The Effect of Gadolinium Ion Doping on Electronic Conductivity of LiFePO4/C

In the recent years, LiFePO4 has been widely developed as a cathode for lithium ion batteries because it has high theoretical capacity (170 mAh/g), good stability and is also environmentally friendly. However, the poor electronic conductivity (~10-9 S/cm) and low diffusion coefficient of lithium ion (~10-15-10-14 cm2/s) are limiting its application. Some solutions to overcome this problem are carbon coating and doping metal ions. This study aims to determine the effect of Gd3+ ion doping on the electronic conductivity of LiFePO4/C. The synthesis method was used is carbothermal reduction with Fe2O3, Gd2O3, LiH2PO4 and carbon black reagents. The synthesized LiFe1-xGdxPO4/C was characterized using XRD, SEM-EDS, and four point probes. The results obtained showed that gadolinium ion doping increased the conductivity of LiFePO4/C from 1.8952 x10-6 to 8.69x10-6 Scm-1 using 0.07 mol ion Gd3+.

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Li3VO4 micro/nanoscale anode with fast ion transportation for advanced lithium-ion batteries: a mini-review

Journal of Materials Chemistry C ◽

10.1039/d1tc03757a ◽

2021 ◽

Author(s):

Miaomiao Wang ◽

Chunsheng Li ◽

Yan Sun ◽

Yang Chen ◽

Lin Li ◽

...

Keyword(s):

Crystal Structure ◽

Lithium Ion Batteries ◽

Electronic Conductivity ◽

Lithium Ion ◽

The Poor ◽

High Theoretical Capacity ◽

Ion Transportation ◽

Fast Ion

In recent years, Li3VO4 has been considered as a promising anode for advanced lithium-ion batteries due to its special crystal structure and high theoretical capacity. However, the poor electronic conductivity...

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PEDOT-Coated Red Phosphorus Nanosphere Anodes for Pseudocapacitive Potassium-Ion Storage

Nanomaterials ◽

10.3390/nano11071732 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1732

Author(s):

Dan Zhao ◽

Qian Zhao ◽

Zhenyu Wang ◽

Lan Feng ◽

Jinying Zhang ◽

...

Keyword(s):

Surface Engineering ◽

Electronic Conductivity ◽

Specific Capacity ◽

Lithium Ion ◽

Average Diameter ◽

Potassium Ion ◽

Red Phosphorus ◽

Fast Charging ◽

Potential Alternative ◽

High Theoretical Capacity

Potassium-ion batteries (KIBs) have come up as a potential alternative to lithium-ion batteries due to abundant potassium storage in the crust. Red phosphorus is a promising anode material for KIBs with abundant resources and high theoretical capacity. Nevertheless, large volume expansion, low electronic conductivity, and limited K+ charging speed in red phosphorus upon cycling have severely hindered the development of red phosphorus-based anodes. To obtain improved conductivity and structural stability, surface engineering of red phosphorus is required. Poly(3,4-ethylenedioxythiophene) (PEDOT)-coated red phosphorus nanospheres (RPNP@PEDOT) with an average diameter of 60 nm were synthesized via a facile solution-phase approach. PEDOT can relieve the volume change of red phosphorus and promote electron/ion transportation during charge−discharge cycles, which is partially corroborated by our DFT calculations. A specific capacity of 402 mAh g−1 at 0.1 A g−1 after 40 cycles, and a specific capacity of 302 mAh g−1 at 0.5 A g−1 after 275 cycles, were achieved by RPNP@PEDOT anode with a high pseudocapacitive contribution of 62%. The surface–interface engineering for the organic–inorganic composite of RPNP@PEDOT provides a novel perspective for broad applications of red phosphorus-based KIBs in fast charging occasions.

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Effect of MgO Coating on the Hydration Resistance of MgO-CaO Clinkers

Materials Science Forum ◽

10.4028/www.scientific.net/msf.695.324 ◽

2011 ◽

Vol 695 ◽

pp. 324-327 ◽

Cited By ~ 12

Author(s):

Hong Feng Yin ◽

Yan Long Ma ◽

Jun Yang

Keyword(s):

Carbon Source ◽

Carbon Black ◽

Reaction Temperature ◽

Carbothermal Reduction ◽

Processing Parameters ◽

Holding Time ◽

Deposition Mechanism ◽

The Poor ◽

Hydration Resistance ◽

Prolonged Holding

To overcome the disadvantage of MgO-CaO refractories, as the poor hydration resistance, MgO coating on the MgO-CaO clinker was fabricated by carbothermal reduction MgO with carbon as reduction agent and then the oxidation of Mg vapor. Effect of processing parameters (such as carbon source, reaction temperature and holding time) on the hydration resistance of MgO-CaO clinkers were investigated by hydration resistance test and SEM. The results indicated that the hydration resistance of treated MgO-CaO clinkers was improved when carbon black was used as reduction agent due to easy reaction with MgO than the graphite and coke. The high reaction temperature among 1450~1600°C and prolonged holding time within 4 h resulted in improvement of the hydration resistance of treated MgO-CaO clinker. Deposition mechanism of MgO coating on the MgO-CaO clinker was discussed.

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The Effect of Sintering Temperature on Electronic Conductivity of LiFeGdPO4/C as a Lithium-Ion Battery Cathode

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1028.138 ◽

2021 ◽

Vol 1028 ◽

pp. 138-143

Author(s):

Iman Rahayu ◽

Anggi Suprabawati ◽

Vina M. Puspitasari ◽

Sahrul Hidayat ◽

Atiek Rostika Noviyanti

Keyword(s):

Lithium Ion Battery ◽

Reduction Method ◽

Sintering Temperature ◽

Electronic Conductivity ◽

Lithium Ion ◽

Particle Growth ◽

Ion Diffusion ◽

A Value ◽

High Theoretical Capacity ◽

Lithium Ion Diffusion

Lithium ion batteries with LiFePO4 cathode have become the focus of research because they are eco-friendly, stable, high average voltage (3.5 V), and high theoretical capacity (170 mAh/g). However, LiFePO4 has disadvantages such as low electrical conductivity (~10-9 S/cm) and low lithium ion diffusion coefficient (~10-14-10-15 cm2/s) that can inhibit its application as a lithium ion battery cathode material. To increase the electronic conductivity of LiFePO4, it can be done by adding carbon as a coating material, then doping gadolinium metal ions because it has a radius similar to Fe, and increasing sintering temperature. Optimizing the sintering temperature can control particle growth and research was study the sintering temperature of the electronic conductivity of LiFeGdPO4/C and obtain the optimum sintering temperature at LiFeGdPO4/C. The carbothermal reduction method used in synthesis, with a variation of sintering temperature of 800°C, 830°C, 850°C, 870°C, and 900°C using reagents LiH2PO4, Fe2O3, Gd2O3, and carbon black. Furthermore the samples were characterized using XRD, SEM-EDS, and four-point probes. The results of the study were expected to increase the conductivity of LiFePO4. The results show the effect of sintering temperature can increase the electronic conductivity of LiFeGdPO4/C. Samples with a sintering temperature 850°C have the highest conductivity among all temperature variations with a value of 1.11 × 10-5 S cm-1.

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Effect of Reducing Agent on Solution Synthesis of Li3V2(PO4)3 Cathode Material for Lithium Ion Batteries

Molecules ◽

10.3390/molecules25163746 ◽

2020 ◽

Vol 25 (16) ◽

pp. 3746 ◽

Cited By ~ 2

Author(s):

Ali Yaghtin ◽

Seyyed Morteza Masoudpanah ◽

Masood Hasheminiasari ◽

Amirhossein Salehi ◽

Dorsasadat Safanama ◽

...

Keyword(s):

Citric Acid ◽

Oxalic Acid ◽

Electronic Conductivity ◽

Specific Capacity ◽

Synthesis Method ◽

Lithium Ion ◽

Cycling Performance ◽

Reducing Agents ◽

Solution Synthesis ◽

Good Agreement

In this study, Li3V2(PO4)3 (LVP) powders are prepared by a solution synthesis method. The effects of two reducing agents on crystal structure and morphology and electrochemical properties are investigated. Preliminary studies on reducing agents such as oxalic acid and citric acid, are used to reduce the vanadium (V) precursor. The oxalic acid-assisted synthesis induces smaller particles (30 nm) compared with the citric acid-assisted synthesis (70 nm). The LVP powders obtained by the oxalic acid exhibit a higher specific capacity (124 mAh g−1 at 1C) and better cycling performance (122 mAh g−1 following 50 cycles at 1C rate) than those for the citric acid. This is due to their higher electronic conductivity caused by carbon coating and downsizing the particles. The charge-discharge plateaus obtained from cyclic voltammetry are in good agreement with galvanostatic cycling profiles.

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Facile synthesis of Uniform N-doped Carbon-Coated TiO2 Hollow Spheres with Enhanced Lithium Storage Performances

Nanoscale ◽

10.1039/d0nr07659g ◽

2021 ◽

Author(s):

Mengna Fan ◽

Zhonghu Yang ◽

Zhihua Lin ◽

Xunhui Xiong

Keyword(s):

Carbon Coating ◽

Hollow Spheres ◽

Lithium Ion ◽

Rate Performance ◽

Facile Synthesis ◽

Lithium Storage ◽

The Poor ◽

Carbon Coated ◽

Tio2 Hollow Spheres ◽

Tio2 Anode

Great efforts, such as nano-structuring and carbon coating, have been devoted to addressing the poor rate performance of TiO2 anode in lithium ion battery, which is mainly caused by the...

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Synthesis and Electrochemical Properties of Cu-Doped LiMnPO4/C Nanorods as Cathode Materials of Lithium-Ion Batteries

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.25.1 ◽

2013 ◽

Vol 25 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Lin Feng Yuan ◽

Lan Lan Ge ◽

Yu Hua Shen ◽

Hui Zhang ◽

Cui Ping Wang ◽

...

Keyword(s):

Lithium Ion Batteries ◽

Carbon Coating ◽

Electronic Conductivity ◽

Lithium Ion ◽

Solvothermal Process ◽

Initial Discharge Capacity ◽

Initial Discharge ◽

Potential Applications ◽

20 Nm ◽

Physical And Chemical

LiCuxMn1-xPO4/C nanorods are successfully prepared by a simple solvothermal process followed by calcination of the precursor LiCuxMn1-xPO4 and sucrose. The effects of dopant and carbon coating on the physical and chemical characteristics of LiMnPO4 are investigated. The results show that Cu successfully entered into the lattice of LiMnPO4, and induced a decrease in the lattice parameters. A thin layer of carbon coating with an average thickness of 20 nm is formed on the surface of LiCuxMn1-xPO4 particle. We also observe that the LiCuxMn1-xPO4/C nanorods have higher electronic conductivity (5.5139×10-4S cm-1) and initial discharge capacity (87.5 mAh g-1 at 0.5C) compared with pristine LiMnPO4. Based on the results above, the developed nanocomposites could have potential applications in lithium-ion batteries.

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