Ren Hang, German Sean R, Edwards Martin A, Chen Qianjin, White Henry S
Department of Chemistry, University of Utah , Salt Lake City, Utah 84112, United States.
J Phys Chem Lett. 2017 Jun 1;8(11):2450-2454. doi: 10.1021/acs.jpclett.7b00882. Epub 2017 May 19.
Herein, we use Pt nanodisk electrodes (apparent radii from 4 to 80 nm) to investigate the nucleation of individual O nanobubbles generated by electrooxidation of hydrogen peroxide (HO). A single bubble reproducibly nucleates when the dissolved O concentration reaches ∼0.17 M at the Pt electrode surface. This nucleation concentration is ∼130 times higher than the equilibrium saturation concentration of O and is independent of electrode size. Moreover, in acidic HO solutions (1 M HClO), in addition to producing an O nanobubble through HO oxidation at positive potentials, individual H nanobubbles can also be generated at negative potentials. Alternating generation of single O and H bubbles within the same experiment allows direct comparison of the critical concentrations for nucleation of each nanobubble without knowing the precise size/geometry of the electrode or the exact viscosity/temperature of the solution.
在此，我们使用铂纳米盘电极（表观半径为4至80纳米）来研究由过氧化氢（HO）电氧化产生的单个氧纳米气泡的成核过程。当铂电极表面溶解的氧浓度达到约0.17 M时，单个气泡可重复成核。该成核浓度比氧的平衡饱和浓度高约130倍，且与电极尺寸无关。此外，在酸性HO溶液（1 M HClO）中，除了在正电位下通过HO氧化产生一个氧纳米气泡外，在负电位下还可产生单个氢纳米气泡。在同一实验中交替产生单个氧气泡和氢气泡，无需知道电极的确切尺寸/几何形状或溶液的确切粘度/温度，就能直接比较每个纳米气泡成核的临界浓度。
