Size-control of species via wavelength to selectively synthesize Ag quantum clusters (QCs) was utilized and the synthesis conditions of this system (AgNO 3 , poly(methacrylic acid) (PMAA) with light) were optimized by changing a variety of parameters. Silver QCs, stabilized by PMAA with different compositions, have been synthesized in aqueous solution by tuning the irradiation monochromatic light wavelengths (300 or 365 nm) and AgNO 3 /MAA ratio (1 or 2). The novel preparation procedure has demonstrated a new approach to enlarge the population of the Ag QC family and proved the effectiveness of size control to prepare Ag QCs by tuning the light wavelength. Naked Ag QC species Ag n (n = 2−9, 11, and 13) in polymer matrices are fully characterized by mass spectrometer, thus providing fingerprinting evidence of their presence. Details regarding the photolysis reaction procedure, Ag QC optical properties, and the origins of fluorescence are discussed. Through a combination of results obtained from mass spectroscopy, fluorescence, and time-dependent density functional theory, we can assign the origin of fluorescence from a small silver cluster of Ag 2 in organic scaffolds. The kinetics of the photolysis reaction follows first-order kinetics (k = 0.1/h). After thiolphenol (C 6 H 5 SH) ligand functionalization of the generated silver clusters in aqueous solution, the low or high resolution mass spectra showed the constant species composites with a molecular formula Ag n L n−1 (n = 2−9 and L = C 6 H 5 S). More evidence indicated the formation of polymer-wrapped silver clusters. Their antibio property was explored, and we confirmed that they indeed show efficient activity.

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Numerous reports of graphene-family nanomaterials (GFNs) promoting plant growth have opened up a wide range of promising potential applications in agroforestry. However, several toxicity studies have raised growing concerns about the biosafety of GFNs. Although these studies have provided clues about the role of GFNs from different perspectives (such as plant physiology, biochemistry, cytology, and molecular biology), the mechanisms by which GFNs affect plant growth remain poorly understood. In particular, a systematic collection of data regarding differentially expressed genes in response to GFN treatment has not been conducted. We summarize here the fate and biological effects of GFNs in plants. We propose that soil environments may be conducive to the positive effects of GFNs but may be detrimental to the absorption of GFNs. Alterations in plant physiology, biochemistry, cytological structure, and gene expression in response to GFN treatment are discussed. Coincidentally, many changes from the morphological to biochemical scales, which are caused by GFNs treatment, such as affecting root growth, disrupting cell membrane structure, and altering antioxidant systems and hormone concentrations, can all be mapped to gene expression level. This review provides a comprehensive understanding of the effects of GFNs on plant growth to promote their safe and efficient use.