rpm byly získány kalibrační závislosti 4-nitrofenolu v rozmezí (1-10) ·10-5 mol·l-1 . Dosažená mez stanovitelnosti (LOQ) s leštěním před každým měřením byla 1,7·10-6 mol·l-1 a s leštěním pouze před změnou koncentrace byla 8,8·10-6 mol·l-1 .Katedra analytické chemieDepartment of Analytical ChemistryFaculty of SciencePřírodovědecká fakult

    Development of 3D printed enzymatic biofuel cells for powering implantable biomedical devices

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    The drive toward device miniaturisation in the field of enzyme-based bioelectronics established a need for multi-dimensional geometrically structured and highly effective microelectrodes, which are difficult to implement and manufacture in devices such as biofuel cells and sensors. Additive manufacturing coupled with electroless metal plating enables the production of three-dimensional (3D) conductive microarchitectures with high surface area for potential applications in such devices. However, interfacial delamination between the metal layer and the polymer structure is a major reliability concern, which results in device performance degradation and eventually device failure. This thesis demonstrates a method to produce a highly conductive and robust metal layer on a 3D printed polymer microstructure with strong adhesion by introducing an interfacial adhesion layer. Prior to 3D printing, multifunctional acrylate monomers with alkoxysilane (-Si-(OCH3)3) were synthesised via the Thiol-Michael addition reaction between pentaerythritol tetraacrylate (PETA) and 3-mercaptopropyltrimethoxysilane (MPTMS) with a 1:1 stoichiometric ratio. Alkoxysilane functionality remains intact during photopolymerisation in a projection micro-stereolithography (PµSLA) system and is utilised for the sol-gel reaction with MPTMS post-functionalisation of the 3D printed microstructure to build an interfacial adhesion layer. This functionalisation leads to the implementation of abundant thiol functional groups on the surface of the 3D printed microstructure, which can act as a strong binding site for gold during electroless plating to improve interfacial adhesion. The 3D conductive microelectrode prepared by this technique exhibited excellent conductivity of 2.2×107 S/m (53% of bulk gold) with strong adhesion between a gold layer and a polymer structure even after harsh sonication and adhesion tape test, which offers potential to build a robust 3D conductive microarchitecture for applications such as biosensors and biofuel cells. As a proof-of-concept, the microelectrode with gold-coated complex lattice geometry was employed as an enzymatic glucose anode, which showed a significant increase in the current output compared to the one in the simple cube form. As the first approach, glucose oxidase was used as an enzyme. To find the optimal protocol for the enzyme immobilisation, the enzyme was first immobilised on agarose to achieve the enzyme’s highest activity and stability. Then, this immobilisation protocol was applied to immobilise the enzyme on the gold electrode surface. Preliminary studies on the preparation of 3D gold diamond lattice microelectrode modified with cysteamine and glucose oxidase as a bioanode for single cell enzymatic biofuel cell (EFC) application were performed, which demonstrated high current density of 0.38 μA cm–2 at 0.35 V in glucose solutions. This method for fabrication of 3D conductive microelectrodes offers potential for several biological applications. Instead of using a thiol, the surface of the 3D-printed part can be functionalised with different other functional groups to create an appropriate surface for biomolecules and cell adhesion. Furthermore, the surface of thiol functionalised printed parts can be perfect for additional metal coatings, opening the door to the creation of highly efficient and customised implantable energy harvesters and biosensors

    Analisis Pengaruh Kadar Aluminium Pada Katoda Litium Nikel Mangan Aluminium (LiNi0,9MnxAlyO2) Terhadap Struktur, Morfologi Dan Performa Ellektrokimia Baterai Ion Litium

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    Baterai ion litium merupakan perangkat sel elektrokimia yang memanfaatkan prinsip reaksi oksidasi dan reduksi untuk mengubah energi listrik menjadi energi kimia untuk menyimpan energi pada material katoda aktif. Baterai litium ion memiliki jenis katoda yang beragam, seperti katoda litium nikel mangan kobalt oksida, litium kobalt oksida dan yang lainnya. Berawal dari pengembangan baterai LiNiO2 yang memiliki kekurangan pada kemampuan mempertahankan kapasitasnya yang rendah, mangan dan kobalt diperkenalkan sebagai doping untuk mengurangi dampak degradasi tersebut. dikarenakan kobalt memiliki kekurangan pada ketersediaan dan harganya yang rendah, alternatif lain dibutuhkan untuk memenuhi kebutuhan. Aluminium yang memiliki kemiripan pada ukuran atom dilirik sebagai alternatif pengganti kobalt untuk mengurangi tingginya degradasi kapasitas baterai. Pada penelitian ini dilakukan sintesis katoda LiNi0,9MnxAlyO2 (Li-NMA) dengan variasi komposisi aluminium 1mol%, 3mol% dan 5mol%. Katoda disintesis dengan metode kopresipitasi pada larutan ion hidroksida dengan menggunakan amonia sebagai chelating agent, kemudian dilakukan kalsinasi dengan temperatur 750℃. Pengujian yang dilakukan yaitu dengan menggunakan metode X-Ray Diffraction, Scanning Electron Microscopy, Electrochemical Impedance, Cyclic voltametry dan SpectroscopyGalvanostatic Charge Discharge. Dari hasil penelitian tersebut diketahui penambahan aluminium efektif hingga pada 3mol% dengan naiknya rasio I(003)/I(104) sebesar 1,2009. Penambahan aluminium juga meningkatkan panjang kisi c dan penurunan dari ukuran kristal. Dari pengujian elektrokimia, diketahui penambahan aluminium hingga 3mol% memiliki pengaruh pada resistensi yang lebih rendah sebesar 219.7 Ω, jarak potensial reaksi oksidasi-reduksi yang lebih kecil sebesar 0.097V. hal ini menyebabkan katoda dengan variasi 3mol% memiliki kapasitas yang lebih besar dibandingkan variasi lainnya yaitu sebesar 8,72mAh g-1 dan mengalami degradasi kapasitas yang lebih kecil hingga 39,4% setelah 50 siklus. ========================================================================================================================================== The lithium ion battery is an electrochemical cell device that utilizes the principle of oxidation and reduction reactions to convert electrical energy into chemical energy to store energy in the active cathode material. Lithium ion batteries have various types of cathodes, such as lithium nickel manganese cobalt oxide cathodes, lithium cobalt oxide and others. Starting from the development of LiNiO2 batteries which have deficiencies in the ability to maintain their low capacity, manganese and cobalt are introduced as doping to reduce the impact of this degradation. Because cobalt has a lack of availability and low cost, other alternatives are needed to meet demand. Aluminum, which is similar in atomic size, is considered as an alternative to cobalt to reduce the high degradation of battery capacity. In this research, cathode synthesis of LiNi0,9MnxAlyO2 (Li-NMA) was carried out with various aluminum compositions of 1mol%, 3mol% and 5mol%. The cathode was synthesized by coprecipitation method in hydroxide ion solution using ammonia as a chelating agent, then calcination was carried out at a temperature of 750℃. The tests were carried out using the X-Ray Diffraction method, Scanning Electron Microscopy, Electrochemical Impedance, Cyclic Voltametry and Spectroscopy Galvanostatic Charge Discharge. From the results of this study it is known that the addition of aluminum is effective up to 3mol% with an increase in the ratio I(003)/I(104) of 1.2009. The addition of aluminum also increases the c lattice length and decreases the crystal size. From electrochemical tests, it is known that the addition of aluminum up to 3mol% has an effect on a lower resistance of 219.7 Ω, a smaller potential distance for the oxidation-reduction reaction of 0.097V. This causes the cathode with the 3mol% variation to have a larger capacity than the other variations, namely 8.72mAh g-1 and experience a smaller capacity degradation of up to 39.4% after 50 cycles

    Application of BiVO4 for the photoelectrocatalytic degradation of aromatic compounds

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    Cilj ovog rada bio je ispitati fotoelektrokemijska svojstva BiVO4 i BiVO4/rGO elektroda elektrokemijskim metodama karakterizacije, te odrediti djelotvornost fotoelektrokemijskog (PEC) elektrokemijskog (EC) i fotokatalitičkog (PC) procesa. Ispitivanja su provedena u otopinama 5-aminosalicilne kiseline i fenola masenih koncentracija 28 mg/L, salicilne kiseline masenih koncentracija 28 mg/L i 14 mg/L, te 0,1 M otopini NaCl. Cilj je bio utvrditi koja aromatska tvar pokazuje najveći stupanj razgradnje te odrediti kako pH, napona i koncentraciju utječu na brzinu razgradnje. Primjenom kronoamperometrije i linearne voltametrije pokazano je da se uz BiVO4/rGO elektrodu postiže veća djelotvornost razgradnje u odnosu na BiVO4 elektrodu. Utvrđeno je da najvjerojatnije dolazi i do ireverzibilnih promjena u rGO strukturi tijekom izvedbe PEC procesa. Metodom tekućinske kromatografije visoke djelotvornosti (HPLC) praćena je koncentracija tijekom razgradnje iz čega su određeni optimalni pH uvjeti za razgradnju pojedine aromatske molekule korištene u ovom radu. Osim toga utvrđeno je kako napon i koncentracija utječu na proces razgradnje.The main goal of this study was to investigate photoelectrochemical properties of BiVO4 and BiVO4/rGO electrodes by electrochemical methods of characterization, as well as, to determine efficiency of photoelectrochemical (PEC), electrochemical (EC) and photocatalytic process (PC). Electrodes were tested in 0,1 M aqueous solution of NaCl before and after PEC process. Degradation of salicylic acid, 5-aminosalicylic acid and phenol was carried out. The selected compounds were tested in order to find out which aromatic compound is most susceptible to degradation under certain conditions of pH, voltage and concetration. Chronoamperometry and linear sweep voltametry have shown that higher degradation efficacy is achieved by using BiVO4/rGO electrode compared to BiVO4 electrode. Results also indicate that irreversible changes of rGO structure take place during PEC procces. The decrease in concetration value during degradation process was monitored by high preformance liquid chromatography (HPLC). The obtain results indicate the optimal pH value for degradation of each aromatic compound used in this study. In addition, the influence of voltage and concentration on degradation proces was found

    Oxidgeträgerte kleine Platincluster und deren Interaktion mit Wasser

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    Die effiziente Nutzung von Ressourcen stellt eine der größten Herausforderungen der heutigen Zeit dar. Gerade die chemische Industrie birgt mit ihrem hohen Material- und Energiebedarf ein hohes Optimierungspotential. Katalysatoren und die damit verbundenen Prozesse können diese Bedarfe maßgeblich reduzieren. Während in Bezug auf die katalytischen Eigenschaften von Platin als Festkörper für die Wasserstoffgewinnung fundierte Kenntnisse vorliegen, ist der Sub-Nanometer-Bereich kleiner Platincluster noch weitestgehend unverstanden. Um diese Wissenslücke zu füllen, wurde in der vorliegenden Dissertation ein integriertes Vakuumsystem entwickelt und optimiert, mit welchem monodisperse Platincluster (m < 16.000 amu) auf zuvor in-situ präparierten Oberflächen deponiert und charakterisiert werden können. Die Substrate entsprachen dünnen Oxidschichten auf Silizium und Titan als Modellersatzsysteme für passivierte Photoabsorber, sodass sich Si/SiO₂- und Ti/TiO₂-Schichtsysteme ergaben. Auf diesen verunreinigungsfreien Oxiden wurden Platincluster Pt_n mit n = 1, 2, 6, 8, 9, 10, 13, 19 und 29 mit jeweils ca. 7 % einer Monolage homogen deponiert. Die Analyse der Proben erfolgte anschließend mittels temperatur-programmierter Desorption, Röntgen- und Ultraviolettphotoelektronenspektroskopie, sowie elektrochemischer Charakterisierung in saurer, wässriger Lösung. Es konnte gezeigt werden, dass sich die elektronische Struktur der Schichtsysteme durch die Platindeposition verändert. Gerade im Bereich der Bandlücke der dünnen Oxidschicht werden Zustände des Platins induziert, sodass sich die verbleibende Energielücke bis zur Fermikante von zuvor 3,1 eV für TiO₂ auf 1,3 eV (Pt₁) bis 0,3 eV (Pt₂₉) durch Variation der Clustergröße einstellen lässt. Diese Justierbarkeit konnte im Rahmen der elektrokatalytischen Wasserspaltung genutzt werden, um den optimalen Größenbereich eines Platinnanopartikels für die Wasserstoffbildungsreaktion (HER) zu ermitteln. Es wurde beobachtet, dass im Größenbereich um Pt₁₉ (ca. 1 nm Durchmesser) die höchste massenbezogene Aktivität erhalten wird. Diese liegt um etwa eine Größenordnung über der von deponierten Platinatomen. Werden lediglich die Oberflächenatome berücksichtigt, so ist die Aktivität anhand von Stromdichten aus der Cyclovoltametrie von Pt₁₉ auf TiO₂ 13x höher als die von deponierten Platinatomen und 5x höher als die Referenz einer ausgedehnten Platinoberfläche, wie sie derzeit technisch genutzt werden. Dies ermöglicht ein effizienteres Design von Katalysatorsystemen, auch über die Wasserstoffbildung hinaus

    The study of corrosion on additive-manufactured metals.

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    The purpose of this study was to investigate and compare the corrosion mechanisms between wrought and additive-manufactured (3D-printed) copper and stainless steel. The experimental procedure consisted of measuring the open circuit potential, electrochemical impedance spectroscopy, linear sweep voltammetry, Tafel analysis, surface topology, and scanning electron microscopy for each metal within salt water, tap water, sulfuric acid, and synthetic body fluid (excluding copper in synthetic body fluid). Overall, printed stainless steel was more corrosion-resistant than wrought stainless steel in tap water and synthetic body fluid based on OCP, LSV, and surface topology results. Additionally, printed copper was more corrosion-resistant than wrought copper in tap water and 0.5 M sulfuric acid. Thus, printed metals seem to resist corrosion more than their wrought versions in tap water only. Based on EIS results of stainless steel, printed stainless steel was found to be more corrosion-resistant than wrought stainless steel in only synthetic body fluid. Although kinetics data shows that printed stainless steel is more corrosion-resistant than wrought in tap water, both corrode at similar rates, so this conclusion may be overlooked. On average, printed and wrought 17-4PH stainless steel corroded the fastest in 0.5 M sulfuric acid, followed by synthetic body fluid, then salt water, and finally tap water. Stainless steel exhibited complete pitting corrosion in salt water and synthetic body fluid and experienced uniform (and partial uniform) corrosion in tap water and sulfuric acid. Based on EIS results of copper, printed copper was more corrosion-resistant than wrought copper in tap water. Although kinetics data supports that printed copper is more corrosion-resistant than wrought copper in salt water and sulfuric acid, both corrode at similar rates in both cases. Therefore, this conclusion can also be neglected. Printed and wrought copper corroded the fastest in 0.5 M sulfuric acid, followed by salt water, then tap water. Copper exhibited uniform (and partial uniform) corrosion in tap water, salt water, and 0.5 M sulfuric acid
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