通过柠檬酸钠还原银离子,以银纳米粒子为种子,在室温下制备出平均厚度约为5nm,尺寸40到500nm可调的三角形银纳米片。通过种子调停法可实现银纳米盘的面内偶极表面等离子体共振峰(SPR)从最初的520nm红移至1100nm。通过控制实验参数能够很好地理解其生长机制。柠檬酸根离子和增加到生长液里面的银纳米种子是2个重要的参数,可以控制银纳米盘的大小却不改变银纳米盘的厚度以及晶面结构。采用PVP作为包覆剂,其作用机理还不是很清楚,需要进一步的研究。
Silver nanoplates,with average thickness about 5 nm and average tunable size from 40 to 500 nm,were synthesized via a simple room-temperature solution-phase chemical reduction method in the presence of appropriate concentration of trisodium citrate and silver seeds.The optical in-plane dipole plasmon resonance bands of these silver plates could be tuned from 520 to 1100 nm.Control experiments were explored for understanding of the growth mechanism.It is found that both the amount of citrate ions and the small silver seeds added to the growth solution are the key to controlling the silver nanoplates without changing their thickness and crystal structure.Small silver seeds are found to play an important role in the formation of large thin silver nanoplates when poly(vinylpyrrolidone)(PVP) are used as capping agent.