In situ magnesiothermic reduction synthesis of a Ge@C composite for high-performance lithium-ion batterie anodes

• Ha Tran Huu,
• Ngoc Phi Nguyen,
• Vuong Hoang Ngo,
• Huy Hoang Luc,
• Minh Kha Le,
• Minh Thu Nguyen,
• My Loan Phung Le,
• Hye Rim Kim,
• In Young Kim,
• Sung Jin Kim,
• Van Man Tran and
• Vien Vo

Beilstein J. Nanotechnol. 2023, 14, 751–761, doi:10.3762/bjnano.14.62

• ][58]. In the first anodic process, the peaks at 0.30 and 0.56 V vs Li/Li+ correspond to the dealloying reaction of LixGe alloys. This multistep delithiation correlates to the stepwise alloying observed by the splitting of cathodic peaks in the following cycles. Compared to the signals in the first

• the formation of the SEI layer. In the first charge process, the plateau at 0.52 V vs Li/Li+ is attributed to the dealloying of LixGe. The long plateau from 0.65 to 0.25 V vs Li/Li+ illustrates the continuous irreversible SEI formation in the subsequent cycles. Meanwhile, the signal of SEI formation

Formation of nanoflowers: Au and Ni silicide cores surrounded by SiO_x branches

• Feitao Li,
• Siyao Wan,
• Dong Wang and
• Peter Schaaf

Beilstein J. Nanotechnol. 2023, 14, 133–140, doi:10.3762/bjnano.14.14

• instance, alloyed AuAg nanoparticles show a tunable LSPR peak by changing the Au/Ag ratio [30]. Also, through the leaching of the less noble element, such as Ag in AuAg nanoparticles, dealloying can yield porous Au nanosponges with excellent optical properties [31][32][33][34][35]. Thus, it is interesting

Combining physical vapor deposition structuration with dealloying for the creation of a highly efficient SERS platform

• Adrien Chauvin,
• Walter Puglisi,
• Damien Thiry,
• Cristina Satriano,
• Rony Snyders and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2023, 14, 83–94, doi:10.3762/bjnano.14.10

• complexity and the high cost of gold restrict its use in devices. Here, we report on a novel two-step approach that combines the deposition of a silver–aluminum thin film with dealloying to design and fabricate efficient SERS platforms. The magnetron sputtering technique was used for the deposition of the

• alloy thin film to be dealloyed. After dealloying, the resulting silver nanoporous structures revealed two degrees of porosity: macroporosity, associated to the initial alloy morphology, and nanoporosity, related to the dealloying step. The resulting nanoporous columnar structure was finely optimized by

• tuning deposition (i.e., the alloy chemical composition) and dealloying (i.e., dealloying media) parameters to reach the best SERS properties. These are reported for samples dealloyed in HCl and with 30 atom % of silver at the initial state with a detection limit down to 10−10 mol·L−1 for a solution of

Antimony deposition onto Au(111) and insertion of Mg

• Lingxing Zan,
• Da Xing,
• Abdelaziz Ali Abd-El-Latif and
• Helmut Baltruschat

Beilstein J. Nanotechnol. 2019, 10, 2541–2552, doi:10.3762/bjnano.10.245

• than that observed by us. We also observed a smaller peak C1 on a polycrystalline Au electrode. Therefore, this difference is probably due to the roughness of the Au(111) surface, resulting from repeated alloying and dealloying during the cycling to obtain stable voltammetry in [12]. Upon extension of

Adsorption and desorption of self-assembled L-cysteine monolayers on nanoporous gold monitored by in situ resistometry

• Elisabeth Hengge,
• Eva-Maria Steyskal,
• Rupert Bachler,
• Alexander Dennig,
• Bernd Nidetzky and
• Roland Würschum

Beilstein J. Nanotechnol. 2019, 10, 2275–2279, doi:10.3762/bjnano.10.219

• ); voltammetry; Findings Nanoporous gold, produced by selective etching of the less noble component of a AuAg master alloy (also known as dealloying), is a very promising material in many applications due to its three-dimensional nanoporous structure. Among many other technological applications as sensing [1][2

• water and the easy handling. The npAu substrate material was fabricated by electrochemically assisted dealloying of Ag75Au25. The alloy was prepared by arc melting, homogenized at 800 °C for 12 h under argon atmosphere, rolled to a sheet of 220 μm in thickness, annealed again at 600 °C for 1 h, and cut

• commercial Ag/AgCl reference electrode (saturated KCl with a 3 M KNO3 salt bridge), relative to which all potentials will be stated in the following. Whenever the cell electrolyte was changed, the setup was immersed in distilled water for several hours for rinsing. Dealloying was performed in 0.1 M HClO4

TiO₂/GO-coated functional separator to suppress polysulfide migration in lithium–sulfur batteries

• Ning Liu,
• Lu Wang,
• Taizhe Tan,
• Yan Zhao and
• Yongguang Zhang

Beilstein J. Nanotechnol. 2019, 10, 1726–1736, doi:10.3762/bjnano.10.168

• batteries. Keywords: dealloying; functional separator; lithium–sulfur batteries; TiO2/GO composite; Introduction The portability of handheld electronic products and successful realization of next-generation electric vehicles urgently require advanced energy storage devices with higher storage capacity and

• /GO-coated separator was introduced between the Li anode and sulfur cathode as a highly efficient polysulfide absorber. The TiO2/GO composite was prepared by dealloying, as reported elsewhere [35], and subsequent spray drying. It has been demonstrated that the utilization of the TiO2/GO composite

• , which guarantees the excellent cyclic stability and desirable rate performance of Li/S batteries. Figure 2a shows X-ray diffraction (XRD) patterns of the as-spun and as-dealloyed sample. The TiAl foil exhibits Al3Ti (JCPDS 65-2667) and Al (JCPDS 65-2869) phases. After dealloying, the specimen shows a

A Ni(OH)₂ nanopetals network for high-performance supercapacitors synthesized by immersing Ni nanofoam in water

• Donghui Zheng,
• Man Li,
• Yongyan Li,
• Chunling Qin,
• Yichao Wang and
• Zhifeng Wang

Beilstein J. Nanotechnol. 2019, 10, 281–293, doi:10.3762/bjnano.10.27

• provides a new idea for the synthesis of nanostructured Ni(OH)2 by a simple approach and ultra-low cost, which largely extends the prospect of commercial application in flexible or wearable devices. Keywords: dealloying; Ni nanofoam; Ni(OH)2 nanopetals; metallic glass; supercapacitor; Introduction

• . demonstrated a nickel hydroxide@nanoporous gold/Ni foam electrode, which was synthesized by electrodeposition of a Sn–Au alloy on nickel foam with subsequent dealloying of Sn and electrodepostion of Ni(OH)2 on the nanoporous gold/Ni foam [25]. Liu et al. created Ni(OH)2/Cu2O nanosheets on nanoporous NiCu alloy

• no report on the in situ synthesis of nickel hydroxide nanosheets on Ni nanofoam through a simple and environmentally friendly method. In the present work, we propose a simple and environmentally friendly two-step preparation, including the dealloying of Ni40Zr20Ti40 metallic glass in HF solutions

Hydrogen-induced plasticity in nanoporous palladium

• Markus Gößler,
• Eva-Maria Steyskal,
• Markus Stütz,
• Norbert Enzinger and
• Roland Würschum

Beilstein J. Nanotechnol. 2018, 9, 3013–3024, doi:10.3762/bjnano.9.280

• , Austria 10.3762/bjnano.9.280 Abstract The mechanical strain response of nanoporous palladium (npPd) upon electrochemical hydrogenation using an in situ dilatometric technique is investigated. NpPd with an average ligament diameter of approximately 20 nm is produced via electrochemical dealloying. A

• ][2][3], resistance [4][5][6], magnetic moment [5][7], optical transmission [8] and selective chemical transport [9] have been reported in recent years, apart from the mechanical properties described below. Dealloying, a selective dissolution process, has become an established technique to produce

• to a flawless coverage by the noble component prevents the etching process. After Erlebacher et al. delivered a full description of the dealloying process on an atomistic scale [10], the process itself has been extensively studied [11][12][13], while being used to prepare a broad variety of different

Controlling surface morphology and sensitivity of granular and porous silver films for surface-enhanced Raman scattering, SERS

• Sherif Okeil and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2018, 9, 2813–2831, doi:10.3762/bjnano.9.263

• ][55][56], and nanotransfer printing, which was used to build stacks of gold nanorods or nanowires [4]. The production of nanoporous metal films or particles through a dealloying process also emerged as an effective tool for the facile formation of a large number of SERS-active hot spots [57][58][59

Facile chemical routes to mesoporous silver substrates for SERS analysis

• Elina A. Tastekova,
• Alexander Y. Polyakov,
• Anastasia E. Goldt,
• Alexander V. Sidorov,
• Alexandra A. Oshmyanskaya,
• Irina V. Sukhorukova,
• Dmitry V. Shtansky,
• Wolgang Grünert and
• Anastasia V. Grigorieva

Beilstein J. Nanotechnol. 2018, 9, 880–889, doi:10.3762/bjnano.9.82

• long time in air. Mesoporous noble metals are mostly used as catalysts for high surface energy, gas sensor components, cell imaging mediators, etc. [5]. The most popular methods for mesoporous metal processing include acidic etching of bimetallic molts [6], electrochemical dealloying [7

Dealloying of gold–copper alloy nanowires: From hillocks to ring-shaped nanopores

• Adrien Chauvin,
• Cyril Delacôte,
• Mohammed Boujtita,
• Benoit Angleraud,
• Junjun Ding,
• Chang-Hwan Choi,
• Pierre-Yves Tessier and
• Abdel-Aziz El Mel

Beilstein J. Nanotechnol. 2016, 7, 1361–1367, doi:10.3762/bjnano.7.127

• for several metals and alloys including gold, copper, silver, gold–copper and gold–silver. We demonstrate that applying an electrochemical dealloying process to the gold–copper alloy nanowire arrays allows for transforming the hillocks into ring-like shaped nanopores. The resulting porous gold

• nanowires exhibit a very high roughness and high specific surface making of them a promising candidate for the development of SERS-based sensors. Keywords: copper; dealloying; gold; hillocks; nanoporous; Introduction Improvement in nanoscience involves fundamental evolution in the synthesis and

• dealloying process to Au–Cu alloy nanowires, one can synthesize nanoporous nanowires with a special morphology (Figure 1c) that cannot be obtained when dealloying Au–Cu nanowires with a smooth surface. Results and Discussion There are several factors that influence the nodular growth including the

In situ characterization of hydrogen absorption in nanoporous palladium produced by dealloying

• Eva-Maria Steyskal,
• Christopher Wiednig,
• Norbert Enzinger and
• Roland Würschum

Beilstein J. Nanotechnol. 2016, 7, 1197–1201, doi:10.3762/bjnano.7.110

• dealloying, an electrochemical etching process that removes the less noble component from a master alloy. The volume and electrical resistance of np-Pd are investigated in situ upon electrochemical hydrogen loading and unloading. These properties clearly vary upon hydrogen ad- and absorption. During cyclic

• reversible actuation clearly exceeds the values found in the literature, which is most likely due to the unique structure of np-Pd with an extraordinarily high surface-to-volume ratio. Keywords: dealloying; dilatometry; hydrogen storage; nanoporous palladium; resistometry; Findings The knowledge about the

• and catalysis [2]. One attractive method to produce nanostructured metals with macroscopic dimensions is dealloying, an (electro-)chemical process, which removes the less noble component from an alloy by selective etching [3]. Nanoporous palladium (np-Pd) produced by free corrosion [4] as well as

Formation of substrate-based gold nanocage chains through dealloying with nitric acid

• Ziren Yan,
• Ying Wu and
• Junwei Di

Beilstein J. Nanotechnol. 2015, 6, 1362–1368, doi:10.3762/bjnano.6.140

• 10% nitric acid. It was found that chains of Au nanocages were formed on the substrate surface during dealloying. When the concentration of HNO3 increased to 20%, the structures of nanocages were damaged and formed crescent or semi-circular shapes. The transfer process on the substrate surface was

• discussed. Keywords: dealloying; gold nanocage chains; nitric acid; solid substrate; Introduction Gold nanocages (Au NC) are a novel kind of nanostructure that possesses hollow interiors and porous shells [1][2][3]. Hollow metal nanostructures show unique physical and chemical characteristics with respect

• final Au NCs, which maybe limit their applications. The dealloying or selective deletion of Ag from Ag–Au alloys with oxidative etchants such as nitric acid or perchloric acid has been widely used to synthesize nanoporous gold (NPG) [18][19][20][21]. Moreover, Xia et al. employed Fe(NO3)3 and H2O2 as

Growth and morphological analysis of segmented AuAg alloy nanowires created by pulsed electrodeposition in ion-track etched membranes

• Ina Schubert,
• Loic Burr,
• Christina Trautmann and
• Maria Eugenia Toimil-Molares

Beilstein J. Nanotechnol. 2015, 6, 1272–1280, doi:10.3762/bjnano.6.131

• through the nitric acid treatment. This effect is ascribed to dealloying in AuAg alloy structures taking place through layer-by-layer dissolution of Ag atoms and diffusion of Au atoms onto the surface [57][58]. Due to a higher Au concentration in the Au-rich segments, a Au passivation layer on the surface

Synthesis, characterization, and growth simulations of Cu–Pt bimetallic nanoclusters

• Subarna Khanal,
• Ana Spitale,
• Nabraj Bhattarai,
• Daniel Bahena,
• J. Jesus Velazquez-Salazar,
• Sergio Mejía-Rosales,
• Marcelo M. Mariscal and
• Miguel José-Yacaman

Beilstein J. Nanotechnol. 2014, 5, 1371–1379, doi:10.3762/bjnano.5.150

• -like structures for the Cu–Pt system, and core–shell structures for Au–Pt and Ag–Pt. Yu et al. [35] investigated the formation of and dealloying of CuPt bimetallic nanoparticles in presence of hexadecylamine or PVP as capping agents, obtaining different morphologies of nanoparticles depending on their

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

• charge coefficient in this regime (Figure 4b). It is worth mentioning that, compared to the present case of cluster-assembled porous Pt, the charge-induced resistance variation of nanoporous Pt prepared by electrochemical dealloying in addition showed a sign inversion at high potentials [7]. This

• different behavior has to be assigned to the strongly different types of surface states originating from the preparation, which is a chemical reduction process for the commercial Pt powder, whereas dealloying takes place under strongly oxidizing conditions. In fact, as shown by Viswanath et al. [18

Catalytic activity of nanostructured Au: Scale effects versus bimetallic/bifunctional effects in low-temperature CO oxidation on nanoporous Au

• Lu-Cun Wang,
• Yi Zhong,
• Haijun Jin,
• Daniel Widmann,
• Jörg Weissmüller and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2013, 4, 111–128, doi:10.3762/bjnano.4.13

• , whose structure (surface area, ligament size) as well as their residual amount of the second metal were systematically varied by applying different potentials for dealloying. The structural and chemical properties before and after 1000 min reaction were characterized by scanning electron microscopy (SEM

• latter method, electrochemical dealloying, nanoporous gold (NPG) materials with ligament sizes of less than 6 nm can be effectively fabricated [5][10]. Zielasek et al. [4] and Xu et al. [11] reported that nanoporous gold, prepared by the selective dissolution of Ag from a AuAg alloy, exhibits a

• amounts of the second, less noble metal in the Au alloy used for NPG formation, such as Ag [13][29][30], Cu [6] or Al [31], which cannot be fully removed during dealloying [29], were proposed to be responsible for the unexpected high catalytic activity of NPG catalysts [4][32][33]. This would agree also

Ordered arrays of nanoporous gold nanoparticles

• Dong Wang,
• Ran Ji,
• Arne Albrecht and
• Peter Schaaf

Beilstein J. Nanotechnol. 2012, 3, 651–657, doi:10.3762/bjnano.3.74

• , 85748 Garching, Germany Center for Micro- and Nanotechnologies, Ilmenau University of Technology, POB 10 05 65, 98684 Ilmenau, Germany 10.3762/bjnano.3.74 Abstract A combination of a “top-down” approach (substrate-conformal imprint lithography) and two “bottom-up” approaches (dewetting and dealloying

• is transformed into an array of nanoporous gold nanoparticles by a following dealloying step. Large areas of this new type of material arrangement can be realized with this technique. In addition, this technique allows for the control of particle size, particle spacing, and ligament size (or pore

• size) by varying the period of the structure, total metal layer thickness, and the thickness ratio of the as-deposited bilayers. Keywords: dealloying; dewetting; nanoimprint lithography; nanoparticles; nanoporous gold; ordered arrays; Introduction Metallic nanoparticle arrays are attracting more and