Under‐Water Superaerophobic Pine‐Shaped Pt Nanoarray Electrode for Ultrahigh‐Performance Hydrogen Evolution

Abstract

A pine‐shaped Pt nanostructured electrode with under‐water superaerophobicity for ultrahigh and steady hydrogen evolution reaction (HER) performance is successfully fabricated by a facile and easily scalable electrodeposition technique. Due to the lower bubble adhesive force (11.5 ± 1.2 μN), the higher bubble contact angle (161.3° ± 3.4°) in aqueous solution, and the smaller size of bubbles release for pine‐shaped Pt nanostructured electrode, the incomparable under‐water superaerophobicity for final repellence of bubbles from submerged surface with ease, is successfully achieved, compared to that for nanosphere electrode and for Pt flat electrode. With the merits of superior under‐water superaerophobicity and excellent nanoarray morphology, pine‐shaped Pt nanostructured electrode with the ultrahigh electrocatalytic HER performance, excellent durability, no obvious current fluctuation, and dramatically fast current density increase at overpotential range (3.85 mA mV−1, 2.55 and 13.75 times higher than that for nanosphere electrode and for Pt flat electrode, respectively), is obtained, much superior to Pt nanosphere and flat electrodes. The successful introduction of under‐water superaerophobicity to in‐time repel as‐formed H2 bubbles may open up a new pathway for designing more efficient electrocatalysts with potentially practical utilization in the near future.

Superaerophobic graphene nano-hills for direct hydrazine fuel cells

“…The presence (Figure 5a). 9,10,29 This broken TPCL results in a smaller adhesion force of gas bubbles on the surface of the electrode, which eventually leads them to leave the surface quickly (Supplementary Video 2), hence improving the current density of the electrode toward hydrazine oxidation. The broken TPCL arises due to the highly rough nanoscale morphology of the vertically oriented graphene nano-hills.…”

“…This accumulation/adhesion of gas bubbles is the result of a balance between their 'superaerophobic pinning state' and 'superaerophilic bursting state'. 9,10 Both recent reports and our work suggest that designing an ultra-rough, vertical, nanoarchitecture surface will result in a 'superaerophobic' effect that operates via the creation of a discontinuous three-phase (solid-liquid-gas) contact line (TPCL). 11 For example, Lu et al 11 showed that three-dimensional nanoporous electrodeposited copper exhibited a superaerophobic effect and superior electrochemical performance for hydrazine oxidation, owing to its highly rough nanostructured surface.…”

“…9 During the oxidation of hydrazine, the released nitrogen gas gradually accumulates on the surface of the electrode and blocks and reduces its catalytically active accessible surface area available for the hydrazine fuel, which ultimately leads to deteriorated performance of the fuel cell. This accumulation/adhesion of gas bubbles is the result of a balance between their 'superaerophobic pinning state' and 'superaerophilic bursting state'.…”

Recent Progress in Self-Cleaning Materials with Different Suitable Applications

“…TiO 2 films have been improved through the application of Ni 2+ and Fe 3+ to produce self-cleaning active materials in buildings (George et al, 2014;Yong et al, 2014;. Antimicrobial activity of TiO 2 has a huge potential in the construction of building materials for both indoor and outdoor applications Li et al, 2015b;Dunderdale et al, 2015). Antimicrobial activity of TiO 2 is very critical due to their applications in food industries and medical science to preserve food and drug from contamination by microbes.…”

Dialectics of nature in materials science: binary cooperative complementary materials

“…By combining micro/nanostructured substrates and responsive molecules, we can also fabricate smart interfacial materials possessing two complementary properties of superwettability that can be switched using light [22][23][24][25], pH [26][27][28][29][30][31], electric, chemical, or multi-stimuli [32][33][34]. If the design principle is transferred from an air environment to water or other liquid media, underwater superoleophobic and superareophobic surfaces can be developed [35][36][37][38][39][40][41][42]. Furthermore, novel functional solid/liquid interfacial systems, including three-dimensional integrated materials, two-dimensional membranes, one-dimensional fibers/channels, and zero-dimensional nanoparticles, can be generated and integrated into devices by combining different super-wettability properties [43,44].…”