Co-reporter:Rong Xu, Yan Wu, Xunying Wang, Jing Zhang, ... Bin Zhu
International Journal of Hydrogen Energy 2017 Volume 42, Issue 27(Volume 42, Issue 27) pp:
Publication Date(Web):6 July 2017
DOI:10.1016/j.ijhydene.2017.05.218
•Natural CuFe-oxide mineral (CF) was used as a novel electrolyte.•CF fuel cell demonstrates a power density of 281.25 mW/cm2 at 550 °C.•CF–YSZ nanocomposite exhibits a greatly enhanced ionic conductivity at low temperature.•CF–YSZ nanocomposite fuel cell shows maximum power density of 562.5 mW/cm2.We report for the first time that the commercial yttrium stabilized zirconia (YSZ) nanocomposite with a natural CuFe-oxide mineral (CF) exhibits a greatly enhanced ionic conductivity in the low temperature range (500–600 °C), e.g. 0.48 S/cm at 550 °C. The CF–YSZ composite was prepared via a nanocomposite approach. Fuel cells were fabricated by using a CF–YSZ electrolyte layer between the symmetric electrodes of the Ni0.8Co0.2Al0.5Li (NCAL) coated Ni foam. The maximum power output of 562 mW/cm2 has been achieved at 550 °C. Even the CF alone to replace the electrolyte the device reached the maximum power of 281 mW/cm2 at the same temperature. Different ion-conduction mechanisms for YSZ and CF–YSZ are proposed. This work provides a new approach to develop natural mineral composites for advanced low temperature solid oxide fuel cells with a great marketability.
Co-reporter:Yanyan Liu, Yan Wu, Wei Zhang, Jing Zhang, ... Bin Zhu
International Journal of Hydrogen Energy 2017 Volume 42, Issue 27(Volume 42, Issue 27) pp:
Publication Date(Web):6 July 2017
DOI:10.1016/j.ijhydene.2017.01.039
•Natural CuFe2O4 demonstrated impressive catalytic activity for ORR.•Three types of fuel cell devices were studied.•The conduction mechanism for three types of fuel cell devices was proposed.•The peak power density of the optimal device reached up to 587 mW/cm2 at 550 °C.Natural mineral, cuprospinel (CuFe2O4) originated from natural chalcopyrite ore (CuFeS2), has been used for the first time in low temperature solid oxide fuel cells. Three different types of devices are fabricated to explore the optimum application of CuFe2O4 in fuel cells. Device with CuFe2O4 as a cathode catalyst exhibits a maximum power density of 180 mW/cm2 with an open circuit voltage 1.07 V at 550 °C. And a power output of 587 mW/cm2 is achieved from the device using a homogeneous mixture membrane of CuFe2O4, Li2O-ZnO-Sm0.2Ce0.8O2 and LiNi0.8Co0.15Al0.05O2. Electrochemical impedance spectrum analysis reveals different mechanisms for the devices. The results demonstrate that natural mineral, chalcopyrite, can provide a new implementation to utilize the natural resources for next-generation fuel cells being cost-effective and make great contributions to the environmentally friendly sustainable energy.
Co-reporter:Xunying Wang, Muhammad Afzal, Hui Deng, Wenjing Dong, ... Bin Zhu
International Journal of Hydrogen Energy 2017 Volume 42, Issue 27(Volume 42, Issue 27) pp:
Publication Date(Web):6 July 2017
DOI:10.1016/j.ijhydene.2017.05.158
•Electrolyte layer is replaced by La0.1SrxCa0.9−xMnO3−δ-Sm0.2Ce0.8O1.9 composite.•Investigate the influence of Sr content in the LSCM on the SOFC performances.•Study the effect of the ratio between LSCM and SDC on the SOFC performances.•The novel SOFCs showed OCV over 1.0 V.•The Pmax is 800 mW cm−2 at 550 °C for the La0.1Sr0.9MnO3−δ:SDC with 2:3 (w:w).Lowering the operating temperature of the solid oxide fuel cells (SOFCs) is one of the world R&D tendencies. Exploring novel electrolytes possessing high ionic conductivity at low temperature becomes extremely important with the increasing demands of the energy conversion technologies. In this work, perovskite La0.1SrxCa0.9−xMnO3−δ (LSCM) materials were synthesized and composited with the ionic conductor Sm0.2Ce0.8O1.9 (SDC). The LSCM–SDC composite was sandwiched between two nickel foams coated with semiconductor Ni0.8Co0.15Al0.05LiO2−δ (NCAL) to form the fuel cell device. The strontium content in the LSCM and the ratios of LSCM to SDC in the LSCM-SDC composite have significant effects on the electrical properties and fuel cell performances. The best performance has been achieved from LSCM-SDC composite with a weight ratio of 2:3. The fuel cells showed OCV over 1.0 V and excellent maximum output power density of 800 mW cm−2 at 550 °C. Device processes and ionic transport processes were also discussed.
Co-reporter:Jing Zhang, Wei Zhang, Rong Xu, Xunying Wang, ... Yan Wu
International Journal of Hydrogen Energy 2017 Volume 42, Issue 34(Volume 42, Issue 34) pp:
Publication Date(Web):24 August 2017
DOI:10.1016/j.ijhydene.2017.01.163
•Natural CuFe-oxide mineral (CF) was used as a novel electrolyte.•The output of fuel cell was obviously affected by the compaction pressures.•A maximum power density of 637 mW cm−2 was achieved with the optimal compaction pressure.•Ionic conduction could be efficiently realized via maximum contact and optimized continuous paths.In this study, a new functional composite based on CuFe-oxide mineral (CF) was prepared. This material was first investigated as a novel electrolyte material for low-temperature solid oxide fuel cells (LTSOFCs). The CF and an oxygen ion conducting LixZnO–Sm0.2Ce0.8O2−δ (LZSDC) composite were prepared via a solid-phase blending method. The fuel cell device was fabricated by using the CF–LZSDC composite as an electrolyte layer sandwiched between symmetric electrodes of Ni0.8Co0.2Al0.5Li (NCAL) coated Ni foam. The results showed that device performance increased with increasing compaction pressure. When the compaction pressure was 450 MPa, the maximum output power was 637 mW cm−2, and the lowest ohmic resistance was 0.58 Ω. The electrochemical catalytic activity and the optimal design of LTSOFCs based on the mineral composite materials were investigated.
Co-reporter:Bao Dong;Xinxin Yu;Zhifang Dong;Xiang Yang
Journal of Sol-Gel Science and Technology 2017 Volume 82( Issue 1) pp:167-176
Publication Date(Web):03 January 2017
DOI:10.1007/s10971-016-4297-4
ZnO nanoparticle photocatalysts with a grain size range of 20–100 nm were prepared via a simple sol–gel method and characterized by X-ray powder diffractometry, scanning electron microscopy, gas adsorption, photoluminescence, UV-visible diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. As-synthesized ZnO samples were highly crystallized with hexagonal wurtzite structure, and the grain size was between 20 and 100 nm and increased with the annealing temperature. It was found that the band gap of ZnO nanoparticles narrowed to visible light region, i.e., ~ 2.69 eV, which increased with the calcining temperature. The sample with a high concentration of oxygen vacancy exhibits excellent photocatalytic activity toward methylene blue (MB) degradation under solar light irradiation, at which the highest photodegradation with a react constant k value of 0.12 min−1 was achieved. In addition, MB solution was decomposed within 30 min, and after 9 cycles, the catalyst maintains more than 95% photodegradation. Moreover, the intermediate process experiment demonstrated that •O2− and h+ are the main active intermediate species during the photocatalytic processes.Open image in new window
Co-reporter:Yan Wu;Chen Xia;Wei Zhang;Xiang Yang;Zheng Yu Bao;Jiao Jun Li;Bin Zhu
Advanced Functional Materials 2016 Volume 26( Issue 6) pp:938-942
Publication Date(Web):
DOI:10.1002/adfm.201503756
Natural hematite ore is used as a novel electrolyte material for advanced solid oxide fuel cells (SOFCs). This hematite-based system exhibits a maximum power density of 225 mW cm−2 at 600 °C and reaches 467 mW cm−2 when the hematite is mixed with perovskite-structured La0.6Sr0.4Co0.2Fe0.8O3–δ. These results demonstrate that natural materials for next-generation SOFCs can influence the multiutilization of natural resources, thereby affecting the environment and energy sustainability.
Co-reporter:Chen Xia, Yixiao Cai, Yue Ma, Baoyuan Wang, Wei Zhang, Mikael Karlsson, Yan Wu, and Bin Zhu
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 32) pp:20748
Publication Date(Web):August 2, 2016
DOI:10.1021/acsami.6b05694
Solid oxide fuel cells (SOFCs) have attracted much attention worldwide because of their potential for providing clean and reliable electric power. However, their commercialization is subject to the high operating temperatures and costs. To make SOFCs more competitive, here we report a novel and attractive nanocomposite hematite–LaCePrOx (hematite–LCP) synthesized from low-cost natural hematite and LaCePr-carbonate mineral as an electrolyte candidate. This heterogeneous composite exhibits a conductivity as high as 0.116 S cm–1 at 600 °C with an activation energy of 0.50 eV at 400–600 °C. For the first time, a fuel cell using such a natural mineral-based composite demonstrates a maximum power density of 625 mW cm–2 at 600 °C and notable power output of 386 mW cm–2 at 450 °C. The extraordinary ionic conductivity and device performances are primarily attributed to the heterophasic interfacial conduction effect of the hematite–LCP composite. These superior properties, along with the merits of ultralow cost, abundant storage, and eco-friendliness, make the new composite a highly promising material for commercial SOFCs.Keywords: heterogeneous nanocomposite; interfacial conduction; natural hematite; rare-earth LCP-carbonate mineral; SOFCs
Co-reporter:Y. Wu;B. Shi;W. Ge;C. J. Yan;X. Yang
JOM 2015 Volume 67( Issue 2) pp:361-368
Publication Date(Web):2015 February
DOI:10.1007/s11837-014-1212-8
The relation between the magnetic separation behavior and magnetic properties of a low-grade manganese ore was analyzed before and after treatment by direct reduction with coal. It was found that raw ore with an initial average grade of 10.39% Mn and consisting of diamagnetic and paramagnetic minerals can be concentrated by high-intensity magnetic separation to produce a salable product with a grade of 22.75% Mn and a recovery of 89.88%. In contrast, direct reduction of the ore results in a new Mn-Fe oxide phase formed with a combination of ferromagnetic and paramagnetic properties, thereby increasing the magnetic susceptibilities of the ore by almost two orders of magnitude. The grade of Mn for the roasted ore could only be concentrated to 15.49% with a recovery of 66.67%. Therefore, it is concluded that the low-grade manganese ores with antiferromagnetic and paramagnetic (or diamagnetic, but not strongly ferromagnetic) properties could be efficiently beneficiated via high-intensity magnetic separation.
Co-reporter:Linqin Wang, Yan Wu, Fangyuan Chen, Xiang Yang
Progress in Natural Science: Materials International 2014 Volume 24(Issue 1) pp:6-12
Publication Date(Web):February 2014
DOI:10.1016/j.pnsc.2014.01.002
Hybridization of Mg-doped ZnO and reduced graphene oxide (MZO–RGO) were synthesized through one pot reaction process. Crystallization of MZO–RGO upon thermal decomposition of the stearate precursors was investigated by X-ray diffraction technique. XRD studies point toward the particles size with 10–15 nm, which was confirmed by transmittance electronic microscopy, and also indicates that graphene oxide has been directly reduced into its reduced state graphene during the synthesis. Graphene hybridized MZO photocatalyst showed enhanced catalytic activity for the degradation of methylene blue (MB). The degree of photocatalytic activity enhancement strongly depended both on the coverage of graphene on the surface of MZO nanoparticles and the Mg doping concentration. The sample of 2 wt% graphene hybridized 5 at% Mg-doped ZnO showed the highest photocatalytic activity, which remained good photocatalytic activity after nine cycling runs.
Co-reporter:Yan Wu;Jin Yun;Linqin Wang ;Xiang Yang
Crystal Research and Technology 2013 Volume 48( Issue 3) pp:145-152
Publication Date(Web):
DOI:10.1002/crat.201200438
Abstract
Mg-doped ZnO (MgxZn1-xO) nanoparticles with precise stoichiometry are synthesized through polyacrylamide polymer method. Calcination of the polymer precursor at 650 °C gives particles of the homogeneous solid solution of the (MgxZn1-xO) system in the composition range (x < 0.15). ZnO doping with Mg causes shrinkage of lattice parameter c. The synthesized MgxZn1-xO nanoparticles are typically with the diameter of 70–85 nm. Blue shift of band gap with the Mg-content is demonstrated, and photoluminescence (PL) from ZnO has been found to be tunable in a wide range from green to blue through Mg doping. The blue-related PL therefore appeared to be caused by energetic shifts of the valence band and/or the conduction band of ZnO. MgxZn1-xO nanoparticles synthesized by polyacrylamide-gel method after modified by polyethylene glycol surfactant have a remarkable improvement of stability in the ethanol solvent, indicating that these MZO nanoparticles could be considered as the candidate for the application of solution–processed technologies for optoelectronics at ambient temperature conditions.
Co-reporter:Yan Wu, Mei Fang, Lvdeng Lan, Ping Zhang, K.V. Rao, Zhengyu Bao
Separation and Purification Technology 2012 Volume 94() pp:34-38
Publication Date(Web):19 June 2012
DOI:10.1016/j.seppur.2012.04.008
Biomass is a renewable and carbon neutral solid fuel. Utilization of biomass in iron ore roasting process as heating agent and reducing agent contributes to energy conservation and emission reduction, and can partially replace for coal and coke. The biomass instead of coke was mixed together with iron ore powder from the north of Hainan province into ball roasting process to investigate the effects of mixture composition, reduction temperature, reaction time, the thermal reduction and magnetic properties of the mixture. The results show that the reduction temperature, reaction time and dosage of the biomass are correlated to the quality of the reduction and the magnetism of the iron ore, within the experimental conditions. The mechanism of the biomass reducing the weakly magnetic goethite into stronger magnetic iron oxide has been discussed. The results show that the goethite ores is dramatically reduced and magnetized by about 20 wt.% biomass at low roasting temperature. Application of biomass energy in iron ores roasting process is prospective to the effective use of biomass and for decreasing the consumption of fossil fuels in the steelmaking process.Highlights► A novel direct reduction technology using biomass in goethite ores is presented. ► The effect reducing temperature is less than 650 °C. ► Goethite ore is directed reduced by biomass and converted into maghemite. ► The magnetization of product shows 96% ferromagnetic, Ms of 25.9 emu/g. ► The magnetic susceptibility of product is enhanced more than 30 times.
Co-reporter:Yan Wu, Mei Fang, Lvdeng Lan, Ping Zhang, K.V. Rao, Zhengyu Bao
Separation and Purification Technology (19 June 2012) Volume 94() pp:34-38
Publication Date(Web):19 June 2012
DOI:10.1016/j.seppur.2012.04.008
Biomass is a renewable and carbon neutral solid fuel. Utilization of biomass in iron ore roasting process as heating agent and reducing agent contributes to energy conservation and emission reduction, and can partially replace for coal and coke. The biomass instead of coke was mixed together with iron ore powder from the north of Hainan province into ball roasting process to investigate the effects of mixture composition, reduction temperature, reaction time, the thermal reduction and magnetic properties of the mixture. The results show that the reduction temperature, reaction time and dosage of the biomass are correlated to the quality of the reduction and the magnetism of the iron ore, within the experimental conditions. The mechanism of the biomass reducing the weakly magnetic goethite into stronger magnetic iron oxide has been discussed. The results show that the goethite ores is dramatically reduced and magnetized by about 20 wt.% biomass at low roasting temperature. Application of biomass energy in iron ores roasting process is prospective to the effective use of biomass and for decreasing the consumption of fossil fuels in the steelmaking process.Highlights► A novel direct reduction technology using biomass in goethite ores is presented. ► The effect reducing temperature is less than 650 °C. ► Goethite ore is directed reduced by biomass and converted into maghemite. ► The magnetization of product shows 96% ferromagnetic, Ms of 25.9 emu/g. ► The magnetic susceptibility of product is enhanced more than 30 times.
Co-reporter:Zhifang Dong, Yan Wu
Journal of Photochemistry and Photobiology A: Chemistry (1 March 2017) Volume 336() pp:156-163
Publication Date(Web):1 March 2017
DOI:10.1016/j.jphotochem.2016.12.022
![Glycine,N-[2-[[[(4,5-dimethoxy-2-nitrophenyl)methoxy]carbonyl]amino]ethyl]-N-[[6-[(4-methoxybenzoyl)amino]-9H-purin-9-yl]acetyl]-](http://img.cochemist.com/ccimg/864300/864288-99-3.png)
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![Glycine,N-[2-[[[(4,5-dimethoxy-2-nitrophenyl)methoxy]carbonyl]amino]ethyl]-N-[[4-[(4-methoxybenzoyl)amino]-2-oxo-1(2H)-pyrimidinyl]acetyl]-](http://img.cochemist.com/ccimg/864300/864288-97-1.png)
![Glycine,N-[2-[[[(4,5-dimethoxy-2-nitrophenyl)methoxy]carbonyl]amino]ethyl]-N-[[4-[(4-methoxybenzoyl)amino]-2-oxo-1(2H)-pyrimidinyl]acetyl]-](http://img.cochemist.com/ccimg/864300/864288-97-1_b.png)
![Glycine,N-[(3,4-dihydro-5-methyl-2,4-dioxo-1(2H)-pyrimidinyl)acetyl]-N-[2-[[[(4,5-dimethoxy-2-nitrophenyl)methoxy]carbonyl]amino]ethyl]-](http://img.cochemist.com/ccimg/864300/864288-95-9.png)
![Glycine,N-[(3,4-dihydro-5-methyl-2,4-dioxo-1(2H)-pyrimidinyl)acetyl]-N-[2-[[[(4,5-dimethoxy-2-nitrophenyl)methoxy]carbonyl]amino]ethyl]-](http://img.cochemist.com/ccimg/864300/864288-95-9_b.png)
