Kortschot R J, Bakelaar I A, Erné B H, Kuipers B W M
Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Rev Sci Instrum. 2014 Mar;85(3):033903. doi: 10.1063/1.4867666.
A sensitive dielectric spectroscopy setup is built to measure the response of nanoparticles dispersed in a liquid to an alternating electric field over a frequency range from 10(-2) to 10(7) Hz. The measured complex permittivity spectrum records both the rotational dynamics due to a permanent electric dipole moment and the translational dynamics due to net charges. The setup consists of a half-transparent capacitor connected in a bridge circuit, which is balanced on pure solvent only, using a software-controlled compensating voltage. In this way, the measured signal is dominated by the contributions of the nanoparticles rather than by the solvent. We demonstrate the performance of the setup with measurements on a dispersion of colloidal CdSe quantum dots in the apolar liquid decalin.
搭建了一个灵敏的介电谱装置，用于测量分散在液体中的纳米颗粒在10⁻²至10⁷Hz频率范围内对交变电场的响应。所测量的复介电常数谱记录了由永久电偶极矩引起的旋转动力学以及由净电荷引起的平移动力学。该装置由连接在桥路中的半透明电容器组成，仅使用软件控制的补偿电压在纯溶剂上进行平衡。通过这种方式，所测量的信号主要由纳米颗粒的贡献而非溶剂的贡献主导。我们通过对非极性液体十氢化萘中的胶体CdSe量子点分散体进行测量来展示该装置的性能。
