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The effects of electromagnetic (EM) radiation have received increased attention, closely associated with the widespread use of electronics and wireless communication. A significant development in the area is the recent adoption of metal‐organic frameworks (MOFs) to effectively enable electromagnetic interference (EMI) shielding. MOF tunable molecular scaffold architecture offers numerous pathways to generate customizable magnetic and electrical properties, which are prerequisite materials characteristics for efficient EMI shielding performance. Their flexibility in terms of structural design, accompanied by high porosity and large specific surface area, makes MOFs excellent candidates to shield EM waves at multiple scales. Herein, the crucial role of molecular‐, nano‐, micro‐, and macro‐scale structural design is reviewed in accordance with the shielding performance of MOFs. The current design strategies of MOF‐based EMI shields are systematically outlined, and the shielding mechanisms are also expounded based on their structural features. The factors that hinder the widespread utilization of functional MOF‐derived EMI shields are also examined. Future research directions are unveiled for the rational design of the next‐generation MOF‐based EMI shields to address the pressing EM radiation concerns. [ABSTRACT FROM AUTHOR]

Ferroelectric materials hold significant potential for ultralow-energy-consuming oxide electronics and have recently been pointed out as a suitable platform for next-generation neuromorphic and reservoir computing schemes. We provide a brief overview of the progress in engineering electric dipole textures of epitaxial ferroelectric oxide thin films, with an emphasis on the technologically relevant ultrathin regime. In epitaxial films that are only a few unit-cells thick, surface chemistry and interfacial electrostatics are commonly considered limiting factors in ferroelectric device integration, as they may suppress the net ferroelectric behavior. Here, we highlight how nanoscale lattice chemistry control, including off-stoichiometry and layer polarization in oxides, can, in fact, emerge as powerful tools for engineering ferroelectricity in thin films. We also discuss the potential of such an approach in the context of recent trends in the field, such as the design of ferroelectric freestanding membranes and the optical control of polarization in thin films. Hence, with our Perspective article, we aim to provide key insights on the use of lattice chemistry for ferroelectricity engineering in thin films to facilitate exciting developments in ferroelectric-based applications. [ABSTRACT FROM AUTHOR]

Referring to selected examples of reproducible green syntheses using hybrid sol‐gel catalysts of the SiliaCat series from different doctoral theses and research works published between 2015 and early 2024, this study briefly illustrates how said catalysts have been applied in a number of green synthetic methods of significant industrial relevance. This shows evidence that the nanochemistry "bottom‐up" sol‐gel approach based on catalytic species entrapped in organically modified silicas as effective and versatile heterogeneous catalysts developed between the late 1990s and 2010 has succeeded. Subsequent developments will show how the use of said materials in automated syntheses, supplying data to machine learning algorithms actually leads to faster and cheaper optimization of the reaction conditions. Said progress ultimately will further accelerate industrial uptake of heterogeneous catalysis under flow in the fine chemical industry whose reluctance to change processes was due to the need to replace financially amortized (and expensive) production plants. [ABSTRACT FROM AUTHOR]

This article provides information on the integration of nanochemistry into secondary education curricula in Lower Saxony, Germany. It discusses the Nan_OS school laboratory setting, which aims to teach students about the properties, applications, opportunities, and risks of nanochemistry. The article also presents three innovative experiments that can be used in secondary education to introduce students to the synthesis and applications of nanoparticles. It emphasizes the importance of adapting school curricula to reflect current research and developments in nanotechnology and highlights the need for further development of experiments in the field of nanochemistry to support teachers in creating research-based lesson plans. [Extracted from the article]

Since 2012, the National Nanoscience Teaching and Training Platform (NNPTTP), funded by the South African Department of Science and Innovation (DSI), has been responsible for overseeing Africa's first-ever master's in nanoscience program. For over a decade, the NNPTTP has seen the cooperation of four partner universities across South Africa, namely, the University of Johannesburg (UJ), University of the Free State (UFS), University of the Western Cape (UWC), and Nelson Mandela University (NMU), culminating in over 250 graduates trained in either nanophysics, nanochemistry, or nanobiology. Originally established to train professionals for a nanotechnology-based industry, both in South Africa and internationally, the program and platform has evolved into a testament to scientific collaboration. This paper discusses the program's framework, successes and challenges, related research, and future plans. [ABSTRACT FROM AUTHOR]

Advancements in nanochemistry have led to the development of engineered gold nanostructures (GNSs) with remarkable potential for a variety of dental healthcare applications. These innovative nanomaterials offer unique properties and functionalities that can significantly improve dental diagnostics, treatment, and overall oral healthcare applications. This review provides an overview of the latest advancements in the design, synthesis, and application of GNSs for dental healthcare applications. Engineered GNSs have emerged as versatile tools, demonstrating immense potential across different aspects of dentistry, including enhanced imaging and diagnosis, prevention, bioactive coatings, and targeted treatment of oral diseases. Key highlights encompass the precise control over GNSs' size, crystal structure, shape, and surface functionalization, enabling their integration into sensing, imaging diagnostics, drug delivery systems, and regenerative therapies. GNSs, with their exceptional biocompatibility and antimicrobial properties, have demonstrated efficacy in combating dental caries, periodontitis, peri-implantitis, and oral mucosal diseases. Additionally, they show great promise in the development of advanced sensing techniques for early diagnosis, such as nanobiosensor technology, while their role in targeted drug delivery, photothermal therapy, and immunomodulatory approaches has opened new avenues for oral cancer therapy. Challenges including long-term toxicity, biosafety, immune recognition, and personalized treatment are under rigorous investigation. As research at the intersection of nanotechnology and dentistry continues to thrive, this review highlights the transformative potential of engineered GNSs in revolutionizing dental healthcare, offering accurate, personalized, and minimally invasive solutions to address the oral health challenges of the modern era. [ABSTRACT FROM AUTHOR]

Colloidal metasurfaces are emerging as promising candidates for the development of functional chemical metamaterials, combining the undisputed control over crystallography and surface chemistry achieved by synthetic nanochemistry with the scalability and versatility of colloidal self‐assembly strategies. In light of recent reports of colloidal plasmonic materials displaying high‐performing optical cavities, this Minireview discusses the use of this type of metamaterials in the specific context of non‐linear optical phenomena and non‐linear molecular spectroscopies. Our attention is focused on the opportunities and advantages that colloidal nanoparticles and self‐assembled plasmonic metasurfaces can bring to the table compared to more traditional nanofabrication strategies. Specifically, we believe that future work in this direction will express the full potential of non‐linear molecular spectroscopies to explore the chemical space, with a deeper understanding of plasmon‐molecule dynamics, plasmon‐mediated processes, and surface‐enhanced chemistry. [ABSTRACT FROM AUTHOR]

In this research work, different chemical modifications were applied to gold nanoparticles and their use in enhanced non-classical light emitters based on metal-enhanced fluorescence (MEF) was evaluated. In order to achieve this, gold core–shell nanoparticles with silica shells were modified via multilayered addition and the incorporation of a covalently linked laser dye to develop MEF. Their inter-nanoparticle interactions were evaluated by using additional silica shell multilayers and modified cyclodextrin macrocycles. In this manner, the sizes and chemical surface interactions on the multilayered nanoarchitectures were varied. These optical active nanoplatforms led to the development of different nanoassembly sizes and luminescence behaviors. Therefore, the interactions and nanoassembly properties were evaluated by using various spectroscopic and nanoimaging techniques. Highly dispersible gold core–shell nanoparticles with diameters of 50–60 nm showed improved colloidal dispersion that led to single ultraluminescent gold core–shell nanoparticles with MEF. Then, the addition of variable silica lengths produced increased interactions and consequent nanoaggregation. However, the silanized nanoparticles were easily dispersible after agitation or sonication. Thus, their sizes were proportional only to the diameter and the van de Waals interaction did not affect their sizes in bulk. Then, the covalent linking of different concentrations of modified cyclodextrins was applied to the chemical surfaces by incorporating additional hydroxyl groups from the glucose monomeric unities of cyclodextrins. In this manner, variable larger-sized and inter-branched grafted gold core–shell silica nanoparticles were generated. The ultraluminescent properties were conserved due to the non-optical activity of the cyclodextrins. However, they generated enhanced ultraluminescence phenomena. Laser fluorescence microscopy nanoimaging showed enhanced resolutions in comparison to non-grafted supramolecular gold core–shell nanoparticles. The differences in their interactions and the sizes of the nanoassemblies were explained by their single nanoparticle diameters and the interacting chemical groups on their nanosurfaces. While the varied luminescence emissions generated were tuned by plasmonics, enhanced plasmonic phenomena and light scattering properties were seen depending on the type of nanoassembly. Thus, optically active and non-optically active materials led to different optical properties in the bright field and enhanced the excited state within the electromagnetic near-field of the gold nanotemplates. In this manner, it was possible to achieve high sensitivity by varying the spacer lengths and optical properties. Therefore, further perspectives regarding the design of nano-tools composed of light for various applications were discussed. [ABSTRACT FROM AUTHOR]

In this context, first-time cobalt chromite nanoparticles (CoCr2O4 NPs) were synthesized using honey as a natural precursor through a bio-derived approach. The benefits of this protocol are an easy workup using inexpensive precursors. The textural characteristics of the as-synthesized CoCr2O4 NPs were examined via XRD, FTIR, UV, FESEM, EDX mapping, and VSM studies. Microscopic pictures revealed a cuboidal topology with a mean size of 31.69 nm for greenly produced CoCr2O4 NPs. Furthermore, CoCr2O4 NPs were applied as a heterogeneous catalyst for the facile and one-step formation of 5-aryl-[1,2,4]-triazolidine-3-thiones. The proposed approach offers several admirable benefits, such as straightforwardness, benign reaction systems, shorter reaction time, facile workup, and excellent yield. Also, the as-prepared nanocatalyst was reused (up to 5 cycles) without reducing the significant catalytic performance. Therefore, the present study discloses that synthesizing CoCr2O4 NPs by a facile green approach and assessing robust catalytic performance might benefit nanochemistry research, offering new avenues for organic transformations. [ABSTRACT FROM AUTHOR]

Since 2012, the National Nanoscience Teaching and Training Platform (NNPTTP), funded by the South African Department of Science and Innovation (DSI), has been responsible for overseeing Africa’s first-ever master’s in nanoscience program. For over a decade, the NNPTTP has seen the cooperation of four partner universities across South Africa, namely, the University of Johannesburg (UJ), University of the Free State (UFS), University of the Western Cape (UWC), and Nelson Mandela University (NMU), culminating in over 250 graduates trained in either nanophysics, nanochemistry, or nanobiology. Originally established to train professionals for a nanotechnology-based industry, both in South Africa and internationally, the program and platform has evolved into a testament to scientific collaboration. This paper discusses the program’s framework, successes and challenges, related research, and future plans.

In this research work, different chemical modifications were applied to gold nanoparticles and their use in enhanced non-classical light emitters based on metal-enhanced fluorescence (MEF) was evaluated. In order to achieve this, gold core–shell nanoparticles with silica shells were modified via multilayered addition and the incorporation of a covalently linked laser dye to develop MEF. Their inter-nanoparticle interactions were evaluated by using additional silica shell multilayers and modified cyclodextrin macrocycles. In this manner, the sizes and chemical surface interactions on the multilayered nanoarchitectures were varied. These optical active nanoplatforms led to the development of different nanoassembly sizes and luminescence behaviors. Therefore, the interactions and nanoassembly properties were evaluated by using various spectroscopic and nanoimaging techniques. Highly dispersible gold core–shell nanoparticles with diameters of 50–60 nm showed improved colloidal dispersion that led to single ultraluminescent gold core–shell nanoparticles with MEF. Then, the addition of variable silica lengths produced increased interactions and consequent nanoaggregation. However, the silanized nanoparticles were easily dispersible after agitation or sonication. Thus, their sizes were proportional only to the diameter and the van de Waals interaction did not affect their sizes in bulk. Then, the covalent linking of different concentrations of modified cyclodextrins was applied to the chemical surfaces by incorporating additional hydroxyl groups from the glucose monomeric unities of cyclodextrins. In this manner, variable larger-sized and inter-branched grafted gold core–shell silica nanoparticles were generated. The ultraluminescent properties were conserved due to the non-optical activity of the cyclodextrins. However, they generated enhanced ultraluminescence phenomena. Laser fluorescence microscopy nanoimaging showed enhanced resolutions in comparison to non-grafted supramolecular gold core–shell nanoparticles. The differences in their interactions and the sizes of the nanoassemblies were explained by their single nanoparticle diameters and the interacting chemical groups on their nanosurfaces. While the varied luminescence emissions generated were tuned by plasmonics, enhanced plasmonic phenomena and light scattering properties were seen depending on the type of nanoassembly. Thus, optically active and non-optically active materials led to different optical properties in the bright field and enhanced the excited state within the electromagnetic near-field of the gold nanotemplates. In this manner, it was possible to achieve high sensitivity by varying the spacer lengths and optical properties. Therefore, further perspectives regarding the design of nano-tools composed of light for various applications were discussed.

Polycarboxylate superplasticizers (PCEs) are the most commonly used admixture in the concrete industry. Their premise for work is often considered to be the adsorption of the cement particles through the anchoring groups. Here we suggest a nanoscale perspective to understand the effects of anchoring groups on the adsorption of PCEs by employing the density functional theory (DFT) method. The electronic structural analyses consider various typically anchoring groups of (COO−, PO 4 2−, PO 3 2−, Silanol, and SO 3 −). The findings indicate that anchoring adsorption predominantly occurs at apex calcium and silicon hydroxyl (Si–OH) sites on the C–S–H surface. Specifically, PCEs containing the PO 3 2− groups exhibit the highest degree of chemical adsorption at the apex cacium site, whereas those with COO− groups show the most pronounced chemical adsorption affinity at the Si–OH site. This observation suggests that varying calcium content in cementitious materials may necessitate the use of different anchoring groups for optimal PCE performance. Further analyses of the Reduced Density Gradient (RDG) indicate that PCE with the COO− and PO 3 2− groups demonstrate the most robust adsorption with the corresponding site. Furthermore, quantitative examination of the peak value at the intersection of the electron localization function (ELF) curve derived an inference that aligns with the findings from the RDG analysis. This study provides a robust framework for understanding the adsorption mechanisms of PCEs with various anchoring groups and offers valuable insights for evaluating the performance of PCEs in more complex cementitious systems. [ABSTRACT FROM AUTHOR]

Nanophycology is recognized as one of the most important and widely used interdisciplinary sciences by creating a connection between nanotechnology on the one hand and phycology on the other hand. Algal nanoparticle biosynthesis is a starting point in studies and research related to nanophycology. Nanophycology consists of two parts, nano and phycology, and by taking advantage of the high potential of algae such as high biological safety, easy production, fast growth, and high stability in the phycology part of this science, which is also known as algology, algae nanoparticles synthesis and make this section related to nanotechnology. In this way, algae are known as factories of biological nanomaterials and cause the production of bio-stable nanotechnology and the removal of environmental pollutants released due to nanochemistry. Nanotechnology produced by algae in the science of nanophycology, due to algae's unique physical and chemical properties compared to other biological entities such as plants, fungi, and bacteria, is used in various fields including medicine, biorefining, purification Water, etc. In this review article, the most important goals of the science of nanophycology, including the biosynthesis of algal nanoparticles and the potential of these compounds in various fields of application, have been examined and discussed. [Display omitted] • Nanophycology is the science of integrating nanotechnology in algae-based research. • Biocompatibility of nanotechnology is the most important goal of nanophycology. • Nanophycology provides a suitable solution to control environmental pollutants. • The most important approach of nanophycology is the safe synthesis of nanoparticles based on algae. [ABSTRACT FROM AUTHOR]

High-burnup Zr-based nuclear fuel claddings exhibit accelerated irradiation growth, corrosion and hydrogen pick-up, all correlated with the emergence of c-component dislocation loops. We made use of sub-nm-resolution atom probe tomography to characterize the nanoscale chemistry of c-loops in fuel cladding from boiling water reactor operation. We found segregation of Fe, Ni and Sn to dislocation lines and depletion of Sn and O inside the loops, resulting in nearly pure Zr islands. We also observed nucleation of suboxide inside one c-loop, pointing to a possible mechanism of accelerated in-reactor corrosion. Such Zr-islands might also promote hydride precipitation and associated degradation. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Three Co mineralization stages in the Tuolugou deposit are identified. • Mineral chemistry and nanoscale textural study of the Co pyrite were investigated. • Co mineralization here is related to SEDEX genesis. The Tuolugou sedimentary-exhalative (SEDEX) Co-Au deposit is located in the eastern Kunlun metallogenic belt of the northern Qinghai-Tibet Plateau in China. Pyrite is the prevalent Co-hosting sulfide mineral that occurs in the Tuolugou deposit. In this study, we investigated mineral characteristics of Co-bearing pyrite and effect of Co on crystal structure of the pyrite to obtain a better understanding of Co mineralization. Three pyrite generations were identified, including Co-barren pyrite (Py-1, formed during the early mineralization stage I, with Co content of 1-3844 ppm), Co-rich pyrite (Py-2, formed during the sedimentary-exhalative stage II, Co content 15–36522 ppm), and Co-rich pyrite (Py-3, formed during metamorphic stage III, with Co contents of 448–10505 ppm in Py-3A, and 1371–14904 ppm in Py-3B). As Co enters the pyrite structure, it is discovered that the octahedrons in pyrite is twisted and tilted, the lattice parameters (a 0) rise, and the sulfur atom positions alter. The Co-rich Py-2 shows a similar REE and trace element distribution as those in quartz albitite, which indicates that Co mineralization is related to SEDEX genesis. Subsequent metamorphism resulted in additional Co enrichment. This detailed study of Co-bearing pyrite provides insights on the details of isomorphism Co in pyrite similar to the situation of this deposit as medium–low Co grade. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogen embrittlement (HE) studied in wire arc additive manufactured (WAAM) Al. • Reporting for the first time, WAAM effectively suppresses HE in Al-Zn-Mg-Cu alloys. • Cu content of strengthening precipitates in peak-aged WAAM sample increases. • Many finer precipitates are distributed within grains of peak-aged WAAM sample. • Cu makes strengthening precipitate/matrix interfaces as strong H-trapping sites. In this work, atom probe tomography technique is used to investigate how wire arc additive manufacturing (WAAM) changes the nanochemistry of nanoprecipitates and grain boundaries after peak aging of a high strength Al-Zn-Mg-Cu alloy. The effect of the change in nanochemistry of nanoprecipitates on the hydrogen embrittlement of the additively manufactured aluminum alloy is investigated using a three-point bending test in humid air. The results show that the unique in-process heat treatment during WAAM, offers the possibility to modify the nanochemistry of nanoprecipitates and improve the resistance to hydrogen embrittlement of the Al-Zn-Mg-Cu alloys in the peak aged state without sacrificing mechanical performance. Density functional theory shows that the WAAM process transforms the interfaces between matrix and precipitate into a strong hydrogen trap, which can reduce the hydrogen content of grain boundaries and suppress hydrogen-induced intergranular fracture. [ABSTRACT FROM AUTHOR]

The Guest Editors of Communications Chemistry's Atomically precise nanochemistry Collection discuss the importance of atomic precision in nanochemistry research, and highlight some of the field's most pressing challenges. [ABSTRACT FROM AUTHOR]

Chem Soc Rev Chemical Society Reviewsrsc. li/ chem- soc- rev ISSN 0306- 0012 REVIEW ARTICLE Yangheng Zhang, Wenrong Yang, Fuhua Yan et al . Nanochemistry of gold: from surface engineering to dental healthcare applications Volume 53 Number 8 21 April 2024 Pages 3633– 4304 [Extracted from the article]