Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms

• Mykola Borzenkov,
• Piersandro Pallavicini,
• Angelo Taglietti,
• Laura D’Alfonso,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98

• tested [53]. It was shown that gold-nanoshell-modified surfaces can effectively kill E. faecalis on silicone surfaces under NIR irradiation. Several bacterial strains (E. coli, Bacillus subtilis, Exiguobacterium sp. AT1b), deposited on surfaces precoated with nanoporous gold disks, were inactivated after

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

• approaches to modify a gold surface. However, only few techniques are capable of characterizing the formation of these monolayers on porous substrates. Here, we present a method to in situ monitor the adsorption and desorption of self-assembled monolayers on nanoporous gold by resistometry, using cysteine as

• resistometry. From the desorption peak related to the (111) surface of the structure, which is associated with a resistance change of 4.8%, an initial surface coverage of 0.48 monolayers of cysteine could be estimated. Keywords: L-cysteine; in situ resistometry; nanoporous gold; self-assembled monolayer (SAM

• ); 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

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

• . 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

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

• element for hydrogen-sensing applications [23]. The mechanical properties of nanoporous samples have been extensively studied in the literature, especially for the model system of nanoporous gold (npAu). Reports on potential-controlled creep [24], fracture [25] and strength [26] in npAu add to the list of

• on plasticity in nanoporous gold have pointed towards the surface tension (in units of energy per area) being the relevant capillary parameter for plastic deformation, rather than surface stress, which is only responsible for elastic contributions [47][48]. This is reflected in an asymmetric

• significant contribution of the dilatometric stress to the deformation in nanoporous palladium. Both stresses contribute to elastic and plastic deformation of the sample. An expression for the elastic component of the length changes in a nanoporous material, which has been introduced for nanoporous gold

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

• for nanoporous gold, which is caused by alterations in the atomic bindings in superficial atomic layers [19]. In conclusion, resistometry and dilatometry represent two efficient, independent methods to characterize the hydrogen concentration in nanoporous palladium. The volume expansion of nanoporous

Cantilever bending based on humidity-actuated mesoporous silica/silicon bilayers

• Christian Ganser,
• Gerhard Fritz-Popovski,
• Roland Morak,
• Parvin Sharifi,
• Benedetta Marmiroli,
• Barbara Sartori,
• Heinz Amenitsch,
• Thomas Griesser,
• Christian Teichert and
• Oskar Paris

Beilstein J. Nanotechnol. 2016, 7, 637–644, doi:10.3762/bjnano.7.56

• environments. The potential of mesoporous “hard” materials such as nanoporous gold [11] or mesoporous silica [12] for such purposes has recently been highlighted, where the basic idea is to utilize the adsorption-induced deformation of highly porous materials. The simplest way of fabricating an actuator based

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

• 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

• from the dealloying of Ag–Au alloy to form nanoporous gold, in which the concentration of HNO3 was rather high. For a dilute HNO3 solution, the chemical reaction that may take place is given as follows [31]: It is reported that the reaction is rather slow at HNO3 concentrations of less than 3.80 M (ca

Polymer blend lithography for metal films: large-area patterning with over 1 billion holes/inch²

• Cheng Huang,
• Alexander Förste,
• Stefan Walheim and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2015, 6, 1205–1211, doi:10.3762/bjnano.6.123

• such as glass or metal can also be used as substrates. For example iron was used as substrate for the fabrication of nanoporous gold mesoflower arrays, which served afterwards for surface-enhanced Raman scattering [23]. With the metal PBL technique it is possible to fabricate more than one billion

From lithium to sodium: cell chemistry of room temperature sodium–air and sodium–sulfur batteries

• Philipp Adelhelm,
• Pascal Hartmann,
• Conrad L. Bender,
• Martin Busche,
• Christine Eufinger and
• Juergen Janek

Beilstein J. Nanotechnol. 2015, 6, 1016–1055, doi:10.3762/bjnano.6.105

• group also investigated non-carbon electrodes, such as nanoporous gold or titanium carbide (TiC) [60][84]. Both materials are claimed to significantly improve the cycle performance compared to carbon electrodes due to a higher chemical stability towards lithium oxide species. On the other hand, the

Liquid fuel cells

• Grigorii L. Soloveichik

Beilstein J. Nanotechnol. 2014, 5, 1399–1418, doi:10.3762/bjnano.5.153

• high OCV (1.75) V and showed a very high peak power density (1.02 W/cm2 at 80 °C) [161]. A higher temperature improves the performance of the cathode but has little effect on the anode [161]. An electrocatalyst consisting of dealloyed nanoporous gold leaves demonstrated activities toward both hydrazine

• towards hydrolysis turned out to be more efficient catalysts than platinum. Thiourea, a known hydrogen evolution inhibitor, was also used as an additive to increase the coulombic efficiency [181]. Nanoporous gold electrodes prepared by extracting Ag from an AgAu alloy catalyze the oxidation of AB at a

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

• oxidation as a test reaction. In order to distinguish between structural effects (structure–activity correlations) and bimetallic/bifunctional effects, unsupported nanoporous gold (NPG) samples prepared from different Au alloys (AuAg, AuCu) by selective leaching of a less noble metal (Ag, Cu) were employed

• 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

• molecular O2 and to deposit stable adsorbed active oxygen species on the surface. The results are discussed in a comprehensive picture, in an attempt to combine both structural effects (“structure-activity correlations”) and the role of the second, less noble metal. Experimental Nanoporous gold sample

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

• ) enables fabrication of perfectly ordered 2-dimensional arrays of nanoporous gold nanoparticles. The dewetting of Au/Ag bilayers on the periodically prepatterned substrates leads to the interdiffusion of Au and Ag and the formation of an array of Au–Ag alloy nanoparticles. The array of alloy nanoparticles

• 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