We describe a technique for preparing highly charged Au nanospheres that can be collected in a quadrupole ion trap and heated beyond the melting point of Au, using a laser, without discharging. Au nanospheres are first added to solutions of ${\left({\mathrm{NH}}_4\right)}_2{\mathrm{CO}}_3$to prepare stable suspensions. Electrospray emission of these suspensions introduces single Au nanospheres into an ion trap in high vacuum, where their charge and mass can be determined from the effect of discrete discharging on their charge to mass ratio, $(q/m)$. After heat treatment to remove residue, $q$ is stable and the nanosphere temperature $T$ can be estimated by mass loss from Au thermal evaporation. Using this technique, we probe the nanosphere melting behavior across the phase transition at $T$=1337 K. Finally, we observe that contaminants in the vacuum, probably C, can have a profound effect on the thermal and optical properties of the Au nanospheres near their melting point.

我们描述了一种制备高度带电的Au纳米球的技术，该技术可收集在四极离子阱中并使用激光加热至Au的熔点以上，而不会放电。首先将金纳米球添加到${（{\mathrm{NH}}_4）}_{\mathrm{2个}}{\mathrm{一氧化碳}}_3$准备稳定的悬架。这些悬浮液的电喷雾发射可在高真空下将单个Au纳米球引入离子阱中，其中的电荷和质量可通过离散放电对其电荷质量比的影响来确定，$（q/米）$。经过热处理去除残留物后，$q$ 稳定且纳米球温度 $Ť$可以通过Au热蒸发的质量损失来估算。使用这项技术，我们在相变处探测了纳米球的熔化行为$Ť$= 1337K。最后，我们观察到真空中的污染物（可能是C）会对金纳米球在其熔点附近的热和光学性质产生深远影响。