Designing Breathing Air‐electrode and Enhancing the Oxygen Electrocatalysis by Thermoelectric Effect for Efficient Zn‐air Batteries

Abstract

The sluggish kinetics and mutual interference of oxygen evolution and reduction reactions (OER and ORR) in the air electrode resulted in large charge/discharge overpotential and low energy efficiency of Zn-air batteries. In this work, we designed a breathing air-electrode configuration in Zn-air batteries using P-type Ca3Co4O9 and N-type CaMnO3 as charge and discharge thermoelectrocatalysts, respectively. The Seebeck voltages generated from thermoelectric effect of Ca3Co4O9 and CaMnO3 synergistically compensated the OER and ORR overpotentials. The carrier migration and accumulation on the cold surface of Ca3Co4O9 and CaMnO3 optimized the electronic structure of metallic sites and thus enhanced their intrinsic catalytic activity.The OER and ORR overpotentials were enhanced by 101 and 90 mV, respectively, at temperature gradient of 200 ℃. The breathing Zn-air battery displayed a remarkable energy efficiency of 68.1%. This work provides an efficient avenue towards utilizing waste heat for improving the energy efficiency of Zn-air batteries.

Mn-Doped Zn Metal–Organic Framework-Derived Porous N-Doped Carbon Composite as a High-Performance Nonprecious Electrocatalyst for Oxygen Reduction and Aqueous/Flexible Zinc–Air Batteries

“…First, the increased specific surface area of 30-ZnMn-NC played a crucial role in enhancing the exposure of active sites, resulting in an improved contact between reactants and active sites. , Second, adjacent metals on N-doped carbon substrates typically transfer electrons to the support, which helps to improve the catalyst’s Fermi level and optimize the reaction energy barrier . Lastly, the bimetallic Mn/Zn-N active sites generated by appropriate Mn element doping played a crucial role in synergistically enhancing the ORR activity . These advantages suggest that 30-ZnMn-NC has a promising application in practical energy devices.…”

“…55 Lastly, the bimetallic Mn/Zn-N active sites generated by appropriate Mn element doping played a crucial role in synergistically enhancing the ORR activity. 56 These advantages suggest that 30-ZnMn-NC has a promising application in practical energy devices.…”

Gel Electrolyte with the Sodium Dodecyl Sulfate Additive for Low-Temperature Zinc–Air Batteries

“…Then, the catalyst structure can be maintained, endowing the battery with long-term cycling performance . Among the various transition-metal oxide catalysts, Co 3 O 4 was chosen due to its relatively high OER activity , and outstanding durability in alkaline solutions. , The charge and discharge cycling test presented that the A-PAA gel with 40 wt % KOH provided the maximum cycle time of the battery, and the battery presented a charge voltage of 2.1 V and a discharge voltage of 1.1 V at both room temperature (Figure d) and low temperatures (Figure e) with a current density of 1 mA·cm –1 (Figure S3). Therefore, the 40 wt % KOH aqueous solution was chosen as the immersion solution to prepare the gel electrolyte for low-temperature ZABs.…”

Sustainable Energy Resources for Driving Methane Conversion

“…Interestingly, thermoelectric materials have been also applied to electrocatalysis systems, leading to improved electrocatalytic performance, [ 148 ] and reaction pathways. [ 149 ] Thus, proof of concept research centering on the creative “integration” of thermoelectric materials and electrocatalytic CH 4 conversion technique is of great interest. Another typical one is the waste heat boiler, which can recover the waste heat from the hot exhaust gases and waste streams of exothermic reactions and processes in industrial plants.…”