Highly efficient electro-generation of H2O2 by adjusting liquid-gas-solid three phase interfaces of porous carbonaceous cathode during oxygen reduction reaction

An, Jingkun; Li, Nan; Zhao, Qian; Qiao, Yujie; Wang, Shu; Liao, Chengmei; Zhou, Lean; Li, Tian; Wang, Xin; Feng, Yujie

doi:10.1016/j.watres.2019.114933

Cited by 129 publications

(70 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is important to emphasize that the PTFE/CB/GDE proposed in this study is fundamentally different from the previous GDE using PTFE as the bulk CB catalyst binder (denoted as PTFE-CB/GDE). 6 , 7 , 36 For the conventional PTFE-CB/GDE, PTFE was blended with CB to provide bulk hydrophobicity. As for the PTFE/CB/GDE cathode, PTFE was only applied on the surface, while the CB layer beneath used the hydrophilic Nafion polymer to promote proton transfer.…”

Section: Resultsmentioning

confidence: 99%

Electrosynthesis of >20 g/L H₂O₂ from Air

Quispe-Cardenas

Yang

et al. 2021

ACS EST Eng.

View full text Add to dashboard Cite

Hydrogen peroxide (HP) production via electrochemical oxygen reduction reaction (ORR-HP) is a critical reaction for energy storage and environmental remediation. The onsite production of high-concentration H 2 O 2 using gas diffusion electrodes (GDEs) fed by air is especially attractive. However, many studies indicate that the air–GDE combination could not produce concentrated H 2 O 2 , as the [H 2 O 2 ] leveled off or even decreased with the increasing reaction time. This study proves that the limiting factors are not the oxygen concentration in the air but the anodic and cathodic depletion of the as-formed H 2 O 2 . We proved that the anodic depletion could be excluded by adopting a divided electrolytic cell. Furthermore, we demonstrated that applying poly(tetrafluoroethylene) (PTFE) as an overcoating rather than a catalyst binder could effectively mitigate the cathodic decomposition pathways. Beyond that, we further developed a composite electrospun PTFE (E-PTFE)/carbon black (CB)/GDE electrode featuring the electrospun PTFE (E-PTFE) nanofibrous overcoating. The E-PTFE coating provides abundant triphase active sites and excludes the cathodic depletion reaction, enabling the production of >20 g/L H 2 O 2 at a current efficiency of 86.6%. Finally, we demonstrated the efficacy of the ORR-HP device in lake water remediation. Cyanobacteria and microcystin-LR were readily removed along with the onsite production of H 2 O 2 .

show abstract

Section: Resultsmentioning

confidence: 99%

Electrosynthesis of >20 g/L H₂O₂ from Air

Quispe-Cardenas

Yang

et al. 2021

ACS EST Eng.

View full text Add to dashboard Cite

show abstract

“…5c-d Table 4, the comparison suggested that the performance of NADE (marked as red star) is, to a large extent, superior to all other airbreathing electrodes (marked as square, see refs. 63,64 ) and normal GDE supplemented by aeration or pressurized oxygen (marked as triangle, see refs. [27][28][29]31,39,[65][66][67][68][69] ).…”

Section: Fabrication and Characterization Of Nade As Presented Inmentioning

confidence: 99%

Highly efficient electrosynthesis of hydrogen peroxide on a superhydrophobic three-phase interface by natural air diffusion

et al. 2020

View full text Add to dashboard Cite

Hydrogen peroxide (H 2 O 2) synthesis by electrochemical oxygen reduction reaction has attracted great attention as a green substitute for anthraquinone process. However, low oxygen utilization efficiency (<1%) and high energy consumption remain obstacles. Herein we propose a superhydrophobic natural air diffusion electrode (NADE) to greatly improve the oxygen diffusion coefficient at the cathode about 5.7 times as compared to the normal gas diffusion electrode (GDE) system. NADE allows the oxygen to be naturally diffused to the reaction interface, eliminating the need to pump oxygen/air to overcome the resistance of the gas diffusion layer, resulting in fast H 2 O 2 production (101.67 mg h-1 cm-2) with a high oxygen utilization efficiency (44.5%-64.9%). Long-term operation stability of NADE and its high current efficiency under high current density indicate great potential to replace normal GDE for H 2 O 2 electrosynthesis and environmental remediation on an industrial scale.

show abstract

“…[ 20 ] A stable three‐phase interface is the basis for active sites to exert their catalytic activity, and has an important impact on the utilization of active sites. [ 21,22 ] However, due to the lack of in‐depth study on the specific transport mechanism of nanopore, how to build a table triple‐phase reaction area, leading to synergistically optimization of ion, electron, and oxygen gas transport at the electrocatalysts, which is essential for high output power and stability of metal–air fuel cells, still remains an open question.…”

Section: Figurementioning

confidence: 99%

Nanopore Confinement of Electrocatalysts Optimizing Triple Transport for an Ultrahigh‐Power‐Density Zinc–Air Fuel Cell with Robust Stability

et al. 2020

View full text Add to dashboard Cite

electrocatalysts to improve their catalytic activity and stability, the realization of a stable and efficient ORR on air electrodes remains a challenge. [4] Generally, advanced metal-air fuel cells require high power output and robust stability. It is vital to build a stable triplephase reaction interface on the electrocatalyst to achieve a perfect balance among electron conduction, oxygen gas diffusion, and ion transportation. [5] However, the masking of active sites in the disorderly stacked electrocatalyst layer in a metalair fuel cell results in sluggish electron transfer. This phenomenon will greatly reduce the efficiency of electron and ion transport, leading to a distinct reduction in the power density. [6] Moreover, the fragile triple-phase interface is easily eroded by water under long-term high current discharging, thereby blocking the oxygen gas transport channel, and causing a significant decline in the stability of the Zn-air fuel cell. [7] To address these issues, the most common strategy is to mix the electrocatalyst and hydrophobic polymer to form a stable three-phase interface and gas transmission channel. In this case, excessive polymer addition greatly increases the reaction resistance and reduces the power density of the Zn-air fuel cell. [8-10] However, fabricating binder-free air electrodes by directly growing electrocatalysts on a conductive substrate can significantly enhance the electrical conductivity. Unfortunately, numerous catalytic sites will be eroded by water flooding in the long-term reaction Metal-air fuel cells with high energy density, eco-friendliness, and low cost bring significantly high security to future power systems. However, the impending challenges of low power density and high-current-density stability limit their widespread applications. In this study, an ultrahigh-power-density Zn-air fuel cell with robust stability is highlighted. Benefiting from the water-resistance effect of the confined nanopores, the highly active cobalt cluster electrocatalysts reside in specific nanopores and possess stable triple-phase reaction areas, leading to the synergistic optimization of electron conduction, oxygen gas diffusion, and ion transport for electrocatalysis. As a result, the as-established Zn-air fuel cell shows the best stability under high-current-density discharging (>90 h at 100 mA cm −2) and superior power density (peak power density: >300 mW cm −2 , specific power: 500 Wg cat −1) compared to most reported non-noble-metal electrocatalysts. The findings will provide new insights in the rational design of electrocatalysts for advanced metal-air fuel cell systems. Metal-air fuel cells are indispensable as next-generation energy storage systems because of their high energy density, eco-friendliness, and low cost. [1] However, the low power density and vulnerable stability of metal-air fuel cells seriously impede their large-scale applications. In particular, a highly efficient and stable power output will be indispensable for emergency backup power supply in future smart po...

show abstract

Highly efficient electro-generation of H2O2 by adjusting liquid-gas-solid three phase interfaces of porous carbonaceous cathode during oxygen reduction reaction

Cited by 129 publications

References 47 publications

Electrosynthesis of >20 g/L H₂O₂ from Air

Electrosynthesis of >20 g/L H₂O₂ from Air

Highly efficient electrosynthesis of hydrogen peroxide on a superhydrophobic three-phase interface by natural air diffusion

Nanopore Confinement of Electrocatalysts Optimizing Triple Transport for an Ultrahigh‐Power‐Density Zinc–Air Fuel Cell with Robust Stability

Contact Info

Product

Resources

About

Highly efficient electro-generation of H2O2 by adjusting liquid-gas-solid three phase interfaces of porous carbonaceous cathode during oxygen reduction reaction

Cited by 129 publications

References 47 publications

Electrosynthesis of >20 g/L H2O2 from Air

Electrosynthesis of >20 g/L H2O2 from Air

Highly efficient electrosynthesis of hydrogen peroxide on a superhydrophobic three-phase interface by natural air diffusion

Nanopore Confinement of Electrocatalysts Optimizing Triple Transport for an Ultrahigh‐Power‐Density Zinc–Air Fuel Cell with Robust Stability

Contact Info

Product

Resources

About

Electrosynthesis of >20 g/L H₂O₂ from Air

Electrosynthesis of >20 g/L H₂O₂ from Air