Harvesting silica nanoparticles from rice husks
Harvesting silica nanoparticles from rice husks
复制标题
从稻壳中收获二氧化硅纳米颗粒
DOI：
10.1007/s11051-011-0609-3
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发表时间：
2011-12-01
影响因子：
2.5
通讯作者：
Sun, Luyi
中科院分区：
文献类型：
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作者：
Wang, Weixing;Martin, Jarett C.;Sun, Luyi
以稻壳为原料，采用控制热解法制备了生物源二氧化硅纳米颗粒。表征结果表明，合成白炭黑的形貌与RHS的预处理和热解条件密切相关。特别是，RHS中的钾离子催化了SiO_2的熔融，在此过程中无定形SiO_2转变为晶相。在700℃下热解2小时似乎是合成直径约20-30 nm的二氧化硅纳米颗粒的理想条件。较高的温度和较长的热解时间会导致二氧化硅纳米颗粒不受欢迎的熔化，而过低的温度不能有效地去除碳基残留物。这种具有窄尺寸分布和高纯度的无定形二氧化硅纳米颗粒有望在各种应用中取代硅胶和气相二氧化硅。
Biogenic silica nanoparticles were synthesized using rice husks (RHs) as the raw material via controlled pyrolysis. The characterization results showed that the morphology of the synthesized silica was highly related to the pretreatment of RHs and the pyrolysis conditions. Particularly, potassium cations in RHs were found to catalyze the melting of silica, during which the amorphous silica were converted to crystalline phase. Two hours of pyrolysis at 700 °C appeared to be ideal to synthesize silica nanoparticles with a diameter of ca. 20–30 nm. Higher temperature and longer duration of pyrolysis led to undesired melting of silica nanoparticles, while too low a temperature cannot effectively remove carbonous residues. Such amorphous silica nanoparticles with narrow size distribution and high purity are expected to replace silica gel and fumed silica for various applications.