A room-temperature refuelable lithium, iodine and air battery.

We demonstrate a new refuelable lithium cell using lithium solvated electron solution (Li-SES) as anolyte and iodine solutions as catholyte. This cell shows a high OCV (~3 V). Unlike conventional rechargeable Li batteries, this kind of cell can be re-fueled in several minutes by replacing the spent liquids. We also show for the first time, that Li-SES/I2 cells which operate at room temperature, can be prepared in a fully discharged state (~0 V OCV) for safe handling, transportation and storage. Li-SES and iodine are then electrochemically generated during charge as is confirmed by UV-VIS and a qualitative test. We have also conducted proof-of-concept tests for an "indirect lithium-air" cell in which iodine is reduced at the cathode and subsequently is catalytically re-oxidized by oxygen dissolved in the catholyte.

1,3,5-Triphenylbenzene and Corannulene as Electron Receptors for Lithium Solvated Electron Solutions.

The authors report on conductivity studies carried out on lithium solvated electron solutions (LiSES) prepared using two types of polyaromatic hydrocarbons (PAH), namely 1,3,5-triphenylbenzene and corannulene, as electron receptors. The solid PAHs were first dissolved in tetrahydrofuran (THF) to form a solution. Metallic lithium was then dissolved into these PAH/THF solutions to yield either blue or greenish blue solutions, colors which are indicative of the presence of solvated electrons. Conductivity measurements at ambient temperature carried out on 1,3,5-triphenylbenzene-based LiSES, denoted by LixTPB(THF)24.7 (x = 1, 2, 3, 4), showed an increase of conductivity with increase of Li:PAH ratio from x = 1 to 2. However, the conductivity gradually decreased upon further increasing the ratio. Indeed the conductivity of LixTPB(THF)24.7 for x = 4 is even lower than for x = 1. Such behavior is similar to that of the previously reported LiSES prepared from biphenyl and naphthalene. Conductivity versus temperature measurements on corannulene-based LiSES, denoted by LixCor(THF)247 (x = 1, 2, 3, 4, 5), showed linear relationships with negative slopes, indicating a metallic behavior similar to biphenyl and naphthalene-based LiSES.

Synthesis and characterization of biphenyl-based lithium solvated electron solutions.

We report on the electric conductivity measurements and FTIR studies carried out on lithium solvated electron solutions (Li-SES) using biphenyl as the electron receptor and tetrahydrofuran (THF) as the solvent. Conductivity measurements carried out on samples with varying compositions of lithium, biphenyl (ß), and THF reveal the highest conductivity of 12.0 mS/cm is achieved with the solution composition Li(1.0)ß(THF)(8.2) and a metallic behavior. Characteristic fingerprint peaks attributed to the solvated electron solution appear in the FTIR spectra. Also, from the FTIR spectra, we propose a reaction mechanism of lithium reaction with biphenyl in THF in that Li(1)ß(THF)(n1) (1 Li atom pairing with 1 biphenyl molecule) is formed first followed by Li(2)ß(THF)(n1) (2 Li atoms pairing with 1 biphenyl molecule). A better understanding of the physical properties of the Li-SES is a prerequisite in view of their optimal applications as liquid anodes in lithium batteries.

Fabrication of Co3O4-reduced graphene oxide scrolls for high-performance supercapacitor electrodes.

A new type of scrolled structure of Co(3)O(4)/reduced graphene oxide (r-GO) is facilely prepared through a two-step surfactant-assisted method. This assembly enables almost every single Co(3)O(4) scroll to connect with the r-GO platelets, thus leading to remarkable electrochemical performances in terms of high specific capacitance and good rate capability.