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Daneshpazhoonejad, Farshad; Shekhawat, Deepshikha; Döll, Joachim; Pezoldt, Jörg; Jung, Anne
Simulation of heat transfer and propagation velocity for different heat loss conditions for guided propagation fronts in reactive multilayer foils. - In: Advanced engineering materials, ISSN 1527-2648, Bd. 0 (2024), 0, 2400523, S. 1-9

Engineering self-propagating reactions in reactive material systems requires an understanding of critical ignition and propagation conditions. These conditions are governed by the material properties of the reactive materials responsible for net heat generation, as well as by external environmental conditions that primarily determine net heat loss. In this study, it is aimed to utilize a numerical model to investigate the critical conditions for reaction propagation based solely on the heat-transfer equation, enabling thorough examination with significantly low computational effort. Comparing simulations with experiments demonstrates a high level of agreement in predicting reaction propagation. Additionally, this numerical model provides valuable information regarding heat distribution in substrate materials.

Vereecken, Philippe; Vasiljevic, Natasa; Magagnin, Luca; Zheng, J. X. Kent; Leimbach, Martin
A bright future for electrodeposition. - In: The Electrochemical Society interface, ISSN 1944-8783, Bd. 33 (2024), 2, S. 45-46

The Electrodeposition Division, which was founded in 1922 as the second ECS division, celebrated their centennial anniversary at the 242nd ECS Fall meeting in Atlanta. For the occasion, the division organized several sessions with invited contributions to honor the achievements of 100 years of electrodeposition, but also to take a closer look at the present trendsetters and give a perspective on future challenges and opportunities in this thriving field. Our then newly established Electrodeposition Early Career Forum (ECF, founded in Spring 2022) organized a full day symposium with contributions from outstanding early-career researchers involved in cutting-edge research across a broad range of areas of active electrodeposition research. It turned out to be a fantastic day with invigorating talks full of ideas. The ELDP division decided to share some of the excitement with the ECS community and asked our ECF members to suggest topics and participate in the articles for this summer edition of Interface dedicated to Electrochemical and Electroless deposition. Dr. Kent Zheng, assistant professor at the University of Texas and Dr. Martin Leimbach, postdoc at TU Ilmenau, Germany, took up the challenge. Together with us, humble guest editors, four articles have been selected centred around three important topics: (1) electrodeposition for manufacturing and sustainability, edited by Prof. Luca Magagnin; (2) electrodeposition for energy applications, edited by Prof. Natasa Vasiljevic; and (3) new electrodeposition approaches extending the material library, edited by Prof. Philippe Vereecken.

Badalbayli, Anar; Sinclair, Nicolas; Bernasconi, Roberto; Borisenko, Natalia; Venkatesh, Krishna; Ispas, Adriana; Akolkar, Rohan; Magagnin, Luca
Advancements in electrodeposition for precise manufacturing and sustainability. - In: The Electrochemical Society interface, ISSN 1944-8783, Bd. 33 (2024), 2, S. 47-54

Simply expressed, the circular economy implies that the people living on Earth should reuse and recycle the products that are currently in use as long as possible and reduce the waste produced, thus reducing CO2 emissions. The latter goal is fundamental from the perspective of mitigating the well-known greenhouse effect and the consequent global warming observed at the planetary scale. Under these conditions, advanced electrodeposition processes can play a fundamental role in the optimization of materials use and in the reduction of the energetic footprint for a wide variety of industrial processes. The aim of the present paper is precisely to suggest how this is possible, showing readers the potential that electrodeposition holds for efficient manufacturing of many different products that have a huge significance for industry.

Yan, Yong; Li, Tongxian; Oliva Ramírez, Manuel; Zhao, Yuguo; Wang, Shuo; Chen, Xin; Wang, Dong; Schaaf, Peter; Wang, Xiayan; Guo, Guangsheng
Efficient tuning of the selectivity of Cu-based interface for electrocatalytic CO2 reduction by ligand modification. - In: Materials today, ISSN 2468-6069, Bd. 44 (2024), 101620, S. 1-12

The development of efficient strategies to tune the CO2RR selectivity of Cu-based catalytic interfaces, especially on specific domains, such as Cu (200) facets with high activity toward competitive hydrogenation evolution reaction (HER), remains a challenging task. In this work, Cu-based catalytic layers with thiocyanate (-SCN), cyanide (-CN), or ethylenediamine (-NH2R) coordination linkages are prepared on Cu nanocolumns arrays (Cu NCAs) with predominant (200) exposed facets. The coordination of these ligands induces more Cu+ species and inhibits the adsorption of H∗ on the Cu (200) facet, leading to enhanced CO2RR performance and substantially suppressing the competitive HER. The faradaic efficiency (FE) of Cu–SCN, Cu–CN, and Cu–NH2R NWAs for producing HCOOH, C2H4, and C1 mixture products (HCOOH and CO) reach to 66.5%, 21.1%, and 57.1%, respectively. In situ spectroscopic studies reveal Cu–SCN, Cu–CN, and Cu–NH2R exhibit more reasonable adsorption energy toward ∗OCHO, ∗CO, and ∗COOH intermediates, promoting the HCOOH, C2H4, and C1 mixture generation, respectively. This study might provide a new perspective for the development of high-performance Cu-based CO2RR catalytic electrodes based on the combination of various commercial free-standing Cu substrates and organic/inorganic ligands.

Elkholy, Hagar S.; Herrmann, Andreas; Othman, Hosam A.
The effect of zinc substitution on the optical properties of Sm3+ doped zinc borate glasses. - In: Optical materials, ISSN 1873-1252, Bd. 154 (2024), 115606, S. 1-19

Zinc borate glasses are a relatively well known glass type that can be produced at comparably low temperatures. Variations in both the type and concentration of network modifier atoms induce structural alterations within the glass matrix. If doped with optically active dopants, e.g. rare earth ions, compositional changes also affect the local surrounding of the dopants and consequently their optical properties such as emission peak shape and peak ratio. To investigate the effect of different low field strength network modifier ions in zinc borate glasses two glass series were prepared using the melt quench technique; Sm3+ was used as dopant ion: 50B2O3, xK2O, (49-x)ZnO, 1Sm2O3 (x = 5,10,15, …, 30 mol%) and 50B2O3, 30MO, 19ZnO, 1Sm2O3 (M = Ca, Sr and Ba). It is found that the substitution of ZnO for K2O notably enhances the intensity of the red Sm3+emission. Based on the literature this effect is attributed to a change in symmetry at the rare earth position. Additionally, the effect of network modifier concentrations and the different network modifier types on the Sm3+ absorption spectra is examined, discussed and compared to literature data. Furthermore, the glasses are characterized according to their density, refractive index, molar volume, and oxygen packing density.

Gholami-Kermanshahi, Mozhgan; Lee, Ming-Cheng; Lange, Günther; Chang, Shih-Hang
Effects of N2 plasma modification on the surface properties and electrochemical performance of Ni foam electrodes for double-chamber microbial fuel cells. - In: Materials advances, ISSN 2633-5409, Bd. 5 (2024), 13, S. 5554-5560

This study assessed the feasibility of using a plasma-modified Ni foam as an anode to improve the electrochemical performance of double-chamber microbial fuel cells (MFCs). Scanning electron microscopy results showed that Ni foam exhibited an open cellular structure and rough surface morphology, providing a large contact area between bacteria and anodes in the MFCs. N2 plasma modification did not influence the surface morphology of the Ni foam, whereas the hydrophobic surfaces of the Ni foam became highly hydrophilic. X-ray photoelectron spectrometer results revealed that Ni-N and NH3 functional groups, formed on the surface of the Ni foam during the N2 plasma modification, were responsible for its highly hydrophilic surface. Electrochemical measurements demonstrated that the highest power density of the MFC configured with an unmodified Ni foam anode electrode (166.9 mW m−2) was much higher than those of the MFCs configured with dense Ni rod (5.1 mW m−2) or graphite rod (29.5 mW m−2) anodes because Ni foam combined the advantages of an open cellular structure and good electrical conductivity. The highest power density of MFC configured with Ni foam was further improved to 247.1 mW m−2 after 60 min N2 plasma treatment owing to the high hydrophilicity of the N2 plasma-modified Ni foam electrodes, which facilitated bacteria adhesion and biofilm formation.

Sauni Camposano, Yesenia Haydee; Jaekel, Konrad; Riegler, Sascha S.; Matthes, Sebastian; Glaser, Marcus; Peter, Nicolas J.; Vardo, Emina; Bartsch, Heike; Schwaiger, Ruth; Bergmann, Jean Pierre; Gallino, Isabella; Schaaf, Peter
Controlling propagation velocity in Al/Ni reactive multilayer systems by periodic 2D surface structuring. - In: Advanced engineering materials, ISSN 1527-2648, Bd. n/a (2024), n/a, 2302272, S. 1-11

The chemical energy released as heat during the exothermic reaction of reactive multilayer systems has shown potential applications in various technological areas, e.g., in joining applications. However, controlling the heat release rate and the propagation velocity of the reaction is required to enhance their performance in most of these applications. Herein, a method to control the propagation velocity and heat release rate of the system is presented. The sputtering of Al/Ni multilayers on substrates with periodic 2D surface structures promotes the formation of growth defects into the system. This modification in the morphology locally influences the reaction characteristics. Tailoring the number of 2D structures in the substrate enables the control of the velocity and maximum temperature of the propagation front. The morphology of the produced reactive multilayers is investigated before and after reaction using scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. In addition, the enthalpy of the system is obtained through calorimetric analysis. The self-sustained and self-propagating reaction of the systems is monitored by a high-speed camera and a high-speed pyrometer, thus revealing the propagation velocity and the temperatures with time resolution in the microsecond regime.

Graske, Marcus; Sauni Camposano, Yesenia Haydee; Vardo, Emina; Matthes, Sebastian; Schaaf, Peter
Mechanical ignition of Al/Ni reactive multilayer systems: influence of impacting material, its properties, and geometric characteristics. - In: Advanced engineering materials, ISSN 1527-2648, Bd. n/a (2024), n/a, 2400479, S. 1-13

Al/Ni reactive multilayer systems (RMS) with a bilayer thickness of Λ = 50 nm and total thickness th = 5 μm on a SiO2 substrate exhibit a self-propagating reaction after ignition. A common method to initiate the self-propagating reaction is by electric spark ignition. Herein, RMS are ignited by a mechanical impact using various materials with indeterminate geometries to investigate the basic mechanisms. SiO2, glass, PMMA, and resin-bonded SiC particles are used as impacting material with different geometrical impact areas. The used materials are placed on top of the RMS and a mechanical impulse is applied. The ignition behavior of the RMS is subsequently evaluated and classified. Additionally, the impacted RMS are examined by microscopy to reveal the damage pattern. By correlating particle size ⟨Dparticle⟩ and spacing ⟨dhole⟩ of the penetrating materials, an ignition threshold can be established. Moreover, the results demonstrate that the energy input threshold can be reduced through a strategic distribution of particles within the impacting and penetrating geometry. This provides valuable insights into the mechanical ignition fundamental and supports future applications of mechanical ignition of RMS.

Moreira, Pedro H. O.; Soydan, Alper K.; Reiprich, Johannes; Isaac, Nishchay Angel; Aliabadian, Bardia; Vernizzi, Guilherme J.; Jacobs, Heiko O.
Patterned liquid micro rails for the transport of micrometer sized chips. - In: Advanced Materials Technologies, ISSN 2365-709X, Bd. n/a (2024), n/a, 2400235, S. 1-11

Transport and alignment of microscopic chips are important steps in microelectronics component integration with common approaches being pick-and-place, microfluidics, parallel transfer and self-assembly. An alternate transport approach of microscopic chips is proposed using patterned liquid micro rails as chaperones. The surface free energy and interfacial free energy minimization of all constituents enable the creation of stable pathways. This allows for chip-attachment to rails, while the liquid layer lubricates chip-sliding. Monorails, digital monorails, and digital birails are investigated for chip movement behavior. Chip position and speed can be controlled using liquid flow in closed chambers. Speeds from 10 to 400 mm s−1 are achieved with translation distances as long as 50 mm. It is discovered that chips can selectively cross rail discontinuities of up to 500 µm, allowing for chip position control through a stop-and-go motion. A programmable liquid rails-based chip conveyor system is demonstrated by transporting diodes to receptor sites where they undergo self-assembly.

Wang, Honglei; Cheng, Pengfei; Wu, Bing; Yan, Yong; Schaaf, Peter; Sofer, Zdeněk; Wang, Dong
2D metal phosphorous trichalcogenides (MPCh3) for sustainable energy storage and conversion: nanoarchitectonics and advanced applications. - In: Advanced functional materials, ISSN 1616-3028, Bd. n/a (2024), n/a, 2407432, S. 1-22

2D metal phosphorous trichalcogenides (MPCh3) have attracted considerable attention in sustainable energy storage and conversion due to their distinct physical and chemical characteristics, such as adjustable energy bandgap, significant specific surface area, and abundant active sites. However, research on 2D MPCh3 primarily focuses on electrocatalysis, and understanding its energy conversion and storage mechanisms remains incomplete. This review comprehensively summarizes recent advancements in energy storage and conversion using 2D MPCh3-based materials of various structures. It begins with a discussion of the distinctive properties and preparation techniques of 2D MPCh3, followed by a focus on the rational design and development of these materials for diverse energy-related applications, including rechargeable batteries, supercapacitors, electrocatalysis, photocatalysis, and desalination. Finally, it outlines the key challenges and prospects for future research on 2D MPCh3 materials.