Design criteria for stable Pt/C fuel cell catalysts

• Josef C. Meier,
• Carolina Galeano,
• Ioannis Katsounaros,
• Jonathon Witte,
• Hans J. Bongard,
• Angel A. Topalov,
• Claudio Baldizzone,
• Stefano Mezzavilla,
• Ferdi Schüth and
• Karl J. J. Mayrhofer

Beilstein J. Nanotechnol. 2014, 5, 44–67, doi:10.3762/bjnano.5.5

• ] reported that such transitions in potential result in more severe catalyst surface area losses compared to constantly high potentials. These drastic conditions, which can be simulated in electrochemical half-cell experiments by, e.g., subjecting the catalyst to cyclic voltammetry, are a demanding challenge

Some reflections on the understanding of the oxygen reduction reaction at Pt(111)

• Ana M. Gómez-Marín,
• Ruben Rizo and
• Juan M. Feliu

Beilstein J. Nanotechnol. 2013, 4, 956–967, doi:10.3762/bjnano.4.108

• was attributed to sulfate adsorption, while taking into account voltammetry and XPS experiments [68]. Recently, the problem was raised by Markovic et al. at the Argonne National Laboratory and it was considered to be because of metals like Ni, Co and Fe [69]. In our experiments, we have found these

Synthesis and electrochemical performance of Li₂Co_1−xM_xPO₄F (M = Fe, Mn) cathode materials

• Nellie R. Khasanova,
• Oleg A. Drozhzhin,
• Stanislav S. Fedotov,
• Darya A. Storozhilova,
• Rodion V. Panin and
• Evgeny V. Antipov

Beilstein J. Nanotechnol. 2013, 4, 860–867, doi:10.3762/bjnano.4.97

• voltammetry supported a single-phase de/intercalation mechanism in the Li2Co0.9Mn0.1PO4F material. Keywords: energy related; fluorophosphates; high-energy cathode materials; high-voltage electrolyte; Li-ion batteries; nanomaterials; reversible capacity; Introduction In recent years the range of application

• voltammetry to further establish their compatibility with high-voltage cathode materials. Two types of working electrodes were used to evaluate the electrochemical window of the electrolytes: 1) Al-foil (since it is used as a current collector for the positive electrode); 2) an “idle electrode”, which

• voltammetry scanning was performed in the voltage range of 2.5–5.5 V at a scan rate of 0.1 mV·s−1. The galvanostatic charge–discharge cycling was conducted in the voltage range of 2.5–5.5 V at a rate of C/5 (the current required to deintercalate one Li ion from Li2Co1-xMxPO4F in 5 hours). Crystal structure of

Optimization of solution-processed oligothiophene:fullerene based organic solar cells by using solvent additives

• Gisela L. Schulz,
• Marta Urdanpilleta,
• Roland Fitzner,
• Eduard Brier,
• Elena Mena-Osteritz,
• Egon Reinold and
• Peter Bäuerle

Beilstein J. Nanotechnol. 2013, 4, 680–689, doi:10.3762/bjnano.4.77

• of the molar extinction coefficient, saturated solutions were made, stirred for 60 min at 60 °C then allowed to cool to room temperature. The saturated solution was then filtered and diluted for absorption spectroscopy, and the corresponding concentration could be determined. Cyclic voltammetry

• properties of DCV5T-Bu4 were probed by using cyclic voltammetry, the results of which are plotted in Figure 1b and summarized in Table 1. Measurements were performed in dichloromethane solutions containing tetrabutylammonium hexafluorophosphate (TBAPF6) and referenced against the internal ferrocene

Preparation of electrochemically active silicon nanotubes in highly ordered arrays

• Tobias Grünzel,
• Young Joo Lee,
• Karsten Kuepper and
• Julien Bachmann

Beilstein J. Nanotechnol. 2013, 4, 655–664, doi:10.3762/bjnano.4.73

• in a Li+-containing electrolyte. The cyclic voltammetry of the lithium/silicon system is typically characterized by a sharp reduction between +0.1 and +0.2 V (vs Li/Li+) on the charging curve and a broader double oxidation peak situated between +0.3 and +0.7 V upon discharge [6][7][8]. Upon inclusion

• arrows. Cyclic voltammetry recorded on a silicon nanotube sample at 0.1 mV s−1 in 1 mol L−1 LiPF6 in ethylene carbonate/dimethylcarbonate by using metallic lithium as the auxiliary electrode and pseudo-reference. The scans were performed between +3.25 V and +0.05 V. The first cycle is plotted as a thin

Ultramicrosensors based on transition metal hexacyanoferrates for scanning electrochemical microscopy

• Maria A. Komkova,
• Angelika Holzinger,
• Andreas Hartmann,
• Alexei R. Khokhlov,
• Christine Kranz,
• Arkady A. Karyakin and
• Oleg G. Voronin

Beilstein J. Nanotechnol. 2013, 4, 649–654, doi:10.3762/bjnano.4.72

• . Three types of UME were used: (i) carbon, (ii) platinum and (iii) platinum covered with an ion beam induced deposition (IBID)-generated Pt/C composite material [28]. Deposition of PB was carried out by using cyclic voltammetry (CV) as described elsewhere in detail [29]. PB was deposited using 5 cycles

• ratio of carbon to platinum in the range of 60 atom % C to 24 atom % Pt [28]. Cyclic voltammetry, optical microscopy, and AFM (5500 AFM, Agilent Technologies) imaging were performed for characterizing the fabricated microelectrodes. The deposition of PB was carried out as described in detail elsewhere

• of 100 mV/s applying 20 scans. After the deposition of NiHCF, the electrodes were rinsed with MilliQ water (Millipore MilliQ system) and and tempered at 80 °C for 0.5 h. The deposition of the mixed films was performed as follows. First, a layer of PB was deposited by cyclic voltammetry as described

Novel composite Zr/PBI-O-PhT membranes for HT-PEFC applications

• Mikhail S. Kondratenko,
• Igor I. Ponomarev,
• Marat O. Gallyamov,
• Dmitry Y. Razorenov,
• Yulia A. Volkova,
• Elena P. Kharitonova and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2013, 4, 481–492, doi:10.3762/bjnano.4.57

• were examined by means of SAXS, thermomechanical analysis (TMA), and were tested in operating fuel cells by means of stationary voltammetry and impedance spectroscopy. The new membranes showed excellent stability in a 2000-hour fuel cell (FC) durability test. The modification of the PBI-O-PhT films

In situ monitoring magnetism and resistance of nanophase platinum upon electrochemical oxidation

• Eva-Maria Steyskal,
• Stefan Topolovec,
• Stephan Landgraf,
• Heinz Krenn and
• Roland Würschum

Beilstein J. Nanotechnol. 2013, 4, 394–399, doi:10.3762/bjnano.4.46

• relative to Ag/AgCl. As reference values for the resistance and the magnetic moment, the initial values R0 and m0 of the respective measurement were used. Results Charging was performed by the electrochemical methods of cyclic voltammetry, with a constant scan rate of 0.5 mV/s, or chronoamperometry (CA

• resistance variation were found by chronoamperometry and cyclic voltammetry. The combination of SQUID magnetometry and in situ cyclic voltammetry opens up attractive potentials for studying nanophase materials under full electrochemical control. Steady-state cyclic voltammograms (CVs) of porous

Electrospinning preparation and electrical and biological properties of ferrocene/poly(vinylpyrrolidone) composite nanofibers

• Ji-Hong Chai and
• Qing-Sheng Wu

Beilstein J. Nanotechnol. 2013, 4, 189–197, doi:10.3762/bjnano.4.19

• model organisms. The nanofibers fabricated by this method showed obvious antibacterial activity. Electrochemical properties were characterized based on cyclic voltammetry measurements. The CV results showed redox peaks corresponding to the Fc+/Fc couple, which suggested that Fc molecules encapsulated

Revealing thermal effects in the electronic transport through irradiated atomic metal point contacts

• Bastian Kopp,
• Zhiwei Yi,
• Daniel Benner,
• Fang-Qing Xie,
• Christian Obermair,
• Thomas Schimmel,
• Johannes Boneberg,
• Paul Leiderer and
• Elke Scheer

Beilstein J. Nanotechnol. 2012, 3, 703–711, doi:10.3762/bjnano.3.80

• potential origin of the light-induced signals. To check this hypothesis, cyclic voltammetry was performed at different temperatures by directly heating up the whole setup in a stove. Cyclic voltammograms (CVs) recorded at 45 and 35 °C are shown in Figure 5, which indicates that the redox peak shifted to

• drop across the series resistance. This signal, as well as the voltage drop Usample across the sample are measured with fast voltage amplifiers (Femto DLPVA-100-F-D). All signals are fed to a digital storage oscilloscope (LeCroy Waverunner 6050A). Cyclic voltammetry The cyclic voltammograms were

• was heated in a stove for five minutes at a preset temperature, monitored by a thermocouple to a precision of ± 2 °C. Then the cyclic voltammetry was performed in situ. A home-made electrochemical setup (as shown in Figure 13) was used to investigate the light-induced transport changes in the liquid

Glassy carbon electrodes modified with multiwalled carbon nanotubes for the determination of ascorbic acid by square-wave voltammetry

• Sushil Kumar and
• Victoria Vicente-Beckett

Beilstein J. Nanotechnol. 2012, 3, 388–396, doi:10.3762/bjnano.3.45

• voltammetry (SWV). The oxidation of ascorbic acid at the modified glassy carbon electrode showed a peak potential at 315 mV, about 80 mV lower than that observed at the bare (unmodified) electrode. The peak current was about threefold higher than the response at the bare electrode. Replicate measurements of

• no significant difference (P = 0.05). Keywords: ascorbic acid; carbon nanotubes; glassy carbon electrode; square-wave voltammetry; Introduction L-ascorbic acid (AA), also known as vitamin C, is a well-known antioxidant, which helps the human body to reduce oxidative damage and protects food quality

• expensive. The spectrophotometric method suffers from poor selectivity due to interference from other compounds present in commercial fruit juices (e.g., sugars or glucuronic acid) while citrate may affect enzymatic methods [7]. Electrochemical techniques, particularly cyclic voltammetry (CV) and square

The atomic force microscope as a mechano–electrochemical pen

• Christian Obermair,
• Andreas Wagner and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2011, 2, 659–664, doi:10.3762/bjnano.2.70

• , simultaneously the passivation layer is partially removed, site-selectively, with the tip of an AFM. The appropriate electrochemical potential is determined by cyclic voltammetry, and a cathodic potential is selected so as to be too low to lead to an overall growth of the metal film in spite of the passivation

Electrochemical behavior of dye-linked L-proline dehydrogenase on glassy carbon electrodes modified by multi-walled carbon nanotubes

• Haitao Zheng,
• Leyi Lin,
• Yosuke Okezaki,
• Ryushi Kawakami,
• Haruhiko Sakuraba,
• Toshihisa Ohshima,
• Keiichi Takagi and
• Shin-ichiro Suye

Beilstein J. Nanotechnol. 2010, 1, 135–141, doi:10.3762/bjnano.1.16

• long-time ultrasonication (30 min) used. Electrochemical behavior of L-proDH on MWCNTs–modified GC electrode The electrochemical properties of GC/MWCNTs were first investigated by cyclic voltammetry with K3Fe(CN)6 as the probe. Typical reversible cyclic voltammograms were observed for both the bare and