Lin D.,University of Alberta |
Zhang X.,University of Alberta |
Cui X.,AdvEn Solutions Inc. |
Chen W.,University of Alberta
RSC Advances | Year: 2014
Highly porous carbons were prepared by using polyaniline (PANI) as a carbon precursor and KOH as an activating agent via a one-step chemical activation process. The effects of the activation parameters such as activation temperature, KOH-PANI weight ratio and pre-heating temperature were fully investigated, through which the pore structure and the materials chemistry of the activated porous carbons were optimized. When studied as an adsorbent for CO2 capture, the optimized porous carbon exhibited a high CO 2 capture capacity of 4.50 mmol g-1, high multi-cycle sorption/desorption stability and highly selective adsorption of CO2 over N2 (0.27 mmol g-1) at 25 °C. This superior performance for CO2 capture was found to be closely related to C-H groups on the carbon surface through hydrogen bonding interactions. © 2014 the Partner Organisations.
Gao M.,University of Alberta |
Cui X.,AdvEn Solutions Inc. |
Wang R.,AdvEn Solutions Inc. |
Wang T.,AdvEn Solutions Inc. |
And 2 more authors.
Journal of Materials Chemistry A | Year: 2015
A unique structure of graphene-wrapped mesoporous single crystals (MSCs) of MnCO3 has been successfully synthesized and used as the anode for lithium-ion batteries (LIBs). In a departure from previous high-temperature (>500 °C) synthesis approaches to MSCs, we have developed a simple, low-temperature (70 °C) and template-free method, referred to as dynamic floating electrodeposition (DFE), to fabricate graphene-wrapped MnCO3 MSCs. In the DFE method, we achieved the reduction of GOs to RGOs, the deposition of MnCO3 MSCs on graphene, and a graphene-wrapped morphology, all three goals in one electrochemical process. The resulting submicron, graphene-wrapped MnCO3 MSCs reached a high reversible capacity of 900 mA h g-1 after the initial cycle and delivered over 1000 mA h g-1 after 130 cycles. The reversible capacity also remained at this high level for more than 400 cycles, and maintained 422 mA h g-1 at a high rate of 5000 mA g-1. It is the first time that this high performance has been achieved using MnCO3 for lithium-ion storage. Furthermore, this superior electrochemical performance was found to be highly related to the designed structure, graphene-wrapped MSCs, of MnCO3. © 2015 The Royal Society of Chemistry.
Adven Solutions Inc. | Date: 2014-01-24
A method of modifying an electrode for an electrochemical cell in which the electrode is in contact with an electrolyte comprising one or more salts containing metal ions and halogen ions connecting the electrode in a circuit comprising the electrode, the electrolyte, and an opposite electrode; and applying a charging current to the circuit charging the circuit to a first voltage sufficient to drive halogen ions into the electrode to modify the atomic structure of the electrode. An electrochemical cell comprising a first electrode, an electrolyte comprising one or more salts containing metal ions and halogen ions; and a second electrode, the second electrode containing halogen ions when the electrochemical cell is in a charged state.
PubMed | AdvEn Solutions Inc., University of Alberta and Canadian National Institute For Nanotechnology
Type: | Journal: Scientific reports | Year: 2014
High performance rechargeable batteries are urgently demanded for future energy storage systems. Here, we adopted a lithium-carbon battery configuration. Instead of using carbon materials as the surface provider for lithium-ion adsorption and desorption, we realized induced fluorination of carbon nanotube array (CNTA) paper cathodes, with the source of fluoride ions from electrolytes, by an in-situ electrochemical induction process. The induced fluorination of CNTA papers activated the reversible fluorination/defluorination reactions and lithium-ion storage/release at the CNTA paper cathodes, resulting in a dual-storage mechanism. The rechargeable battery with this dual-storage mechanism demonstrated a maximum discharging capacity of 2174 mAh (gcarbon)(-1) and a specific energy of 4113 Wh kg(carbon)(-1) with good cycling performance.