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The aim of my Ph.D. was to widen the chemistry of heterometallic Rh carbonyl clusters and synthesise and characterize new atomically-precise nanoclusters. Along with this, we evaluated the cytotoxicity of some heterometallic clusters through preliminary biological tests against different cell lines, in order to investigate their possible use in biology. Finally, we started testing homometallic Rh clusters in catalytic processes to compare their performances in low-temperature steam reforming reactions with more conventional Rh-based catalysts. More specifically, over these years we focused our attention on the study of four systems, Rh-Bi, Rh-Ge, Rh-Sb and Rh-Au obtaining several new compounds, which we characterized through single crystal X-ray diffractometry, IR spectroscopy, ESI-MS spectrometry and, in some cases, 31P{1H} NMR. As for the biological part, during my period at the Ecole Polytechnique Fédérale de Lausanne (EPFL), we tested some of our new Rh clusters against three cell lines, namely A2780, A2780cisR and HEK-293, in order to evaluate our species as potential cytotoxic agents. The Rh-Ge clusters achieved the best results. Finally, in collaboration with another research group of our same Department, we tested some Rh clusters as active phases in catalysts for the methane steam reforming at low temperature, obtaining similar results with those achieved by using a conventional Rh-based catalyst.

The total oxidation of toluene was investigated over TiO2-supported gold/iron catalysts prepared utilizing the [NEt4][AuFe4(CO)(16)] bimetallic carbonyl cluster salts. The catalysts have been characterized by means of infra-red spectroscopy (FT-IR), inductively coupled plasma spectrometry (ICP), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), total specific surface area (BET), X-ray photoelectron spectroscopy (XPS) and temperature programmed reduction (TPR) analyses. The novel preparation method resulted in iron oxide species finely and homogeneously distributed on the TiO2 and on small gold nanoparticles. The presence of gold has been found to enhance the selectivity of iron oxides towards the complete oxidation of toluene while the extent of the interaction between the two metals is important for catalytic activity. (C) 2009 Elsevier B.V. All rights reserved.

Il progetto di tesi si è focalizzato sullo studio della reattività del cluster carbonilico [Rh7(CO)16]3- in presenza del sale Au(Et2S)Cl. Ogni reazione investigata è stata svolta in atmosfera controllata di CO, modificando i rapporti stechiometrici tra il precursore e il sale di Au(I) in diversi solventi. Inizialmente si è tentato di riprodurre la sintesi del cluster bimetallico [Rh20Au7(CO)45]5- già noto, utilizzando Au(Et2S)Cl. Si è poi amplificato lo studio con l’obiettivo principale di sintetizzare nuovi cluster bimetallici ad alta nuclearità. È stato ottenuto un composto nuovo analizzato tramite diffrattometria ai raggi X a cristallo singolo: [Rh22Au3(CO)x]n-. Tramite i dati cristallografici è stato possibile definirne la sola struttura metallica, e nonostante i diversi tentativi, il composto non ha prodotto cristalli migliori per una completa caratterizzazione. Viste le quantità significative di sottoprodotti a bassa nuclearità ottenute nelle reazioni studiate, parallelamente sono state condotte prove di recupero del rodio in quanto metallo prezioso. Infine, è stato ottimizzato un metodo per separare due specie già note con carica negativa simile, [Rh10Au(CO)26]3- e [Rh16Au6(CO)36]4-. Tutti i composti sono stati caratterizzati tramite spettroscopia IR, mentre sul nuovo cluster è stata effettuata anche un’analisi alla spettrometria di massa.

Potassium-selenium (K-Se) batteries are an interesting alternative to lithium-selenium (Li-Se) batteries with some notable advantages, such as a reduced cost of production and an environmentally cleaner way of production. Although the idea of K-Se batteries emerged a couple of years ago, in the last few years they have been taken seriously as a capable energy storage. Despite some disadvantages, such as a cathode volume expansion and the shuttle effect, it is considered as an interesting research field and many studies have been carried out. Herein, a carbon host to encapsulate selenium was made to try to reduce the shuttle effect. The defects in the carbon host will be controlled by H2O2 and the products will be analyzed to understand the correlation between the amount of H2O2 and the defects. After encapsulating selenium, the electrochemical proprieties will be analyzed using cyclic voltammetry, galvanostatic charge/discharge. (Additionally, the influence of the concentration of electrolyte will be studied due to the fact that it can modify the electrochemical properties of the batteries). The present project aims to determine if there is a considerable influence on the battery performance owing to the defects of the carbon hosts and the concentration of the electrolyte, and hence to find the best working condition both for K-Se batteries and for the encapsulation.

Within the scope of moving towards a circular economy, “green” materials surely represent an excellent alternative, both in terms of sustainable manufacturing process and circular lifespan. For instance, “bio-composites” are promising bio-based materials constituted by bio-polymers or bio-derived polymers that are reinforced by natural fibres or biological wastes and/or residues. The present Internship and Thesis project took place at Mogu S.r.l., a small Italian company (VA) that creates responsible products for interior design. In details, it focused on the production process of bio-composites tiles for flooring from agro-industrial residues like hemp-shives. The current production protocol was firstly implemented through the investigations of macro-variables: particles’ size and distribution, alternative fibres, different %/dry weight of kraft lignin as binder, temperature and pressure, density and thickness. This allowed to cut by almost 38% the total manufacturing time and reduce the amount of bio-adhesive, thus improving the overall sustainability of the process. Then, alternative bio-adhesives have been tested both in a pure form and after pre-treatments. Precisely, some experimental procedures have been developed to denaturise soy and whey proteins, on the basis of methodologies reported in literature. Finally, the most promising bio-composites were further characterized by performing some mechanical tests. Particularly, the tiles with thermally activated whey proteins isolates as binder showed the best flexural properties, far above the threshold values set by norms. Conversely, further studies will be needed to improve panels’ dimensional stability since also the lowest value of swelling in thickness, recorded for panels with kraft lignin and thermally pre-treated, was not in compliance with norms. Nevertheless, the Project confirmed that it is feasible to reach interesting properties with natural components coming from leftovers of several industries.

Food wastage represents a massive issue in today's society. It impacts the environment (e.g., climate change, resources depletion, biodiversity loss), society (e.g. food security), and the global economy. All the stakeholders could change systemically to transition towards the circular economy. Corporates must involve leadership, employees, suppliers, and consumers to build a more efficient and resilient system where waste and by-products generation is limited. The unavoidable waste could be valorized to new raw materials to reduce the environmental impact of their disposal. This thesis focuses on Barilla (the Italian food company since 1877) and its willingness to valorize by-products (e.g. bread crust), maximizing all aspects of sustainability: economy, ecology, and social equity. First, the author formed an Upcycling Team, an inter-functional group of voluntaries, to define Barilla's criteria for by-products valorization. Afterwards, the Team screened the possible bread crust valorization options (e.g. food product, beer, and animal feed production) using the Analytic Hierarchy Process (AHP), a decision-making tool that allows selecting the best alternative under conflicting criteria. The method's strength is the ability to judge the elements in pairs and use qualitative evaluation. The AHP suggested that producing a food product (e.g. rusk) is the most sustainable option. Furthermore, the author carried out a partial Life Cycle Assessment to compare the global warming potential (GWP) of the production of upcycled rusk to animal feed accounting for the avoided production of the standard products. She demonstrated that producing upcycled rusks using 1 kg of bread crust results in greater net-reduction of GHG emissions than upcycled animal feed. These findings may push Barilla to implement an upcycled food product designed by adopting the eco-design approach to implement a sustainable food product from its raw materials to its end-of-life.

The aim of this project was to synthesize and characterize new high nuclearity heterometallic Rh-Au clusters. The reactivity of rhodium clusters was studied starting from the precursor [Rh7(CO)16]3-, which was oxidated with different Au3+ and Au+ salts. Its behaviour was analysed in different reaction conditions, changing each time the Rh:Au stoichiometric ratio and solvents, under controlled CO atmosphere. Multiple new clusters were obtained: [Rh10Au(CO)26]3-, [Rh16Au6(CO)36]4-, [Rh19Au5(CO)40]4- and [Rh20Au7(CO)45]5-. A clean and reproducible synthetic pathway to synthesize the new [Rh10Au(CO)26]3- was discovered. Moreover, a new synthetic pathway to synthetize [Rh16Au6(CO)36]6- was discovered. Each compound has been characterized via FT-IR spectroscopy and single crystal X-ray diffractometry; [Rh10Au(CO)26]3-, [Rh16Au6(CO)36]4- and [Rh16Au6(CO)36]6- have been also analysed via ESI-MS analysis. Finally, chemical reactivity tests on [Rh10Au(CO)26]3- were conducted, verifying that a consecutive pathway starting from the latter leads to the formation of [Rh16Au6(CO)36]4-.

The aim of the present work is to gain new insights into the formation mechanism of CdTe magic-sized clusters (MSCs) at low temperatures, as well as on their evolution towards 1D and 2D nanostructures and assemblies thereof, under mild reaction conditions. The reaction system included toluene as solvent, octylamine as primary alkylamine, trioctylphosphine-Te as chalcogenide precursor and Cd(oleate)2 as metal precursor. UV-Vis absorption spectroscopy and transmission electron microscopy (TEM) were used to analyze samples containing concentrations of octylamine of 0.2, 0.8 and 2 M: well-defined, sharp absorption peaks were observed, with peaks maxima at 449, 417 and 373 nm respectively, and 1D structures with a string-like appearance were displayed in the TEM images. Investigating peaks growth, step-wise peaks shift to lower energies and reverse, step-wise peak shift to higher energies allowed to propose a model to describe the system, based on interconnected [CdTe]x cluster units originating an amine-capped, 1-dimensional, polymer-like structure, in which different degrees of electronic coupling between the clusters are held responsible for the different absorption transitions. The many parameters involved in the synthesis procedure were then investigated, starting from the Cd:Te ratio, the role of the amine, the use of different phosphine-Te and Cd precursors. The results allowed to gain important information of the reaction mechanism, as well as on the different behavior of the species featuring the sharp absorption peaks in each case. Using Cd(acetate)2 as metal precursor, 2D structures were found to evolve from the MSCs solutions over time, and their tendency to self-assemble was then analyzed employing two amines of different alkyl chain length, octylamine (C-8) and oleylamine (C-18). Their co-presence led to the formation of free-floating triangular nanosheets, which tend to readily aggregate if only octylamine is present in solution.

The topic of my thesis was focused on the synthesis of heteroatomic Rh clusters stabilized by carbonyl ligands. I studied the reactivity of [Rh7(CO)16]3- with different Sb3+ and Ge4+ salts, and tried to synthesize new species by changing the reaction conditions. Indeed, in order to obtain new Rh-Sb and Rh-Ge clusters, I employed different stoichiometric ratios, solvents and atmospheres (N2 or CO). As far as the Rh-Sb system is concerned, I successfully synthesized three new compounds through two different reactions, namely [Rh20Sb3(CO)36][NEt4]3, [Rh21Sb2(CO)38][NEt4]5 and [Rh12Sb(CO)24][NEt4]3. At the same time, I investigated the Rh-Ge system and succeeded in the isolation of the new cluster [Rh14Ge2(CO)30][NEt4]2, along with [Rh12SbGePh2(CO)26][NEt4]2, by treating [Rh7(CO)16]3- with both Ge4+ and Sb3+ salts. Each compound has been characterized by IR spectroscopy, ESI-MS spectrometry and single crystal X-ray diffractometry. Finally, I conduced chemical reactivity tests on some of the obtained compounds.

The quality of human life depends to a large degree on the availability of energy. In recent years, photovoltaic technology has been growing extraordinarily as a suitable source of energy, as a consequence of the increasing concern over the impact of fossil fuels on climate change. Developing affordable and highly efficiently photovoltaic technologies is the ultimate goal in this direction. Dye-sensitized solar cells (DSSCs) offer an efficient and easily implementing technology for future energy supply. Compared to conventional silicon solar cells, they provide comparable power conversion efficiency at low material and manufacturing costs. In addition, DSSCs are able to harvest low-intensity light in diffuse illumination conditions and then represent one of the most promising alternatives to the traditional photovoltaic technology, even more when trying to move towards flexible and transparent portable devices. Among these, considering the increasing demand of modern electronics for small, portable and wearable integrated optoelectronic devices, Fibre Dye-Sensitized Solar Cells (FDSSCs) have gained increasing interest as suitable energy provision systems for the development of the next-generation of smart products, namely “electronic textiles” or “e-textiles”. In this thesis, several key parameters towards the optimization of FDSSCs based on inexpensive and abundant TiO2 as photoanode and a new innovative fully organic sensitizer were studied. In particular, the effect of various FDSSCs components on the device properties pertaining to the cell architecture in terms of photoanode oxide layer thickness, electrolytic system, cell length and electrodes substrates were examined. The photovoltaic performances of the as obtained FDSSCs were fully characterized. Finally, the metal part of the devices (wire substrate) was substituted with substrates suitable for the textile industry as a fundamental step towards commercial exploitation.

The aim of this thesis was to synthesize and to characterize new Rh-In heteroatomic carbonyl clusters. In order to achieve this goal, I investigated the reactivity between [Rh7(CO)16]3- and InCl3. The reactions were carried out with different stoichiometric ratios, testing different solvents and using both a nitrogen atmosphere and a controlled CO atmosphere. Despite the limited selectivity of these reactions, I was able to synthesize and identify five new carbonyl species: [Rh6(CO)15InCl3][NEt4]2, [{Rh6(CO)15InCl2}2][NEt4]2, [{Rh6(CO)15}2In][NEt4], [Rh12In(CO)29][NEt4]3 and [Rh12+xIny(CO)29]3-, although the latter has not been completely identified yet. The former four clusters were characterized by IR spectroscopy, ESI-MS spectrometry and single crystal X-ray diffractometry. Moreover, I performed thermal decomposition and reactivity tests on the [Rh6(CO)15InCl3][NEt4]2 cluster.

Una qualsiasi sostanza che aumenta la fertilità nel terreno e dà il giusto sostentamento alle piante viene detta fertilizzante. Questa classe si può suddividere in tre macro aree: concimi, ammendanti e correttivi. In questo progetto di tesi, svolto presso l’azienda SCAM S.p.A. di Modena, mi sono occupata dello studio e miglioarmento di concimi organo minerali. Si tratta di prodotti intermedi tra i concimi organici, rispetto ai quali hanno un maggior contenuto di elementi nutritivi, e quelli minerali, rispetto ai quali hanno una maggiore efficienza. Lo scopo assegnatomi in questo progetto, è stato quello di ridurre la grandezza del dei grani di concime, uniformare i titoli degli elementi componenti il prodotto, ridurne la friabilità, partendo dallo studio più approfondito di alcune delle materie prime utilizzate per la sua produzione. Il lavoro di ricerca da me svolto ha compreso l’utilizzo di un impianto pilota (tramite il quale sono state condotte le prove), l’analisi dei prodotti ottenuti e l’elaborazione dei dati. Any type of substance that increases soil fertility and gives sustenance to plants is called fertilizer. Fertilizers can be then divided into three macro areas: manures, improvers, and limiting materials. Carried out in SCAM S.p.A., a company based in Modena, this thesis’ project focuses mainly on the study and innovation of organic-mineral manures. These are intermediate materials between organic fertilizers, which in comparison have less nutrients, and minerals, which in comparison are less efficient. The purpose of this project was to reduce the fertilizer grain size, to homogenize the amount of elements in the material and to reduce its brittleness, by starting from an accurate study of some raw materials used for its production. My research included the use of a pilot system (which was used for carrying out tests), the analyses of the obtained materials and of the final data.

Durante il mio progetto di tesi mi sono occupato di cluster carbonilici eterometallici di rodio. Ho investigato la reattività di [Rh7(CO)16]3- con due diversi sali di Au3+, variando i rapporti stechiometrici, provando solventi diversi e sfruttando l’atmosfera controllata di CO per le sintesi, e sia quella inerte di N2 sia quella controllata di H2 per lo studio della reattività. Lo scopo preposto inizialmente era quello di ottimizzare la sintesi di [Rh16Au6(CO)36]6- e, successivamente, tentare di sintetizzare nuovi cluster Rh-Au. Per quanto riguarda la reattività con [AuCl4]- sono riuscito a riprodurre il cluster di interesse e ad ottenerne uno nuovo avente la stessa struttura ma carica differente, [Rh16Au6(CO)36]5-. Parallelamente mi sono occupato della reattività con [AuBr4]-, riuscendo a sintetizzare il cluster [Rh22(CO)37]2-. Successivamente mi sono dedicato allo studio della reattività, ponendo in atmosfere diverse il composto [Rh16Au6(CO)36]6-. Ho ottenuto due nuovi cluster, [Rh18Au(CO)33]3- e [HRh9(CO)20]2-. Tutti i composti sono stati caratterizzati attraverso spettroscopia IR e diffrattometria ai raggi X su cristallo singolo. Su [HRh9(CO)20]2- ho anche effettuato un’analisi 1H-NMR.

Food wastage represents a massive issue in today's society. It impacts the environment (e.g., climate change, resources depletion, biodiversity loss), society (e.g. food security), and the global economy. All the stakeholders could change systemically to transition towards the circular economy. Corporates must involve leadership, employees, suppliers, and consumers to build a more efficient and resilient system where waste and by-products generation is limited. The unavoidable waste could be valorized to new raw materials to reduce the environmental impact of their disposal. This thesis focuses on Barilla (the Italian food company since 1877) and its willingness to valorize by-products (e.g. bread crust), maximizing all aspects of sustainability: economy, ecology, and social equity. First, the author formed an Upcycling Team, an inter-functional group of voluntaries, to define Barilla's criteria for by-products valorization. Afterwards, the Team screened the possible bread crust valorization options (e.g. food product, beer, and animal feed production) using the Analytic Hierarchy Process (AHP), a decision-making tool that allows selecting the best alternative under conflicting criteria. The method's strength is the ability to judge the elements in pairs and use qualitative evaluation. The AHP suggested that producing a food product (e.g. rusk) is the most sustainable option. Furthermore, the author carried out a partial Life Cycle Assessment to compare the global warming potential (GWP) of the production of upcycled rusk to animal feed accounting for the avoided production of the standard products. She demonstrated that producing upcycled rusks using 1 kg of bread crust results in greater net-reduction of GHG emissions than upcycled animal feed. These findings may push Barilla to implement an upcycled food product designed by adopting the eco-design approach to implement a sustainable food product from its raw materials to its end-of-life.

The purpose of my internship, carried out during my Erasmus period at the Complutense University of Madrid, was focused on the formulation of ionogels and hydrogels for the obtainment of films with high lignin content, and on their characterization measuring their antibacterial properties. For biomass formulation I used lignocellulosic biomass (Pinus Radiata) as raw material and ionic liquid as solvent. The two ionic liquids proposed were: 1-ethyl-3-methylimidazoliumdimethylphosphate [Emim][DMP] and 1-ethyl-3-methylimidazoliumdiethylphosphate [Emim][DEP]. The two-starting cellulose-rich solids were obtained from Pinus radiata wood that had been submitted to an organosolv process, to reduce its lignin content to fifteen (ORG15) and twenty per cent (ORG20). Having two ionic liquids and two solids available, the first phase of the project was devoted to the screening of both solids in both ionic liquids. Through this, it was possible to identify that only the [Emim][DMP] ionic liquid fulfils the purpose. It was also possible to discard the cellulose-rich solid ORG20 because its dissolution in the ionic liquid was not possible (after the time fixed) and, additionally, a Pinus radiata cellulose-rich solid bleached with hydrogen peroxide and containing ten per cent of lignin (ORG10B) was included in the screening. After screening, a total of five ionogels were subsequently formulated: two gels were formulated with the starting raw material ORG15 (with 1% and 1.75% cellulose, respectively) and three with ORG10B (with 1%, 1.75% and 3% cellulose, respectively). Five hydrogels were obtained from the ionogels. Rheological tests were performed on each ionogel and hydrogel. Finally, films were formulated from hydrogels and they were analysed by antibacterial testing to see if they could be applied as food packaging. In addition, antioxidant and properties such as opacity and transparency were also studied.

Il progetto di tesi si è focalizzato sullo studio della reattività del cluster carbonilico [Rh7(CO)16]3- in presenza del sale Au(Et2S)Cl. Ogni reazione investigata è stata svolta in atmosfera controllata di CO, modificando i rapporti stechiometrici tra il precursore e il sale di Au(I) in diversi solventi. Inizialmente si è tentato di riprodurre la sintesi del cluster bimetallico [Rh20Au7(CO)45]5- già noto, utilizzando Au(Et2S)Cl. Si è poi amplificato lo studio con l’obiettivo principale di sintetizzare nuovi cluster bimetallici ad alta nuclearità. È stato ottenuto un composto nuovo analizzato tramite diffrattometria ai raggi X a cristallo singolo: [Rh22Au3(CO)x]n-. Tramite i dati cristallografici è stato possibile definirne la sola struttura metallica, e nonostante i diversi tentativi, il composto non ha prodotto cristalli migliori per una completa caratterizzazione. Viste le quantità significative di sottoprodotti a bassa nuclearità ottenute nelle reazioni studiate, parallelamente sono state condotte prove di recupero del rodio in quanto metallo prezioso. Infine, è stato ottimizzato un metodo per separare due specie già note con carica negativa simile, [Rh10Au(CO)26]3- e [Rh16Au6(CO)36]4-. Tutti i composti sono stati caratterizzati tramite spettroscopia IR, mentre sul nuovo cluster è stata effettuata anche un’analisi alla spettrometria di massa.

Within the scope of moving towards a circular economy, “green” materials surely represent an excellent alternative, both in terms of sustainable manufacturing process and circular lifespan. For instance, “bio-composites” are promising bio-based materials constituted by bio-polymers or bio-derived polymers that are reinforced by natural fibres or biological wastes and/or residues. The present Internship and Thesis project took place at Mogu S.r.l., a small Italian company (VA) that creates responsible products for interior design. In details, it focused on the production process of bio-composites tiles for flooring from agro-industrial residues like hemp-shives. The current production protocol was firstly implemented through the investigations of macro-variables: particles’ size and distribution, alternative fibres, different %/dry weight of kraft lignin as binder, temperature and pressure, density and thickness. This allowed to cut by almost 38% the total manufacturing time and reduce the amount of bio-adhesive, thus improving the overall sustainability of the process. Then, alternative bio-adhesives have been tested both in a pure form and after pre-treatments. Precisely, some experimental procedures have been developed to denaturise soy and whey proteins, on the basis of methodologies reported in literature. Finally, the most promising bio-composites were further characterized by performing some mechanical tests. Particularly, the tiles with thermally activated whey proteins isolates as binder showed the best flexural properties, far above the threshold values set by norms. Conversely, further studies will be needed to improve panels’ dimensional stability since also the lowest value of swelling in thickness, recorded for panels with kraft lignin and thermally pre-treated, was not in compliance with norms. Nevertheless, the Project confirmed that it is feasible to reach interesting properties with natural components coming from leftovers of several industries.

Potassium-selenium (K-Se) batteries are an interesting alternative to lithium-selenium (Li-Se) batteries with some notable advantages, such as a reduced cost of production and an environmentally cleaner way of production. Although the idea of K-Se batteries emerged a couple of years ago, in the last few years they have been taken seriously as a capable energy storage. Despite some disadvantages, such as a cathode volume expansion and the shuttle effect, it is considered as an interesting research field and many studies have been carried out. Herein, a carbon host to encapsulate selenium was made to try to reduce the shuttle effect. The defects in the carbon host will be controlled by H2O2 and the products will be analyzed to understand the correlation between the amount of H2O2 and the defects. After encapsulating selenium, the electrochemical proprieties will be analyzed using cyclic voltammetry, galvanostatic charge/discharge. (Additionally, the influence of the concentration of electrolyte will be studied due to the fact that it can modify the electrochemical properties of the batteries). The present project aims to determine if there is a considerable influence on the battery performance owing to the defects of the carbon hosts and the concentration of the electrolyte, and hence to find the best working condition both for K-Se batteries and for the encapsulation.

The aim of this project was to synthesize and characterize new high nuclearity heterometallic Rh-Au clusters. The reactivity of rhodium clusters was studied starting from the precursor [Rh7(CO)16]3-, which was oxidated with different Au3+ and Au+ salts. Its behaviour was analysed in different reaction conditions, changing each time the Rh:Au stoichiometric ratio and solvents, under controlled CO atmosphere. Multiple new clusters were obtained: [Rh10Au(CO)26]3-, [Rh16Au6(CO)36]4-, [Rh19Au5(CO)40]4- and [Rh20Au7(CO)45]5-. A clean and reproducible synthetic pathway to synthesize the new [Rh10Au(CO)26]3- was discovered. Moreover, a new synthetic pathway to synthetize [Rh16Au6(CO)36]6- was discovered. Each compound has been characterized via FT-IR spectroscopy and single crystal X-ray diffractometry; [Rh10Au(CO)26]3-, [Rh16Au6(CO)36]4- and [Rh16Au6(CO)36]6- have been also analysed via ESI-MS analysis. Finally, chemical reactivity tests on [Rh10Au(CO)26]3- were conducted, verifying that a consecutive pathway starting from the latter leads to the formation of [Rh16Au6(CO)36]4-.

The aim of the present work is to gain new insights into the formation mechanism of CdTe magic-sized clusters (MSCs) at low temperatures, as well as on their evolution towards 1D and 2D nanostructures and assemblies thereof, under mild reaction conditions. The reaction system included toluene as solvent, octylamine as primary alkylamine, trioctylphosphine-Te as chalcogenide precursor and Cd(oleate)2 as metal precursor. UV-Vis absorption spectroscopy and transmission electron microscopy (TEM) were used to analyze samples containing concentrations of octylamine of 0.2, 0.8 and 2 M: well-defined, sharp absorption peaks were observed, with peaks maxima at 449, 417 and 373 nm respectively, and 1D structures with a string-like appearance were displayed in the TEM images. Investigating peaks growth, step-wise peaks shift to lower energies and reverse, step-wise peak shift to higher energies allowed to propose a model to describe the system, based on interconnected [CdTe]x cluster units originating an amine-capped, 1-dimensional, polymer-like structure, in which different degrees of electronic coupling between the clusters are held responsible for the different absorption transitions. The many parameters involved in the synthesis procedure were then investigated, starting from the Cd:Te ratio, the role of the amine, the use of different phosphine-Te and Cd precursors. The results allowed to gain important information of the reaction mechanism, as well as on the different behavior of the species featuring the sharp absorption peaks in each case. Using Cd(acetate)2 as metal precursor, 2D structures were found to evolve from the MSCs solutions over time, and their tendency to self-assemble was then analyzed employing two amines of different alkyl chain length, octylamine (C-8) and oleylamine (C-18). Their co-presence led to the formation of free-floating triangular nanosheets, which tend to readily aggregate if only octylamine is present in solution.