Direct Probing of Fe 3 O 4 Nanoparticle Surface Temperatures during Magnetic Heating: Implications for Induction Catalysis
Direct Probing of Fe 3 O 4 Nanoparticle Surface Temperatures during Magnetic Heating: Implications for Induction Catalysis
复制标题
磁加热过程中直接探测 Fe 3 O 4 纳米颗粒表面温度：对感应催化的影响
DOI：
10.1021/acsanm.1c03168
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发表时间：
2021
影响因子：
5.9
通讯作者：
Dorman, James A.
中科院分区：
文献类型：
--
作者：
da Silva Moura, Natalia;Bajgiran, Khashayar R.;Melvin, Adam T.;Dooley, Kerry M.;Dorman, James A.
在感应加热过程中，磁性纳米颗粒（NP）表面和体相介质之间存在温度梯度，这在几个领域中已经被观察到。虽然没有观察到本体温度的显著增加，但生物学（DNA变性、肿瘤细胞凋亡）和化学（键断裂）证据表明NP表面附近/处的高温。不幸的是，目前的温度探测方法依赖于大量的温度测量（光纤红外探头）或受到热稳定性和空间分辨率（有机分子）的限制。为了进一步理解磁加热作为催化的驱动力，以及药物输送/热疗治疗，需要更准确地描述纳米颗粒表面温度。这项工作使用与颗粒表面直接接触的无机发光探针，需要在Fe 3 O 4周围沉积YVO 4：Eu 3 +| SiO2结构，用于测量局部温度。发光响应是通过一个受控的温度阶段来提取场依赖性加热的situated校准。发光探头具有高空间分辨率（<5.5 nm），温度比标准光纤探头高64 °C。光致发光（PL）探针与Fe 3 O 4之间的直接接触允许弹道传输和提高时间分辨率，模仿绝热系统（可忽略的远程散热）。其他优点包括避免在液体介质中的测量，其中热源和探针之间的距离不能被控制，由于磁芯的胶体各向异性的变化（其随着加热曲线而变化）和发光信号的表面猝灭而增加了温度测量的不确定性。
The presence of a temperature gradient between the magnetic nanoparticle (NP) surface and the bulk medium during induction heating has been observed across several fields. While no noticeable increase in bulk temperature is observed, biological (DNA denaturation, tumor apoptosis) and chemical (bond cleavage) evidence indicates high temperatures near/at the NP surface. Unfortunately, current methods for temperature probing rely on bulk temperature measurements (fiber-optic IR probes) or are limited by thermal stability and spatial resolution (organic molecules). To further the understanding of magnetic heating as a driving force in catalysis, as well as drug delivery/hyperthermia treatments, a more accurate description of the nanoparticle surface temperature is needed. This work uses inorganic luminescent probes in direct contact with the particle surface, entailing the deposition of YVO4:Eu3+around a Fe3O4|SiO2structure, to measure the local temperature. The luminescent response is calibratedin situvia a controlled temperature stage to extract the field-dependent heating. The luminescent probe results in a high spatial resolution (<5.5 nm) with temperatures up to 64 °C higher than standard fiber-optic probes. The direct contact between the photoluminescence (PL) probe and Fe3O4allows for ballistic transport and improved temporal resolution, mimicking an adiabatic system (negligible long-range heat dissipation). Other advantages include avoiding measurements in liquid media, where the distance between the heat source and the probe cannot be controlled, adding to the uncertainty of the temperature measurement due to changes in colloidal anisotropy (which changes with the heating profile) of the magnetic cores and surface quenching of the luminescent signal.