The influence of relative humidity on charge decay on polystyrene (PS) particles is investigated at room temperature by using Faraday cup and attenuated total reflection‐Fourier transform infrared spectroscopy (ATR‐FTIR) spectroscopy. The PS (2.8 ± 0.4 μm in diameter) particles were charged by using an ozone setup. The ozone charging source was from the free O‐ radicals generated from O₃ dissociation on the surface of the PS particles resulting in carbonyl groups formation. The charge decayed exponentially, and the decay time constants were quantified using Faraday cup for various relative humidity conditions at room temperature. The charge decay due to the interaction of the PS particles with the environment was also investigated using ATR‐FTIR, where the CO stretching band at 1745 cm⁻¹ was monitored. The decay of the CO on the PS particles is due to the reaction of the carbonyl groups with the hydronium ions [H₃O]⁺. The reaction of CO with [H₃O]⁺ is responsible for the time dependent charge decay. From both methods, the charge decay exhibited an exponential behavior, where the time decay constants measured from the two methods were in excellent correlation. The decay time constant increased linearly with increasing the RH. A generalized master charge decay curve is established for any PS surfaces (particles/films).

中文翻译：

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相对湿度对臭氧处理的聚苯乙烯颗粒电荷稳定性的影响

在室温下，通过使用法拉第杯和衰减全反射傅里叶变换红外光谱（ATR-FTIR）光谱研究了相对湿度对聚苯乙烯（PS）颗粒上电荷衰减的影响。通过使用臭氧装置对PS（直径2.8±0.4μm）颗粒进行充电。臭氧带电源来自PS颗粒表面O ₃分解产生的自由基，导致羰基的形成。电荷呈指数衰减，并且使用法拉第杯对室温下各种相对湿度条件下的衰减时间常数进行定量。还使用ATR‐FTIR研究了由于PS粒子与环境的相互作用而导致的电荷衰减，其中CO拉伸带位于1745 cm^-1被监测。PS颗粒上CO的衰减归因于羰基与水合氢离子[H ₃ O] ^+的反应。C = O与[H ₃ O] ⁺的反应是时间依赖性电荷衰减的原因。在这两种方法中，电荷衰减均表现出指数行为，其中两种方法测得的时间衰减常数具有极好的相关性。衰减时间常数随RH的增加而线性增加。为任何PS表面（颗粒/薄膜）建立了通用的主电荷衰减曲线。