乙二醇中铜胶体共振光散射光谱

摘要

Copper colloids were synthesized in ethylene glycol by using ascorbic acid ( VC ) as the reducing agent and polyvinyl pyrrolidone( PVP) as the dispersant. The as-prepared copper colloids were characterized by XRD, UV-Vis and resonance light scattering( RLS). Face-centered cubic Cu(0) particles were formed, which displayed resonance light scattering (RLS) spectra with a typical plasma resonance absorption within the range of 592 ~ 602 nm and the maximum scattering wavelength at 468 nm. The RLS results show that the favorable reaction conditions are in the addition order of VC, CuSO4 and PVP under n( VC)/re(Cu2+) = 15, n (PVP-K30)/n( Cu2+ ) =1.4, temperature =60 ℃, and incubating for 1 h. The obtained copper colloids are stable for 24 h. Under such reaction conditions, the scattering intensity(△/RLS) is proportional to Cu2+ content in the range of 5. 12 ~ 12. 8 mg/L with the detection limit of 0. 63 |xg/L(3σ) , and the regression equation is A/ = 7420.2p-631.8 (r =0.9962). When the concentration of Cu2+ solution is 10 mg/L, the colloidal system is stable for 24 h. Foreign substances such as 0. 64 mg/L MnS04, CdSO4 and ZnS04, 1. 28 mg/L of KI, 64 mg/L of NajCO3 and Ca(OH)2, 960 mg/L CH3CH2OH, 640 mg/L CH3OH and 320 mg/L CH3CH2 CH2OH had no interference. Therefore, a simple method to detect the Cu2+ in ethylene glycol is established using the RLS spectra.%在乙二醇中,以聚乙烯吡咯烷酮(PVP)为分散剂,抗坏血酸(VC)为还原剂和抗氧化剂,还原CuSO4制得铜胶体溶液.通过XRD、UV-Vis与共振光散射(RLS)光谱对铜胶体进行表征.结果表明,铜胶体为面心立方晶体结构的0价铜,在592～602 nm呈现典型的等离子共振吸收峰,体系具有明显的RLS特征,最大散射波长在468 nm.考察了反应条件、体系的稳定性与共存离子对乙二醇中铜胶体RLS的影响.结果表明,适宜的反应条件为:试剂按照VC、CuSO4和PVP的加入顺序,3种物质量的比按照n(VC)/n(Cu2+)=15、n( PVP-K30)/n( Cu2+) =1.4;反应温度60℃；反应时间1h,反应得到的铜胶体可稳定放置1d.在适宜条件下,p(Cu2+)在5.12～12.8 mg/L范围内与散射光强度(ΔIRLS)成正比,同归方程为ΔI=7420.2ρ - 631.8(r=0.9962),检出限(3σ)为0.63 μg/L.0.64 mg/L MnSO4、CdSO4和ZnSO4,1.28 mg/L KI,64 mg/L Na2 CO3和Ca(OH)2,960 mg/L CH3CH2OH,640 mg/L CH3OH和320 mg/L CH3CH2CH2OH均不干扰10 mg/L Cu2+溶液的测量.由此建立一种利用RLS光谱测定乙二醇中铜离子的简便方法.