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Endohedrally doped clusters form a large category of cage clusters, with unique structures, diverse elemental compositions, and highly tunable electronic structures and physisochemical properties. They have been widely achieved in laboratory and may serve as functional building blocks for assembling new supermolecular structures and devices. In this paper, for the first time, we disclosed the luminescence properties of endohedrally doped group-IV clusters by time-dependent density functional theory calculations. A total of 64 cage clusters have been explored in terms of stability, emission wavelength, and the energy difference between the first excited singlet and triplet states. The key geometric and electronic factors governing the photophysical properties of these cage clusters were unveiled, to provide crucial insights for crafting atomically precise nanoclusters for optical and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Aggregation-induced emission (AIE) is an effective strategy for improving the photoluminescence (PL) performance of metal nanoclusters (MNCs). However, the origin of AIE in MNCs is still not fully understood, which is pivotal for the design of AIE luminogens (AIEgens). Here, water soluble silver nanoclusters (Ag NCs) with AIE properties were synthesized. These as-synthesized non-luminescent Ag NCs will become photoluminescent when transferred from water to ethanol, and the emission peak was redshifted from ∼560 to ∼600 nm and largely intensified with the addition of Cu2+. The addition of Cu2+ makes a big difference in the PL properties of Ag NCs. That is, the PL will be enhanced if Cu2+ is added with the sequence "Ag NCs + Cu2++EtOH." In contrast, the PL will be quenched if Cu2+ is added with the sequence "Ag NCs + EtOH + Cu2+." The PL was from the supramolecular clusters formed by the assembly of capping ligands on the confined surface of individual silver clusters through weak interactions. The addition of Cu2+ could regulate the assembly structure and further affect the energy lever (p-band) through space electron interactions. These results provide new insights into the AIE process in metal nanoclusters. [ABSTRACT FROM AUTHOR]

Clusters are considered to become increasingly significant for elaborating the nanocrystal's formation mechanism. However, capturing the clusters with high chemical potential is challenging because of the lack of effective strategies. In this work, the key role of ligand–solvent interaction has been revealed for the stabilization of clusters in silver telluride synthesis. The Flory interaction coefficient that comprehensively regards the temperature and dispersion, polarity, and hydrogen bonding of the solvent has been used to evaluate the ligand–solvent interaction and thus assist in the design of synthetic systems. Small silver telluride clusters have been successfully captured, and the composition of the smallest cluster is determined as Ag7Te8(SCy)2 (SCy represents the ligand). This work provides new insights into the design of cluster/nanocrystal synthesis systems and paves the way to revealing the mechanism of precursor–cluster–nanocrystal conversion. [ABSTRACT FROM AUTHOR]

A one-step synthesis of porphyrin-silver acetylide clusters from tetra alkyne-substituted porphyrin is described. The solid-state properties of three 2D-like compounds were fully characterised using XPS and XRD while their catalytic properties under CO2 electroreduction reaction conditions were assessed and their faradaic efficiency quantified. [ABSTRACT FROM AUTHOR]

A one-step synthesis of porphyrin-silver acetylide clusters from tetra alkyne-substituted porphyrin is described. The solid-state properties of three 2D-like compounds were fully characterised using XPS and XRD while their catalytic properties under CO2 electroreduction reaction conditions were assessed and their faradaic efficiency quantified. [ABSTRACT FROM AUTHOR]

Diabetic wound healing presents a persistent clinical challenge, often characterized by prolonged healing times, and can be particularly difficult to achieve in a hyperglycemic environment. In this study, a multi‐functional silver‐enzyme nanogels assembly (Ag‐nGHC) is designed by focusing on the complex diabetic wound environment. Glucose oxidase (GOX), horseradish peroxidase (HRP), and catalase (CAT) are modified within polymeric nanogel layers and assembled into a large enzyme cluster with silver ions. The close attachment of three enzymes ensures fast and continuous consumption of a high level of glucose, generation of oxygen, and hydroxyl radicals (•OH) around the wound site. Meanwhile, the silver ions within the Ag‐nGHC assembly act as an effective agent to kill bacteria. This cascade enzyme system significantly improves the microenvironment of the wound site by reducing bacterium infection and alleviating hypoxia as well as hyperglycemia. Sequentially, the improved environment facilitates the later processes including anti‐inflammatory, re‐epithelialization, and angiogenesis, evidenced by enhancing polarization toward M2 macrophages and increasing CD31 signals in this study. Overall, the Ag‐nGHC materials are proven to achieve multifunctional properties toward complicated diabetic wound healing processes (attributes such as adaptability, hypoxia‐alleviated, anti‐hyperglycemic, antimicrobial, anti‐inflammatory, and angiogenic) and showed great potential for the treatment of chronic diabetic wound. [ABSTRACT FROM AUTHOR]

Ultrasmall silver nanoparticles (2 nm) were prepared by reduction with sodium borohydride (NaBH4) and stabilized by the ligand glutathione (a tripeptide: glycine–cysteine–glutamic acid). NMR spectroscopy and optical spectroscopy (UV and fluorescence) revealed that these particles initially consist of silver nanoparticles and fluorescing silver nanoclusters, both stabilized by glutathione. Over time, the silver nanoclusters disappear and only the silver nanoparticles remain. Furthermore, the capping ligand glutathione eliminates hydrogen sulfide (H2S) from the central cysteine and is released from the nanoparticle surface as tripeptide glycine–dehydroalanine–glutamic acid. Hydrogen sulfide reacts with the silver core to form silver sulfide. After four weeks in dispersion at 4 °C, this process is completed. These processes cannot be detected by transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), or differential centrifugal sedimentation (DCS) as these methods cannot resolve the mixture of nanoparticles and nanoclusters or the nature of the nanoparticle core. X-ray photoelectron spectroscopy showed the mostly oxidized state of the silver nanoparticle core, Ag(+I), both in freshly prepared and in aged silver nanoparticles. These results demonstrate that ultrasmall nanoparticles can undergo unnoticed changes that considerably affect their chemical, physical, and biological properties. In particular, freshly prepared ultrasmall silver nanoparticles are much more toxic against cells and bacteria than aged particles because of the presence of the silver clusters. [ABSTRACT FROM AUTHOR]

Designing photoluminescence sensing devices for gaseous oxygen that combine ease of acquisition with efficient performance is a critical yet challenging task. Herein, a novel oxygen‐sensing probe based on zeolite Y confined silver clusters prepared via a simple approach, is proposed. The large Ag6 clusters formed after hydrogenation exhibit a bright orange emission. They are characterized by a high photoluminescence quantum yield (≈31%) and a long luminescence decay time (>500 µs). A possible formation mechanism of these clusters, which are for the first time observed in Faujasite zeolites, is proposed. Luminescence switching‐off, triggered by oxygen, can be detected in a dual‐channel combination of linear emission‐quenching and lifetime‐reduction, enabling a visual and ultrasensitive (limit of detection of 58 Pa) quantitative detection of oxygen in a wide pressure range (0–100 kPa) with fast response (<1 s), reversibility and reproducibility. A more detailed analysis shows that this high sensitivity is due to the long decay time of the orange emission and the high affinity of the zeolite for O2 adsorption rather than to a high rate constant for quenching. This work contributes to the development of optical oxygen sensing technology and lays the foundation for the design of silver cluster‐based zeolites for photo‐functional applications. [ABSTRACT FROM AUTHOR]

A gold(I)‐cluster‐based twin‐cage has been constructed by post‐clustering covalent modification of a hexa‐aldehyde cluster precursor with triaminotriethylamines. The cages‐on‐cluster structure has double cavities and four binding sites, which show site‐discriminative binding for silver(I) and copper(I) guests. The guests in the tripodal hats affect the luminescence of the cluster: the tetra‐silver(I) host–guest complex is weakly red‐emissive, while the bis‐copper(I)‐bis‐silver(I) one is non‐emissive but is a stimuli‐responsive supramolecule. The copper(I) ion inside the tri‐imine cavity is oxidation sensitive, which enables the release of the bright emissive precursor cluster triggered by H2O2 solution. The hybridization of a cluster with cavities to construct a cluster‐based cage presents an innovative concept for functional cluster design, and the post‐clustering covalent modification opens up new avenues for finely tuning the properties of clusters. [ABSTRACT FROM AUTHOR]

Weak doping can broaden, shift, and quench plasmon peaks in nanoparticles, but the mechanistic intricacies of the diverse responses to doping remain unclear. In this study, we used the time-dependent density functional theory (TD-DFT) to compute the excitation properties of transition-metal Pd- or Pt-doped gold and silver atomic arrays and investigate the evolution characteristics and response mechanisms of their plasmon peaks. The results demonstrated that the Pd or Pt doping of the off-centered 10 × 2 atomic arrays broadened or shifted the plasmon peaks to varying degrees. In particular, for Pd-doped 10 × 2 Au atomic arrays, the broadened plasmon peak significantly blueshifted, whereas a slight red shift was observed for Pt-doped arrays. For the 10 × 2 Ag atomic arrays, Pd doping caused almost no shift in the plasmon peak, whereas Pt doping caused a substantial red shift in the broadened plasmon peak. The analysis revealed that the diversity in these doping responses was related to the energy positions of the d electrons in the gold and silver atomic clusters and the positions of the doping atomic orbitals in the energy bands. The introduction of doping atoms altered the symmetry and gap size of the occupied and unoccupied orbitals, so multiple modes of single-particle transitions were involved in the excitation. An electron transfer analysis indicated a close correlation between excitation energy and the electron transfer of doping atoms. Finally, the differences in the symmetrically centered 11 × 2 doped atomic array were discussed using electron transfer analysis to validate the reliability of this analytical method. These findings elucidate the microscopic mechanisms of the evolution of plasmon peaks in doped atomic clusters and provide new insights into the rational control and application of plasmons in low-dimensional nanostructures. [ABSTRACT FROM AUTHOR]

Transparent glass ceramics embedded with YbOF: Er3+ nanocrystals were successfully prepared by melt quenching and cooling methods. The structure and morphology of the YbOF nanocrystals were confirmed by X-ray diffraction, selected area electron diffraction, and transmission electron microscopy. The significant enhancement of upconversion luminescence confirms the doping of Er3+ into the precipitated YbOF nanocrystals. Furthermore, the temperature dependence of the upconversion luminescence was systematically investigated using the fluorescence intensity ratio (FIR) technique under 980 nm excitation. The FIR of the two thermally coupled energy levels of Er3+ ion was validated to be suitable used as temperature probes. The maximum thermal relative sensitivity is about 1.02% K− 1 at 300 K. The results indicate that glass ceramics embedded with YbOF: Er3+ nanocrystals can be used as candidates for temperature sensing. [ABSTRACT FROM AUTHOR]

Ratiometric fluorescence and colorimetric strategies for detecting activity of butyrylcholinesterase (BChE) in human serum were developed by using g-C3N4 nanosheets, silver ion (Ag+) and o-phenylenediamine (OPD) as chromogenic agents. The oxidation-reduction reaction of OPD and Ag+ generates 2,3-diaminophenazine (oxOPD). Under exciation at 370 nm, g-C3N4 nanosheets and oxOPD emit fluorescence at 440 nm (F440) and 560 nm (F560), respectively. Additionally, oxOPD exhibits quenching ability towards g-C3N4 nanosheets via photoinduced electron transfer (PET) process. Thiocholine (TCh), as a product of BChE-catalyzed hydrolysis reaction of butylthiocholine iodide (BTCh), can coordinate with Ag+ intensively, and consequently diminish the amount of free Ag+ in the testing system. Less amount of free Ag+ leads to less production of oxOPD, resulting in less fluorescence quenching towards g-C3N4 nanosheets as well as less fluorescence emission of oxOPD. Therefore, by using g-C3N4 nanosheets and oxOPD as fluorescence indicators, the intensity ratio of their fluorescence (F440/F560) was calculated and employed to evaluate the activity of BChE. Similarly, the color variation of oxOPD indicated by the absorbance at 420 nm (ΔA420) was monitored for the same purpose. These strategies were validated to be sensitive and selective for detecting BChE activity in human serum, with limits of detection (LODs) of 0.1 U L−1 for ratiometric fluorescence mode and 0.7 U L−1 for colorimetric mode. [ABSTRACT FROM AUTHOR]

Dy3+ doped calcium aluminum borosilicate (CABS) glasses have been synthesized via quick melt quench technique. CABS: xDy3+ glasses (x = 0.1, 0.5, 1, 1.5 and 2 mol%) were subjected to various morphological and photoluminescence studies. X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy were conducted to study the structural and bonding nature of the undoped glass. The excitation spectra of Dy3+ doped CABS glasses under 574 nm emission show many sharp peaks amongst which the transition from 6H15/2 → 6P7/2 (351 nm) had the highest intensity. Under 351 nm excitation, glasses exhibit sharp peaks in the blue, yellow and red regions corresponding to the transitions 4F9/2 → 6H15/2, 6H13/2, 6H11/2 and 6H9/2 respectively. The dipole–dipole nature of the interaction between the Dy3+ ions is confirmed via Dexter theory and Inokuti-Hirayama (I-H) model. CIE coordinates estimated from the emission profiles of these glasses under 351 nm excitation fall in the white region. Considering that these glasses exhibit sharp visible emission under UV excitation, have stable yellow to blue (Y/B) ratios and fast decays with intense energy transfers, we propose to utilise these glasses for white light generation and other white light LED (w-LED) and solid-state lighting (SSL) applications. [ABSTRACT FROM AUTHOR]

Glass compositions of 20Li2O-xBi2O3-(78-x)TeO2-1Er2O3-1Ag were fabricated to explore exciton-phonon and exciton-plasmon coupling for laser technology. The Urbach tails analysis indicates increased exciton-phonon coupling at x < 11 mol%, inferred from the disorder parameter Eo. The Elliott-Washington hydrogenic excitonic model highlights a decrease in optical bandgap (Eg) at x < 11 mol% before reaching a maximum at x = 11 mol%. Exciton-phonon coupling was analyzed using the Huang-Rhys parameter S. Fano resonance analysis suggests enhanced exciton-plasmon coupling at x = 5 mol%, leading to enhanced luminescence intensity (2H11/2). Methods including coupling polarizability α(λ), Purcell factor , and Lamb shift were employed to analyze the exciton-plasmon coupling. The ability to fine-tune optical properties is crucial for tailored laser emissions, applicable in light-emitting devices and material processing, where precise laser characteristics are essential. [ABSTRACT FROM AUTHOR]

[Ag6]4+ clusters are extremely rare in nature (only found in Ag-rich tetrahedrite group minerals). Due to their remarkable structures and some promising applications, a few synthesis phases that contain octahedral [Ag6]4+ clusters have been reported. However, the kinds of natural conditions that promote the formation of subvalent hexasilver clusters in tetrahedrite group minerals are still unclear. Kenorozhdestvenskayaite-(Fe), ideally Ag6(Ag4Fe2)Sb4S12□ is a new tetrahedrite group mineral containing a natural [Ag6]4+ cluster, found in the Yindongpo gold deposit, Weishancheng ore field, Henan Province, China. This new species occurs at the edges of galena crystals as anhedral grains of 2 to 20 μm in size and is associated with pyrargyrite, pyrrhotite, and siderite. Kenorozhdestvenskayaite-(Fe) is black in color with metallic luster. It is brittle with conchoidal fracture and has a calculated density of 5.329 g/cm3. The empirical formula calculated on the basis of cation = 16 apfu is M(2)Ag6M(1)(Ag2.41Cu1.20Fe1.84Zn0.71)Σ6.16X(3)(Sb3.82As0.01)Σ3.83S(1)S11.60S(2)□. It is cubic, with space group I 4 3m, a = 10.7119(6) Å, V = 1229.1(2) Å3, and Z = 2. Since kenorozhdestvenskayaite-(Fe) is a new tetrahedrite group mineral containing a natural [Ag6]4+ cluster, its structure is comparable to the synthetic ternary phosphide (Ag6M4P12) M 6 ′ . The presence of the unusual mineral assemblages, i.e., pyrrhotite and pyrargyrite, as well as the other keno-end-member tetrahedrites, indicates a low-fS2 state for the mineralization stage, probably a result of the fluid boiling process in an open system that likely contributed to the formation of S-deficient tetrahedrites. [ABSTRACT FROM AUTHOR]

Metal-mediated base pairs in DNA double helix molecules open up broad opportunities for biosensors based on DNA clusters with silver due to their low toxicity and applicability in drug design. Despite intensive experimental and computational research, molecular mechanisms of stabilization of a double helix by silver-mediated base pairs are mainly unknown. We conducted all-atom molecular dynamics simulations of a dodecameric DNA double helix (sequence 5′-TAGGTCAATACT-3′-3′ATCCACTTATGA-5′) with either cytosine–cytosine or cytosine–Ag+–cytosine mismatch in the center of the duplex. We extended the previously proposed set of interaction parameters for a silver ion in the silver-mediated pair in order to allow for its dissociation. With this new potential, we studied how the addition of a silver ion could stabilize a DNA double helix containing a single cytosine–cytosine mismatch. In particular, we found out that the helix with cytosine–Ag+–cytosine mismatch has a greater melting temperature than the helix with cytosine–cytosine one. This stabilization effect of the silver ion is in qualitative agreement with experimental data. The central region of the duplex with cytosine–Ag+–cytosine mismatch (unlike with cytosine–cytosine mismatch) is stable enough to prevent bubble formation at moderate temperatures during melting. The results of this simulation can be used to devise novel metal-mediated DNA structures. [ABSTRACT FROM AUTHOR]

The self-assembly and gelation processes in low-concentrated aqueous solutions of L-cysteine and silver nitrate (cysteine–silver solution, CSS); low-molecular-weight water-soluble chitosan (CS); and a gelation initiator, CuSO4, have been studied by various physicochemical methods, namely, UV spectroscopy, dynamic light scattering, pH-metry, viscometry, and scanning electron microscopy. It has been found that the gelation of CSS, which is used as a gel precursor, under the action of chitosan (CS) and copper sulfate occurs in a narrow concentration range: CCH = 0.0100–0.0150 mg/mL, = 0.4–0.6 mМ, CL-cys = 3.00 mМ, and = 3.75 mM, when Ag+/Cys molar ratio is 1.27. Hydrogels of various CSS–CS and CSS–CS–CuSO4 compositions possess no high mechanical strength; however, they are stable in the course time. The structural elements of CSS, i.e., cluster chains of silver merchaptide (SM) zwitterions, are positively charged; therefore, no polyelectrolyte complexation occurs in CSS–CS and CSS–CS–CuSO4 hydrogels, because the pH of CSS is 2.6. Addition of CuSO4 to CSS–CS samples promotes the formation of a more strong hydrogel due to the association of SM clusters and CS molecules with sulfate anions and the coordination of Cu(II) ions with deprotonated carboxyl groups of different clusters. [ABSTRACT FROM AUTHOR]

The doping of bismuth (Bi) ions in borosilicate glasses has gained attention for its potential applications in LED light sources and imaging displays. Here, gadolinium oxide (Gd2O3) was introduced into the glass matrix in varying concentrations using a high‐temperature melting method to investigate its impact on the luminescence properties of Bi ions. The resulting glass exhibited bimodal emission peaks at 465 and 750 nm when excited with 325 nm light. The luminescence intensity and fluorescence half width at half height initially increased, followed by a subsequent decrease as the Gd2O3 content in the glass increased from 10 to 43 mol%. Additionally, the color of the luminescence transformed from purple–red to green under white light irradiation. The composition and excitation wavelength of the glass can be adjusted to achieve selective tuning of the luminescence. [ABSTRACT FROM AUTHOR]

The structural, electronic, magnetic, and optical properties of Co-doped 10–20-atom silver clusters are investigated by GGA/PBE via the density functional theory. The Ag–Co clusters form core–shell structures with a Co atom in the center. Co atom doping modulates electronic properties like energy gap, molecular softness, global hardness, electronegativity, and electrophilicity index. For the optical spectra of the Ag–Co clusters, the energy of their spectra overall exhibits little change with increasing numbers of atoms; the strongest peaks are roughly distributed at 3.5 eV, and the intensity of their spectra overall is strengthened. Raman and vibrational spectra reflect structural changes with Co atom addition. The addition of the Co atom alters magnetic moments of specific Ag–Co clusters, while others remain unchanged. [ABSTRACT FROM AUTHOR]

The disadvantage of chalcogenide glasses containing rare earth ions as luminescent materials for the IR optical range is the strong concentration quenching of luminescence due to the non-uniform distribution of rare earth ions in the glass matrix. This study investigates the effect of grinding chalcogenide glass containing Pr3+ ions in a planetary ball mill on its luminescent properties in the near-IR range, as well as its optical properties and structure. The results indicate that milling, under certain conditions, leads to a decrease in the concentration quenching of the luminescence of Pr3+ ions. This finding suggests that milling can be used in the development of glassy materials with the increased efficiency of luminescence of rare earth ions. However, it is essential to consider that high-energy milling may result in the formation of areas with increased pressure in the obtained material, leading to structural changes in the glass. [ABSTRACT FROM AUTHOR]

This study delves into the impact of lithium (Li3+) and silver (Ag7+) ion irradiation on the structure and luminescence of Dy3+ doped and Dy3+/Eu3+ co-doped Gd2MoO6 phosphors, synthesized via the hydrothermal method. To explore the influence of ions with varied mass and energy, 30 MeV Li3+ and 100 MeV Ag7+ ions were employed at different fluences. We elucidate the induced effects based on defect formation and the role of these ions' linear energy transfer (LET) within the irradiated material. SRIM software estimates the depth profile of the ions. Irradiation of the Gd2MoO6 phosphors with Li3+ and Ag7+ ions resulted in the formation of disordered lattices or tracks, modifying their structural, optical, and luminescence properties, which were analyzed by various techniques, including X-ray diffraction, scanning electron microscopy, diffuse reflectance, and photoluminescence. Thermoluminescence (TL) tests and calculations of trapping parameters were conducted to evaluate the dosimetric potential. The findings reveal a more pronounced effect of silver ions compared to lithium ions on the structural and luminescence behavior of doped and codoped Gd2MoO6 phosphors due to their higher atomic weight. [ABSTRACT FROM AUTHOR]

In this work, glass with composition (75- x)B 2 O 3 - x TeO 2 -11Bi 2 O 3 –10Li 2 O-1Ho 2 O 3 -3Yb 2 O 3 (x = 10–60 mol%) were synthesized using the melt quenching technique to investigate the effect of mixed glass former between TeO 2 and B 2 O 3 on the spectroscopic properties of glass. The Raman Spectroscopy has revealed a structural depolymerization undergone by the glasses with a sudden increment at x = 30 mol% that might arise from structural competition between TeO 2 and B 2 O 3. Optical absorption spectra have revealed 9 absorption peaks corresponding to Ho3+ ion transitions while one peak belongs to Yb3+ ion transition. The bonding parameter signifies the glasses are ionic in nature. The oscillator strength and Judd-Ofelt parameter Ω 2 , 4 , 6 have reduced against increment of TeO 2 concentration indicated a low asymmetry and low rigidity except for x = 30 mol% that may be due to strong interaction between TeO 2 and B 2 O 3. The radiative properties such as spontaneous emission probability, branching ratio, radiative lifetime and stimulated emission cross-section have showcased the glass potential for laser application. The luminescence spectra of studied glasses upon 450 nm excitation have disclosed two main emission bands which are 530 nm and 642 nm that corresponding to 5F 4 –5I 8 and 5F 5 –5I 8, of Ho3+ respectively whilst an extra emission recorded at 738 nm was ascribed to 5F 4 –5I 7 of Ho3+ due to energy transfer process from Yb3+ to Ho3+. The emission intensity of the samples has enhanced with the TeO 2 addition due to reduction of phonon energy. CIE 1931 diagram has shown a greener emission colour of glass samples over TeO 2 addition. [ABSTRACT FROM AUTHOR]

The development of stimuli‐responsive circularly polarized luminescence (CPL) materials is quite attractive but challenging. Here, a pair of atomically precise enantiomers R/S‐Ag20 nanoclusters has been synthesized using chiral acid ligands. And then, stimuli‐responsive CPL materials were developed by assembling the chiral silver nanoclusters with an achiral bridging ligand. The atomically precise silver cluster‐assembled materials produce CPL with a dissymmetry factor (|glum|) of 1 × 10−3, through the high‐efficiency chiral induction process. More interestingly, the single CPL band at room temperature could quickly transform into highly separated dual CPL emissions at low temperature. This study provides a new strategy for the rational functionalization of chiral silver clusters in preparing cluster‐based CPL emitters and enriches the types of stimuli‐responsive CPL materials. [ABSTRACT FROM AUTHOR]

Multifunctional cellulosic fibers are in high demand for use in a variety of applications. Functional cellulosic fibers obtained through green and sustainable approaches are getting special attention because of the need to limit the environmental impact of hazardous chemicals. Herein, a novel facile, efficient, and eco-friendly approach for multifunctional viscose fibers@Ag NPs (VF-Ag) was designed by a rapid, facile, and one-pot biosynthesis green route using guava leaf extract as a reducing and stabilizing agent. UV–Vis, TEM, SEM, EDX, FTIR, and XPS were used to analyze the formation of silver nanoparticles and their subsequent deposition on the surface of viscose fibers. The silver nanoparticles immobilized on the surface of viscose fibers endowed a yellow/brownish color to the fibers as well as improving the dyeing with reactive dye. The VF-Ag samples have multifunctional properties like protective activities against UV radiation and microorganisms, antioxidant activity, and sensor ability toward Hg2+. The results demonstrated that the UPF values of VF-Ag samples ranged from 280 to 355 compared to 103 for VF. The antioxidant activities of VF-Ag ranged from 79 to 85% compared to 9% for VF. VF-Ag samples exhibited excellent antimicrobial activities against Gram-positive and Gram-negative bacteria, very good activities against yeast, and low activities against fungus. VF and VF-Ag were dyed using reactive dye (CI-reactive blue-19) at two color intensities (2.5, and 5%). The results show that the color of VF turned blue, while the color of VF-Ag turned greenish. The color strength of VF-Ag significantly increased with increasing silver content. Furthermore, VF-Ag showed high sensitivity to naked-eye colorimetric sensing for the detection of Hg2+. In straightforward, this innovative approach provides an easy, quick, and low-cost that will open the door for a range of versatile applications for modified viscose fibers in the fields of medical and analytical applications. [ABSTRACT FROM AUTHOR]

Polyvinylpyrrolidone (PVP)-protected and strongly luminescent silver nanoclusters (AgNCs@PVP) were synthesized by hydrothermal synthesis under the reduction of formaldehyde aqueous solution. The effects of the concentration ratio of reactants, reaction temperature, reaction time, and pH of the reaction system on the AgNCs@PVP synthesis process were investigated. The luminescent properties, structure, and morphology were characterized. On the basis of the change in AgNCs@PVP fluorescence spectrum caused by hexavalent chromium ion, a method for detecting hexavalent chromium ion was established. Results show a good linear relationship between the concentration of hexavalent chromium ion and the intensity of AgNCs@PVP fluorescence emission spectrum, and the linear range is 2–340 μM. The minimum detection limit is 0.2039 nM, and it was applied to the detection of hexavalent chromium ion in actual water samples. Considering ascorbic acid (AA) can recover the fluorescence quenching of AgNCs@PVP, an "on–off–on" switch was established, and the interaction mechanism of this system was studied in detail. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal Chemical Communications, published by The Royal Society of Chemistry. It includes articles on various topics such as photocatalytic production of hydrogen peroxide, metal-organic frameworks as solid-state electrolytes for lithium batteries, and the redox noninnocence of a phenothiazine-substituted borane. The journal aims to connect the world with the chemical sciences and invest its profits back into the chemistry community. [Extracted from the article]

Two structurally new Lindqvist hexaniobate-templated silver thiolate clusters, [Nb6O19@Ag45(iPrS)23(CH3COO)14] (Ag45) and (H3O)4[Nb6O19@Ag41KS2.5O2(H2O)7.5(iPrS)24(CH3COO)5] (Ag41), were synthesized using a facile one-pot solvothermal approach. Single crystal X-ray diffraction analyses revealed the presence of a classical Lindqvist-type [Nb6O19]8− anion template, with iPrS− and CH3COO− surface-protecting ligands in both silver clusters, which can further form two-dimensional Ag45 assembly and one-dimensional Ag41 chain packing structures. Both Ag45 and Ag41 clusters exhibited intriguing photothermal conversion properties and temperature-dependent emission behavior. [ABSTRACT FROM AUTHOR]

The exploration of individual nanoclusters is rapidly advancing, despite stability concerns. To address this challenge, the assembly of cluster nodes through linker molecules has been successfully implemented. However, the linking of the cluster nodes itself introduces a multitude of possibilities, especially when additional factors come into play. While this method proves effective in enhancing material stability, the specific reasons behind its success remain elusive. In our laboratory, we have undertaken extensive studies on Ag cluster‐assembled materials. So, here our goal is to establish a model system that allows for the discernment of various factors, eliminating unnecessary complexities during the linking approach. So, we hope that the systematic discourse presented in here will contribute significantly to future endeavors, helping to set clear priorities, and provide solutions to concerns that arise when working with a model system. [ABSTRACT FROM AUTHOR]

A series of Dy3+ doped niobiosilicate luminescent glasses have been prepared by high temperature melting using the chemical composition of 35SiO 2 –35Nb 2 O 5 –10Na 2 O–20K 2 O-xDy 2 O 3 (x = 0.2, 0.4, 0.6, 0.8, 1.0 and 1.2 mol%). Results of differential scanning calorimetry (DCS) show that the glass matrix has good thermal stability. Presence of [SiO 4 ] and [NbO 6 ] structural units in the glass was confirmed by FTIR and Raman spectral analyses. Results of UV–Vis–NIR absorption spectra show that Dy3+ doped optical glass can be excited by ultraviolet light, and the transmittance curve displays the high transmittance of the glass. Photoluminescence (PL) analysis reveals that there are three emission peaks: 4F 9/2 → 6H 15/2 (blue light), 4F 9/2 → 6H 13/2 (yellow light), and 4F 9/2 → 6H 11/2 (red light); the highest intensity of the samples is obtained at x = 0.8 mol%, and the variable temperature emission spectrum shows that the emission intensity at 423 K remains above 78.85 % that of room temperature. The CIE chrominance coordinate diagram determines that the chrominance coordinate value is close to the standard white light, the correlation color temperature calculation proves that it is located in the cold white light region. The decay curve can be fitted with the double exponential attenuation equation. The above results show that Dy3+ doped niobiosilicate glass has the potential to be used as W-LED material. [ABSTRACT FROM AUTHOR]

In this work, we have studied, within density functional theory, the interaction of NO with pure and oxidized silver clusters, both anionic and cationic, composed from 11 to 13 Ag atoms. In that size interval, shell closing effects are not expected, and structural and electronic odd–even effects will determine the strength of interaction. First, we obtained that species Ag n ± and AgnO± with odd number of electrons (n = 12) adsorb NO with higher energy than their neighbors (n = 11 and 13). This result is in agreement with the facts observed in recent mass spectroscopy measurements, which were performed, however, at finite temperature. The adsorption energy is about twice for oxidized clusters compared to pure ones and higher for anions than for cations. Second, the adsorption of another NO molecule on AgnNO± forms Ag n (NO) 2 ± , with the dimer (NO)2 in cis configuration, and binding the two N atoms with two neighbor Ag atoms. The n = 12 species show the higher adsorption energy again. Third, in the absence of reaction barriers, all complexes Ag n (NO) 2 ± dissociate spontaneously into AgnO± and N2O, except the n = 12 anion. The maximum high barrier along the dissociation path of Ag 13 (NO) 2 − is about 0.7 eV. Further analysis of projected density of states for Ag 11 − 13 (NO) x ± (x = 0, 1, 2) molecules shows that bonding between NO and Ag clusters mainly occurs in the energy range between −3.0 and 3.0 eV. The overlap between 4d of Ag and 2p of N and O is larger for Ag 12 (NO) 2 ± than for neighbor sizes. For n = 12, the d bands are close to the (NO)2 2π orbital, leading to extra back-donation charge from the 4d of Ag to the closer 2π orbital of (NO)2. [ABSTRACT FROM AUTHOR]

The application of ultraviolet-C light in the field of surface treatment or photodynamic therapy is highly prospective. In this regard, the stable fluorescent silicate SrO-CaO-MgO-SiO2-Pr2O3 glasses able to effectively convert visible excitation on the ultraviolet praseodymium emission were fabricated and examined. An unusual wide-range visible-to-UVC up-conversion within 240–410 nm has been achieved in Pr3+-doped glasses, revealing their potential advantage in different sophisticated disinfection technologies. The integrated emission intensity was studied as a function of light excitation power to assess a mechanism attributed to UVC luminescence. Especially, it was revealed that the multicomponent silicate glass qualities and praseodymium 3PJ excited state peculiarities are favorable to obtaining useful broadband ultraviolet up-converted luminescence. The glass dispersion qualities were determined between 450–2300 nm. The impact of praseodymium concentration on Vis-NIR spectroscopic glass qualities was evaluated employing absorption spectra, emission spectra, and decay curves of luminescence associated with two involved praseodymium excited states. Especially, efficient interionic interactions can be inferred by investigating the decrease in 1D2 state experimental lifetime in the heavily doped samples. Examination of absorption spectra as a function of temperature implied that excitation at 445 nm should be quite effective up to T = 625 K. Contrary to this, temperature elevation gives rise to a moderate lowering of the visible praseodymium luminescence. [ABSTRACT FROM AUTHOR]

Metal-mediated base pairing of DNA has been a topic of extensive research spanning over more than four decades. Precise positioning of a single metal ion by predetermining the DNA sequence, as well as improved conductivity offered by the ions, make these structures interesting candidates in the context of using DNA in nanotechnology. Here, we report the formation and characterization of conjugates of long (kilo bases) homoguanine DNA strands with silver ions. We demonstrate using atomic force microscopy (AFM) and scanning tunneling microscope (STM) that binding of silver ions leads to folding of homoguanine DNA strands in a "hairpin" fashion to yield double-helical, left-handed molecules composed of G-G base pairs each stabilized by a silver ion. Further folding of the DNA–silver conjugate yields linear molecules in which the two halves of the double helix are twisted one against the other in a right-handed fashion. Quantum mechanical calculations on smaller molecular models support the helical twist directions obtained by the high resolution STM analysis. These long guanine-based nanostructures bearing a chain of silver ions have not been synthesized and studied before and are likely to possess conductive properties that will make them attractive candidates for nanoelectronics. [ABSTRACT FROM AUTHOR]

Multi-peak (blue–yellow–red) with warm white light generation of Dy3+ ions-activated zinc leadfluoride-based sodium phosphate (NPZ:60NaPO3 + 25PbF2 + 15ZnF2) glasses were fabricated via the melt and rapid quenching method. The X-ray diffractogram and Raman spectra were studied to examine the amorphous and network structures of NPZDy glasses. The evaluated molar volume and density values increased with the rise in the amount of Dy3+ ions due to the formation of more non-bridging oxygen in the glass network. The result revealed that the Dy3+ ions-doped NPZDy glasses could absorb from 300 to 1800 nm wavelengths and then determined the bandgap energies of NPZDy glasses by using the Tauc's plots. Upon 348 nm of ultraviolet radiation, the fabricated glasses emit red (665 nm), yellow (576 nm), and blue (482 nm) light from the 4F9/2 → 6H11/2,13/2,15/2 transitions of Dy3+ ion. The influence of various molar fraction of Dy3+ ions on the Ω2,4,6 and radiative properties of NPZDy glasses were studied by applying the Judd–Ofelt analysis. The decay times were evaluated by fitting the NPZDy glasses' decays to the bi-exponential function. The larger gain bandwidth of 83.21 × 10–28 cm3 and the maximum quantum efficiency of 79% for NPZDy glasses were calculated by the production of warm white light with (x, y) coordinates of (0.321, 0.361) and relative color temperature of < 4000 K. [ABSTRACT FROM AUTHOR]

Silver-based antibacterial coatings limit the spread of hospital-acquired infections. Indeed, the use of silver and silver oxide nanoparticles (Ag and AgO NPs) incorporated in amorphous hydrogenated carbon (a-C:H) as a matrix demonstrates a promising approach to reduce microbial contamination on environmental surfaces. However, its success as an antibacterial coating hinges on the control of Ag+ release. In this sense, if a continuous release is required, an additional barrier is needed to extend the release time of Ag+. Thus, this research investigated the use of a plasma fluoropolymer (CFx) as an additional top layer to elongate Ag+ release and increase the antibacterial activity due to its high hydrophobic nature. Herein, a porous CFx film was deposited on a-C:H containing Ag and AgO NPs using pulsed afterglow low pressure plasma polymerization. The chemical composition, surface wettability and morphology, release profile, and antibacterial activity were analyzed. Overall, the combination of a-C:H:Ag (12.1 at. % of Ag) and CFx film (120.0°, F/C = 0.8) successfully inactivated 88% of E. coli and delayed biofilm formation after 12 h. Thus, using a hybrid approach composed of Ag NPs and a hydrophobic polymeric layer, it was possible to increase the overall antibacterial activity of the coating. [ABSTRACT FROM AUTHOR]

DNA-stabilized silver nanoclusters with 10 to 30 silver atoms are interesting biocompatible nanomaterials with intriguing fluorescence properties. However, they are not well understood, since atom-scale high level theoretical calculations have not been possible due to a lack of firm experimental structural information. Here, by using density functional theory (DFT), we study the recently atomically resolved (DNA)2–Ag16Cl2 nanocluster in solvent under the lowest-lying singlet (S1) and triplet (T1) excited states, estimate the relative emission maxima for the allowed (S1 → S0) and dark (T1 → S0) transitions, and evaluate the transient absorption spectra. Our results offer a potential interpretation of the recently reported transient absorption and dual emission of similar DNA-stabilized silver nanoclusters, providing a mechanistic view on their photophysical properties that are attractive for applications in biomedical imaging and biophotonics. [ABSTRACT FROM AUTHOR]

Advancing catalyst design requires meticulous control of nanocatalyst selectivity at the atomic level. Here, we synthesized two Pd1Ag14 nanoclusters: Pd1Ag14(PPh3)8(SPh(CF3)2)6 and Pd1Ag14(P(Ph-p-OMe)3)7(SPh)6, each with well-defined structures. Notably, in Pd1Ag14(P(Ph-p-OMe)3)7(SPh)6, the detachment of a phosphine ligand from the top silver atom facilitates the exposure of singular active sites. This exposure significantly enhances its selectivity for the electrocatalytic reduction of CO2 to CO, achieving a Faraday efficiency of 83.3% at −1.3 V, markedly surpassing the 28.1% performance at −1.2 V of Pd1Ag14(PPh3)8(SPh(CF3)2)6. This work underscores the impact of atomic-level structural manipulation on enhancing nanocatalyst performance. [ABSTRACT FROM AUTHOR]

DNA-stabilized silver nanoclusters with 10 to 30 silver atoms are interesting biocompatible nanomaterials with intriguing fluorescence properties. However, they are not well understood, since atom-scale high level theoretical calculations have not been possible due to a lack of firm experimental structural information. Here, by using density functional theory (DFT), we study the recently atomically resolved (DNA)2–Ag16Cl2 nanocluster in solvent under the lowest-lying singlet (S1) and triplet (T1) excited states, estimate the relative emission maxima for the allowed (S1 → S0) and dark (T1 → S0) transitions, and evaluate the transient absorption spectra. Our results offer a potential interpretation of the recently reported transient absorption and dual emission of similar DNA-stabilized silver nanoclusters, providing a mechanistic view on their photophysical properties that are attractive for applications in biomedical imaging and biophotonics. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Binary polyantimony clusters, namely [Cu2Sb14]4– and [Ag2Sb14]4–, containing coinage metals, were successfully synthesized and characterized, in which two homoatomic Sb73– subunits are bridged by two coinage metals in η4:η1 and η1:η1 coordination modes, respectively. In [Cu2Sb14]4–, two bridging Cu ions and two Sb atoms form a planar rhombic unit, which was revealed to have antiaromatic properties by theoretical calculations. Further electron structure and bonding analysis confirmed the presence of delocalized bonds in the rhombic unit and the metallophilic interaction between two formal M+ ions. [ABSTRACT FROM AUTHOR]

Atomically precise metal nanoclusters (NCs) have emerged as a promising frontier in the field of electrochemical CO2 reduction reactions (CO2RR) because of their distinctive catalytic properties. Although numerous metal NCs are developed for CO2RR, their use in practical applications has suffered from their low‐yield synthesis and insufficient catalytic activity. In this study, the large‐scale synthesis and electrocatalytic performance of ClAg14(C≡CtBu)12+ NCs, which exhibit remarkable efficiency in catalyzing CO2‐to‐CO electroreduction with a CO selectivity of over 99% are reported. The underlying mechanisms behind this extraordinary CO2RR activity of ClAg14(C≡CtBu)12+ NCs are investigated by a combination of electrokinetic and theoretical studies. These analyses reveal that different active sites, generated through electrochemical activation, have unique adsorption properties for the reaction intermediates, leading to enhanced CO2RR and suppressed hydrogen production. Furthermore, industrially relevant CO2‐to‐CO electroreduction using ClAg14(C≡CtBu)12+ NCs in a zero‐gap CO2 electrolyzer, achieving high energy efficiency of 51% and catalyst activity of over 1400 A g−1 at a current density of 400 mA cm−2 is demonstrated. [ABSTRACT FROM AUTHOR]

The discrete and charge-separated nature of matter — electrons and nuclei — results in local electrostatic fields that are ubiquitous in nanoscale structures and relevant in catalysis, nanoelectronics and quantum nanoscience. Surface-averaging techniques provide only limited experimental access to these potentials, which are determined by the shape, material, and environment of the nanostructure. Here, we image the potential over adatoms, chains, and clusters of Ag and Au atoms assembled on Ag(111) and quantify their surface dipole moments. By focusing on the total charge density, these data establish a benchmark for theory. Our density functional theory calculations show a very good agreement with experiment and allow a deeper analysis of the dipole formation mechanisms, their dependence on fundamental atomic properties and on the shape of the nanostructures. We formulate an intuitive picture of the basic mechanisms behind dipole formation, allowing better design choices for future nanoscale systems such as single-atom catalysts. Surface averaging techniques offer only limited access to the electrostatic potentials of nanostructures, which are determined by shape, material, and environment. Here, the authors quantify these potentials for gold and silver adatom chains, explaining the mechanisms of dipole formation. [ABSTRACT FROM AUTHOR]

Silver and lanthanide (Tm3+, Yb3+) doped oxyfluoride glasses have been prepared by melt-quenching method. The absorption of the glasses was measured in the range from 350 to 550 nm revealing the absorption edges of Ag nanoclusters and Tm3+ transition. The photoluminescence spectra of the glasses were detected in the range from 400 to 1100 nm under excitation in the range from 300 to 500 nm. The photoluminescence excitation spectra showed that Ag nanoclusters and Tm3+ ions can effectively harvest energy in UV-range and convert to visible and infrared (through emission by Yb3+ ions) ranges making the glasses perspective as white light emitters and solar spectrum downconverters. [ABSTRACT FROM AUTHOR]

Dy3+-embedded glasses have been widely considered for light-emitting diode applications as well as optical display devices. Based on this importance, the present study investigates the structural and photoluminescence characteristics of Dy3+-embedded zincfluoroborophosphate glasses. These glasses with molar composition of 35H3BO3 + 10NH4H2PO4 + 25BaCO3 + (5 − N)La2O3 + 25ZnF2 + NDy2O3 (BPBaLaZfDyN), where N = 2.0, 1.0, 0.5, 0.1, and 0.05, were fabricated by the melt and quenching procedure. FTIR spectra show the existence of fundamental groups such as BO3 and BO4 units, phosphates as well as OH groups. The criterion of metallization, optical electronegativity and basicity of the fabricated glasses was investigated and presented. The three phenomenological Judd–Ofelt (JO) parameters were estimated with the aid of optical absorption of oscillator strengths by using well-known theoretical JO model and in turn estimated the essential radiative characteristics of excited fluorescent states of Dy3+ ion. Dy3+:BPBaLaZfDy glasses reveal the luminescence levels at 840 nm (infrared: 4F9/2 → 6H7/2), 754 nm (infrared: 4F9/2 → 6H9/2), 664 nm (weak red: 4F9/2 → 6H11/2), 485 nm (blue: 4F9/2 → 6H15/2) and 576 nm (yellow: 4F9/2 → 6H13/2), exciting at 350 nm. Among different concentrations, 0.5 mol% (BPBaLaZfDy0.5) glass exhibits relatively more intense emission for 4F9/2 → 6H15/2,13/2,11/2 transitions. From emission data, colour chromaticity coordinates, yellow/blue emission intensity ratio, colour purity and correlated colour temperatures have been determined. The decay times for BPBaLaZfDy glasses were measured with 350 nm excitation and noticed that the radiative de-excitation from 4F9/2 → 6H13/2 state. The fluorescence lifetime values decrease (659 μs to 389 μs) with increase (0.05 to 2.0 mol%) in Dy3+ content. The analysis of the present work confirms the preference of BPBaLaZfDy glasses for the fabrication of optical display components as well as white light luminescence devices. [ABSTRACT FROM AUTHOR]

Thermodynamically metastable glasses that can contain metastable species are important functional materials. X-ray absorption near-edge structure (XANES) spectroscopy is an effective technique for determining the valence states of cations, especially for the doping element in phosphors. Herein, we first confirm the valence change of silver cations from monovalent to trivalent in aluminophosphate glasses by X-ray irradiation using a combination of Ag L3-edge XANES, electron spin resonance, and simulated XANES spectra based on first-principles calculations. The absorption edge of the experimental and simulated XANES spectra demonstrate the spectral features of Ag(III), confirming that AgO exists as Ag(I)Ag(III)O2. A part of Ag(I) changes to Ag(III) by X-ray irradiation, and the generation of Ag(III) is saturated after high irradiation doses, in good agreement with conventional radiophotoluminescence (RPL) behaviour. The structural modelling based on a combination of quantum beam analysis suggests that the local coordination of Ag cations is similar to that of Ag(III), which is confirmed by density functional theory calculations. This demonstration of Ag(III) in glass overturns the conventional understanding of the RPL mechanism of silver cations, redefining the science of silver-related materials. [ABSTRACT FROM AUTHOR]

Silver and copper clusters capped by external chelating dithiolate ligands can be classified according to the cavities in their central coinage metal polyhedra. Silver clusters composed exclusively of fused tetrahedra are analogous to simple saturated organic compounds. The only interstitial atom that can be fit into an Ag4 tetrahedron is hydrogen. Silver polyhedra with larger trigonal prismatic or cubic cavities, including highly distorted cubic cavities, can accommodate halide and chalcogenide anions. The still larger 12-vertex icosahedral and cuboctahedral coinage metal cavities can accommodate oxoanions of the types SO32− and SO42− and their heavier congeners or alternatively interstitial coinage or platinum group metals leading to central M′@M12 units. Copper clusters with central cuboctahedra and silver clusters with central icosahedra possessing interstitial metal atoms approximate sphericality and provide examples of electron-rich metal superatoms with an average metal oxidation state of less than +1. Such copper cluster superatoms have two extra electrons corresponding to a filled 1S2 superatomic orbital. The silver cluster superatoms are electron richer with eight extra electrons corresponding to filled 1S2 + 1P6 superatomic orbitals. In these silver clusters seven or eight faces of the central Ag12 icosahedron are capped by additional silver atoms in order to provide these additional electrons. [ABSTRACT FROM AUTHOR]

The study of facile‐synthesis and low‐cost X‐ray scintillators with high light yield, low detection limit and high X‐ray imaging resolution plays a vital role in medical and industrial imaging fields. However, the optimal balance between X‐ray absorption, decay lifetime and excitonic utilization efficiency of scintillators to achieve high‐resolution imaging is extremely difficult due to the inherent contradiction. Here two thermally activated delayed fluorescence (TADF)‐actived coinage‐metal clusters M6S6L6 (M=Ag or Cu) were synthesized by simple solvothermal reaction, where the cooperation of heavy atom‐rich character and TADF mechanism supports strong X‐ray absorption and rapid luminescent collection of excitons. Excitingly, Ag6S6L6 (SC‐Ag) displays a high photoluminescence quantum yield of 91.6 % and scintillating light yield of 17420 photons MeV−1, as well as a low detection limit of 208.65 nGy s−1 that is 26 times lower than the medical standard (5.5 μGy s−1). More importantly, a high X‐ray imaging resolution of 16 lp/mm based on SC‐Ag screen is demonstrated. Besides, rigid core skeleton reinforced by metallophilicity endows clusters M6S6L6 strong resistance to humidity and radiation. This work provides a new view for the design of efficient scintillators and opens the research door for silver clusters in scintillation application. [ABSTRACT FROM AUTHOR]

The syntheses of atomically precise silver (Ag) clusters stabilized by multidentate lacunary polyoxometalate (POM) ligands have been emerging as a promising but challenging research direction, the combination of redox‐active POM ligands and silver clusters will render them unexpected geometric structures and catalytic properties. Herein, we report the successful construction of two structurally‐new lacunary POM‐stabilized Ag clusters, TBA6H14Ag14(DPPB)4(CH3CN)9[Ag24(Si2W18O66)3] ⋅ 10CH3CN ⋅ 9H2O ({Ag24(Si2W18O66)3}, TBA=tetra‐n‐butylammonium, DPPB=1,4‐Bis(diphenylphosphino)butane) and TBA14H6Ag9Na2(H2O)9[Ag27(Si2W18O66)3] ⋅ 8CH3CN ⋅ 10H2O ({Ag27(Si2W18O66)3}), using a facile one‐pot solvothermal approach. Under otherwise identical synthetic conditions, the molecular structures of two POM‐stabilized Ag clusters could be readily tuned by the addition of different organic ligands. In both compounds, the central trefoil‐propeller‐shaped {Ag24}14+ and {Ag27}17+ clusters bearing 10 delocalized valence electrons are stabilized by three C‐shaped {Si2W18O66} units. The femtosecond/nanosecond transient absorption spectroscopy revealed the rapid charge transfer between {Ag24}14+ core and {Si2W18O66} ligands. Both compounds have been pioneeringly investigated as catalysts for photocatalytic CO2 reduction to HCOOH with a high selectivity. [ABSTRACT FROM AUTHOR]