It has become a significant problem to develop and improve carbonized polymer dots (CPDs)-based fluorescence sensors with environmental detecting features. In this paper, fluorescent “turn on” sensors of CPDs were...

To overcome the disadvantage that simple bimetallic nanoclusters solutions are difficult to store and utilize, we prepared and obtained a novel gold and copper bimetallic nanoclusters-doped chitosan fluorescent composite film....

No abstract

concentration, environmental conditions, and instrument sensitivity, and they are not easy to measure at any time.In recent years, metal nanoclusters with excellent physical and chemical properties and unique optical properties have been widely studied in optical sensing, environmental science, public safety and medical imaging, etc. [13][14][15][16] Copper nanoclusters (CuNCs) have attracted wide attention due to their excellent fluorescent properties and cheaper than gold and silver. In addition, CuNCs have a special cluster-induced emission enhancement (AIEE) property, that is, when they are in the clusterinduced state, their fluorescent properties are enhanced. [17][18][19][20] Therefore, many fluorescent sensors based on AIEE property of CuNCs have been prepared for detection of metal ions and various solvents, but the single zero-dimensional aqueous nanocluster solution is easy to oxidize, which will reduce the fluorescence intensity as the preparation time is long, and it is not easy to use. [21] The direct solution to this problem is to synthesize metal nanoclusters that meet all the requirements of the expected application. Another strategy is to combine metal nanoclusters with other materials to form nanocomposites containing metal nanoclusters. Therefore, a variety of composite materials based on nanoclusters have been developed one after another. The miniaturization of nanoclusters enables them to be more widely used in practical sensing applications, and the preparation of photoluminescent film devices is a strategy of convenient storage and high utilization. [22][23][24] Alginate (SA) is a typical thermoplastic biopolymer and belongs to an anionic polysaccharide. [25] SA is composed of β-(1,4)-D-mannoturonic ester (M) and α-(1-4)-Gulorolate (G), arranged in the homopolymeric form (Poly-M and Poly-G) and heteropolymeric form (MG or GM). The content of M and G blocks and their relative proportions severely determine the physicochemical properties of SA. SA has been widely used in the preparation of various polymer composites due to its biocompatibility, biodegradability, low cost, non-toxicity, and good film forming property. [26][27][28][29] In addition, there are a large number of free hydroxyl (-OH) and carboxylic acid (COO-) in the main chain of SA, leading to high hydrophilicity of SA. In addition, the pure SA film has rigidity and brittleness and poor mechanical properties. [30] Therefore, SA is mixed with other synthetic materials to improve water sensitivity and mechanical properties.Copper nanoclusters (CuNCs), a new type of fluorescent material, have attracted extensive attention due to their excellent fluorescence properties and stability. In this paper, orange-red organic fluorescent CuNCs are prepared using reduced glutathione both as a template and reducing agent. CuNCs are then doped into a polymer matrix of alginate and polyvinyl alcohol using the aggregation-induced emission enhancement effect to produce a kind of easy to use fluorescent composite films. The fluorescent composite film...