An investigation of commercial carbon air cathode structure in ionic liquid based sodium oxygen batteries

Unravelling the Catalytic Activity of MnO2, TiO2, and VO2 (110) Surfaces by Oxygen Coadsorption on Sodium-Adsorbed MO2 {M = Mn, Ti, V}

Metal-air batteries have attracted extensive research interest owing to their high theoretical energy density. However, most of the previous studies have been limited by applying pure oxygen in the cathode, without taking into consideration the effect of the catalyst, which plays a significant role in the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Adsorption of oxygen on (110) Na-MO₂ is investigated, using density functional theory (DFT) calculations, which is important in the discharging and charging of Na-air batteries. Adsorption of oxygen on Na/MO₂ was investigated, and it was observed that the catalysts encourage the formation of the discharge product reported in the literature, i.e., NaO₂. The surface NaO₂ appears to have bond lengths comparable to those reported for monomer NaO₂.

Research Progress and Perspective on Lithium/Sodium Metal Anodes for Next-Generation Rechargeable Batteries

With the development of consumer electronic devices and electric vehicles, lithium-ion batteries (LIBs) are vital components for high energy storage with great impact on our modern life. However, LIBs still cannot meet all the essential demands of rapidly growing new industries. In pursuance of higher energy requirement, metal batteries (MBs) are the next-generation high-energy-density devices. Li/Na metals are considered as an ideal anode for high-energy batteries due to extremely high theoretical specific capacity (3860 and 1165 mAh g^-1 for Li and Na, respectively) and low electrochemical potential (-3.04 V for Li and -2.71 V for Na vs. standard hydrogen electrode). Unfortunately, uncontrolled dendrite growth, high reactivity, and infinite volume change induce severe safety concerns and poor cycle efficiency during their application. Consequently, MBs are far from commercialization stage. This Review represents a comprehensive overview of failure mechanism of lithium/sodium metal anode and its progress for rechargeable batteries through (i) electrolyte optimization, (ii) artificial solid-electrolyte interphase (SEI) layer formation, and (iii) nanoengineering at materials level in current collector, anode, and host. The challenges in current MBs research and potential applications of lithium/sodium metal anodes are also outlined and summarized.

Investigation on the Potential of Various Biomass Waste for the Synthesis of Carbon Material for Energy Storage Application

The metal–air battery (MAB) has been a promising technology to store energy, with its outstanding energy density, as well as safety features. Yet, the current material used as air cathode is costly and not easily available. This study investigated a few biomass wastes with good potential, including the oil palm empty fruit bunch and garlic peel, as well as the oil palm frond, to determine a sufficiently environmentally-safe, yet efficient, precursor to produce carbon material as an electro-catalyst for MAB. The precursors were carbonized at different temperatures (450, 600, and 700 °C) and time (30, 45, and 60 min) followed by chemical (KOH) activation to synthesize the carbon material. The synthesized materials were subsequently studied through chemical, as well as physical characterization. It was found that PF presented superior tunability that can improve electrical conductivity, due to its ability to produce amorphous carbon particles with a smaller size, consisting of hierarchical porous structure, along with a higher specific surface area of up to 777.62 m2g−1, when carbonized at 600 °C for 60 min. This paper identified that PF has the potential as a sustainable and cost-efficient alternative to carbon nanotube (CNT) as an electro-catalyst for energy storage application, such as MAB.

Efficient heterogeneous catalysis by pendant metalloporphyrin-functionalized polythiophenes for the electrochemical reduction of carbon dioxide

Pendant metalloporphyrin-functionalized polythiophenes serve as efficient catalysts for the practical heterogeneous electrochemical reduction of carbon dioxide under ambient conditions in aqueous media.