Operando monitoring of gas bubble evolution in water electrolysis by single high-frequency impedance

Abstract

Gas bubble management is highly demanded in water electrolysis and the lack of real-time monitoring of gas bubbles has slowed down the progress. Here, we demonstrate operando single frequency impedance...

Superaerophobic/Superhydrophilic Multidimensional Electrode System for High-Current-Density Water Electrolysis

“…Although the Ni 3 S 2 surface is typically hydrophobic, the PBSCF-modified Ni 3 S 2 surface was superhydrophilic, as evidenced by its zero CA. The single-frequency EIS analysis further confirmed that the superaerophobic/superhydrophilic characteristics of the PBSCF-Ni 3 S 2 surface significantly reduces the influence of gas bubbles on the electrode interface Figure S13 shows the dynamic variations in resistance responses at fixed frequency of 20 kHz and current density of 100 mA cm –2 for PBSCF-Ni 3 S 2 .…”

“…The single-frequency EIS analysis further confirmed that the superaerophobic/ superhydrophilic characteristics of the PBSCF-Ni 3 S 2 surface significantly reduces the influence of gas bubbles on the electrode interface. 44 According to the solid/liquid/gas interface theory, the arrangement configurations of the nanorods covered by the jagged-shaped perovskite particulates significantly reduce the area of contact between the bubbles and electrode, which minimizes interfacial bubble attachment and promotes the wettability of the electrode. 45,46 Consequently, rapid bubble release from PBSCF-Ni 3 S 2 verifies that the exceptional multidimensional heterostructure array is favorable for enhancing the mass transfer efficiency of the catalyst.…”

In Situ Assembly of a Superaerophobic CoMn/CuNiP Heterostructure as a Trifunctional Electrocatalyst for Ampere-Level Current Density Urea-Assisted Hydrogen Production

“…The fluctuations in resistance can be linked to shifts in the available surface area attributable to the evolving gas bubbles. A higher electrode resistance is associated with prolonged gas bubble existence and larger bubble sizes obstructing the surface . As shown in Figure a, during 240 s, the | Z | value which denotes the specific resistance, for the CoMn/CuNiP/NF electrode functioned with low volatility despite the wild fluctuations in the | Z | value of Pt foil.…”

“…A higher electrode resistance is associated with prolonged gas bubble existence and larger bubble sizes obstructing the surface. 39 As shown in Figure 6a, during 240 s, the |Z| value which denotes the specific resistance, for the CoMn/CuNiP/NF electrode functioned with low volatility despite the wild fluctuations in the |Z| value of Pt foil. Notably, as displayed in Figure 6a, upward and downward peaks correspond to bubbles formed and released, respectively.…”

Bubbles Management for Enhanced Catalytic Water Splitting Performance

“…Additionally, the nanostructured surface of NF exhibits a multi-directional hierarchical structure, which plays a key role in creating gas-repellent surfaces and manipulating bubbles. The effect of surface wetting and anisotropic morphology on gas-bubble evolution (GBE) was monitored by single-frequency impedance [51]. With desirable super-wettability, Ni(OH) 2 @N-NiC/NF heterogeneous layered nanostructured electrodes showed significantly improved alkaline hydrogen evolution reaction (HER) performance (Figure 1b).…”