Excellent Electrocatalytic Activity of Binuclear Phthalocyanines in the Electrolyte of Lithium/Thionyl Chloride Battery

Abstract

Binuclear nitro-phthalocyanines (M2(PcTN)2O) were synthesized and reduced to binuclear amino-phthalocyanines (M2(PcTA)2O) as high-efficiency catalysts to promote the electrochemical properties of lithium/thionyl chloride (Li/SOCl2) battery. The catalytic performances of M2(PcTN)2O and M2(PcTA)2O were evaluated by adding a small amount of catalysts into the electrolyte. Elemental analysis, Fourier transform infrared (FTIR), ultraviolet-visible (UV-vis), Thermal technique (TGA) and scanning electron microscope (SEM) were employed to characterize the final products. The discharge time of the battery catalyzed by M2(PcTN)2O and M2(PcTA)2O was lengthened by 181∼510 s and 198∼564 s, respectively. The results reveal that battery capacities had been improved approximately 16.74∼47.91% and energy increased by 14.95∼44.80% compared with the bare batteries, which should be attributed to the electronic configurations of the metal ions, the phthalocyanine rings and the synergistic effect. In addition, according to the cyclic voltammetric analysis, catalytic mechanism of the synthesized binuclear phthalocyanines in the battery was speculated.

Transforming a Primary Li-SOCl2 Battery into a High-Power Rechargeable System via Molecular Catalysis

“…Further reduction at the carbon cathode is hindered by the dimerization of the radical, which is the rate-limiting step (a detailed analysis is provided in Supporting Information 1.4). Note that previously reported catalysts, such as metal phthalocyanines, − enhance the discharge performance by improving electron transfer via the delocalized π-electron system and alleviating dimerization via coordination effects between the phthalocyanines and radicals. I 2 fundamentally changes the intermediate, as shown in eqs –, and is thus significantly different from traditional catalysts used in Li-SOCl 2 cells.…”

“…Another bottleneck limiting further application of Li-SOCl 2 batteries is their low-rate discharge performances. In recent decades, molecular catalysts such as transition metal-phthalocyanine complexes ,− have been employed in Li-SOCl 2 systems with the aim of enhancing electron transfer and/or avoiding radical dimerization during discharging. However, the challenge remains as the rate-determining step of discharge is unchanged.…”

Surface Structures, Crystal Orientation, and Electrochemical Behavior of Modified LiFePO4 by Novel Strategies

“…FeSO 4 ·H 2 O (0.0067 mol) was then added into the above solution, controlling the amount of material ratio of Li:P:Fe = 3:1:1. Then, the corresponding additive (0.05 g; Scheme 1, Supporting Information) of the series A, B, C, and D (the amount of mass ratio of CoPcs:CNTs = 2:1 for the additives of B and D series) was added into the solution. Note that all the additives should be ultrasonic for 30 min in 10 mL N,N ‐dimethylformamide before being used to achieve full dispersion.…”

“…Therefore, on the basis of our previous work, here we have chosen mononuclear and binuclear amino cobalt metal phthalocyanines (CoPcTa, Co 2 (PcTa) 2 O) to combine the CNTs in physical integration (CoPcTa/CNTs, Co 2 (PcTa) 2 O/CNTs, B and D of Figure ) to regulate the morphology of the LFP. Moreover, we tried to prepare amino cobalt metal phthalocyanines–bonded CNTs (CoPcTa–CNTs, Co 2 (PcTa) 2 O–CNTs A and C of Figure ) by chemical reactions (Scheme 1, Supporting Information) to obtain novel cathode materials C@LiFe 1− x Co x PO 4 /CNTs, mainly aiming to improve the electrochemical properties of LFP composites.…”

High-Efficiency Electrocatalyst Phthalocyanine in Li/SOCl2 Batteries: From Experimental to Theoretical Investigation

“…Just before this report, 3 we have already found excellent electrocatalytic activity with other phthalocyanines. [4][5][6] Lithium thionyl chloride battery, as one of the most easy-carry energy storage devices rapidly developed in the recent 50 years for its highest capacity among all of the lithium batteries. With the highest open circuit, working voltage, long life, stability voltage, and high specific energy density, it has a wide application prospect.…”