BaZr0. 1Ce0. 7Y0. 2O3-delta-SnO2-based composite electrolyte material and semiconductor ion fuel cell

Abstract

The invention discloses a BaZr < 0.1 > Ce < 0.7 > Y < 0.2 > O < 3-delta-SnO < 2 > based composite electrolyte material and a semiconductor ion fuel cell. Belongs to the technical field of solid oxide fuel cells. Wherein the composite electrolyte material is used as an electrolyte of the semiconductor ion fuel cell, the composite electrolyte material is obtained by mixing BaZr0. 1Ce0. 7Y0. 2O3-delta (BZCY) and SnO2, and the mass ratio of the BZCY to the SnO2 is (6-9): (1-4). According to the invention, the proton conduction characteristic of BZCY is combined, and the melting point temperature of Li2CO3 / LiOH can be reduced by utilizing the synergistic effect of wide-band-gap N-type semiconductors SnO2 and NCAL-BZCY-SnO2-based electrolyte composite materials, so that the MPD of the fuel cell also reaches 92.19 mW / cm < 2 > at the low temperature of 350 DEG C, and the low-temperature development of the fuel cell is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of solid oxide fuel cells, and more specifically, to a BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Based composite electrolyte materials and semiconductor ion fuel cells. Background Art

[0002] As global energy and environmental issues become increasingly severe, it is a general trend to vigorously develop high-efficiency, pollution-free solid oxide fuel cells (SOFCs). SOFC is one of the electrochemical energy conversion devices, with the advantages of all components being solid, high energy conversion efficiency and no pollution. Traditional SOFCs have a high operating temperature of 600-1000℃, which leads to problems such as long startup time and poor stability.

[0003] Semiconductor ion fuel cell (SIFC) is a SOFC that uses a semiconductor and ion conductor composite as the electrolyte. The internal heterogeneous structure of the electrolyte improves the electrochemical performance of the battery at low temperatures (450-600°C) and is considered to be a potential battery for commercialization.

[0004] In the prior art, when the operating temperature of SIFC is reduced to 419°C or lower, the Li 2 CO 3 / LiOH solidification will cause the constructed heterostructure interface to lose the ability to accelerate interfacial ion transport. At the same time, the electrode material of SIFC will also be affected by Li 2 CO 3 / The solidification of LiOH causes the failure of the electrode catalytic activity of the battery, resulting in a serious problem that the fuel cannot operate.

[0005] Therefore, finding new solid oxide fuel cell electrolyte materials and further reducing the operating temperature of the battery is an urgent problem that needs to be solved. Summary of the invention

[0006] In view of this, one of the purposes of the present invention is to provide a composite electrolyte material suitable for semiconductor ion fuel cells. When used as an electrolyte for solid oxide fuel cells, an excellent MPD of 1102 mW / cm2 was obtained at 550°C. 2 , Li 2 CO 3The melting point of the LiOH complex was reduced from 419°C to 407°C, which resulted in the MPD of the fuel cell reaching 92.19 mW / cm at a low temperature of 350°C. 2 ; This is conducive to the low-temperature development of fuel cells, thereby further improving the green energy characteristics of fuel cells.

[0007] To achieve the above object, the technical solution of the present invention is: A kind of BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Based composite electrolyte material, the composite electrolyte material is used as an electrolyte of a semiconductor ion fuel cell, the composite electrolyte material is composed of BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 Mixed to obtain the BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 The mass ratio is 6~9:1~4.

[0008] Here, δ is a value that allows the compound to maintain electrical neutrality.

[0009] Furthermore, the BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 The mass ratio is 7~9:1~3, specifically including 9:1, 8:2, 7:3, and 6:4.

[0010] Furthermore, the BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 The mass ratio is 7:3.

[0011] A second object of the present invention is to provide a method for preparing the above-mentioned composite electrolyte material, comprising the following steps: (1) Weigh BaZr and 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 ; (2) BaZr 0.1 Ce 0.7 Y 0.2 O3-δ and SnO 2 The mixture is placed in a ball mill, and anhydrous ethanol is added for ball milling and mixing to obtain a mixed slurry; (3) drying the mixed slurry to remove anhydrous ethanol to obtain a dried mixed slurry; (4) The dried mixed slurry is subjected to primary grinding, sintering, and secondary grinding to obtain BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Composite electrolyte materials.

[0012] Furthermore, in step (2), the rotation speed of the ball mill is 150-200 r / min, and the ball milling time is 5-7 h; in step (3), the mixed slurry is placed under a heating lamp for drying, and the drying time is 3-4 h; in step (4), the first grinding time is 30-60 min, the sintering temperature is 550-650°C, the sintering time is 4-6 h, and the second grinding time is 30-60 min.

[0013] Furthermore, in step (1), the BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ The preparation method comprises: S1. Weigh the raw materials Ba(NO 3 ) 2 、Zr(NO 3 ) 2 ·5H 2 O、Ce(NO 3 ) 3 6H 2 O、Y(NO 3 ) 3 6H 2 O, placed in a container and stirred to dissolve, then added citric acid CA and continued to stir; then added a certain amount of EDTA, and added ammonia water to adjust the pH value to 6.5-7; wherein the molar ratio of EDTA to citric acid CA and metal cation is 1:1.5:1.

[0014] S2. Place the container in a water bath and heat it. After the solution becomes gelatinous, place the container in a drying oven and dry it until it is completely dry. S3, the dried material is subjected to first grinding, pre-sintering, second grinding, sintering, and third grinding to obtain BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ powder; Wherein, in step S2, the water bath heating temperature is 75-90°C, the rotation speed is 10 r / min, the drying temperature is 180-220°C, and the drying time is 2-4 h; In step S3, the time of the first grinding, the second grinding and the third grinding is 30-60 min, the temperature and time of the pre-sintering are 600° C. and 5 h respectively, and the sintering temperature is 800-1300° C.; Preferably, the sintering temperature is 1200° C. and the sintering time is 10 h.

[0015] Furthermore, in step (1), the SnO 2 The preparation method comprises: S1. Add tin nitrate to a container, and then place it on a magnetic stirrer to fully stir and dissolve it in water, wherein the solid-liquid ratio of tin nitrate to water is 1g: 20-40 mL, and then add citric acid CA and continue stirring; then add a certain amount of EDTA, and add ammonia water to adjust the pH value to 6.5-7; wherein the molar ratio of EDTA to citric acid CA and metal cation is 1:1.5:1; S2. Place the container in a water bath for constant temperature treatment at a temperature of 75-95°C and a rotation speed of 10 r / min. After the solution becomes gelatinous, place it in a drying oven for drying. The drying temperature is 180-210°C. S3, the dried material was placed in a ceramic crucible and ground for 30-60 min, then placed in a muffle furnace and pre-sintered at 500-550°C for 5-7 h; after pre-sintering, it was ground in a mortar for 30-60 min, and then sintered at 500-800°C for 8-12 h; after sintering, it was ground again in a mortar for 30-60 min to obtain SnO 2 Powder.

[0016] The tin dioxide precursor is obtained by a sol-gel method, and is simultaneously combined with ultrasonic treatment, spray drying, and subsequent multiple grinding and sintering to make the prepared tin dioxide have higher purity and smaller particle size.

[0017] The present invention also aims to provide a method comprising providing a BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Semiconductor ion fuel cells based on composite electrolyte materials.

[0018] In the present invention, the electrode material of the semiconductor ion fuel cell is LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCAL), the LiNi0.8 Co 0.15 Al 0.05 O 2 It is obtained by a solid phase mixing method, wherein the sintering temperature after mixing is 810°C and the time is 10 h.

[0019] The semiconductor ion fuel cell composed of the present invention can fully utilize the P-type semiconductor BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ Proton conduction properties, electrode materials and composite electrolyte materials work together, namely NCAL-BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 The synergistic effect of the complex can reduce Li 2 CO 3 / LiOH melting point, and BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 The composite electrolyte forms a PN heterojunction at the contact interface. The invention successfully maintains the rapid conduction of the proton conduction mechanism at the interface, jointly promoting and ensuring the low-temperature operation of the battery.

[0020] Specifically, LiNi 0.8 Co 0.15 Al 0.05 O 2 The preparation method comprises: (1) According to the ion molar ratio of Li: Ni: Co: Al = 1: 0.8: 0.15: 0.05, weigh a certain amount of lithium hydroxide monohydrate, nickel hydroxide, cobalt tetroxide and aluminum trioxide respectively; put the weighed materials into a ball mill, add a proper amount of alcohol, and put them into a ball mill with a set program for complete ball milling; after the ball milling is completed, the liquid in the ball mill is sucked out with a syringe and transferred into a large beaker, and the residual material in the ball mill is properly cleaned with alcohol again and sucked into the large beaker, and the large beaker is placed under a drying lamp for drying; wherein, the ball mill is set to have a speed and time of 280 r / min and 6 h respectively; the drying time of the drying lamp is 3 h; (2) Grind the dried solid material in a mortar manually for about 1 h, then pour the ground material into a clean crucible and pre-sinter it in a muffle furnace; the pre-sintering temperature and pre-sintering time are 500 °C and 5 h, respectively; (3) The pre-sintered material was placed in a mortar and ground manually again. After 1 h, the powder was placed in a crucible again and sintered again using a muffle furnace. The sintering temperature and time were 810 °C and 10 h, respectively.

[0021] Compared with the prior art, the present invention has the following advantages: The innovation of the present invention is that it can make full use of the P-type semiconductor BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ Proton conduction properties, NCAL-BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 The synergistic effect of the composite (i.e., the electrode material and the composite electrolyte material cooperate with each other) can reduce the Li 2 CO 3 / LiOH melting point, and BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 The composite electrolyte forms a PN heterojunction at the contact interface, and the invention successfully maintains the rapid conduction of the proton conduction mechanism at the interface. The experimental results show that the optimal ratio of 7BaZr designed by the invention 0.1 Ce 0.7 Y 0.2 O 3-δ -3SnO 2 Composite electrolyte material, the battery achieved an excellent MPD of 1102 mW / cm at 550°C 2 , open circuit voltage (OCV) is 1.147 V, ohmic resistance (R 0 ) is 0.137Ω·cm 2 , than BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ The single cell power of the electrolyte (800 mW·cm -2 ) increased by 38%, and the MPD at 350℃ reached 92.19 mW / cm 2 , that is, the composite electrolyte material provided by the present invention can enable the battery to operate at a minimum temperature of 350°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 (a) BaZr prepared by sol-gel method 0.1 Ce 0.7 Y 0.2 O3-δ (BZCY) is the XRD of sintered at 800℃, 900℃ and 1000℃ for 10h, and (b) is the XRD of sintered at 1100℃, 1200℃ and 1300℃ for 10h.

[0023] Figure 2 (a) BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY), SnO 2 and 7BZCY–3SnO 2 (a) XRD patterns of mixed electrolytes with different proportions.

[0024] Figure 3 In SnO 2 (a) IV / IP curve of a single cell with electrolyte under multiple reverse connection at a test temperature of 550°C; (b) EIS curve.

[0025] Figure 4 (a) BaZr with different mass ratios 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY) and SnO 2 I–V / I–P curves of the battery with composite electrolyte at 550°C; (b) 7BZCY:3SnO 2 I–V / I–P curves of a single cell with BZCY as electrolyte at a test temperature of 350–550°C. (c) I–V / I–P curves of a single cell with BZCY as electrolyte at a test temperature of 375–550°C.

[0026] Figure 5 In the experiment, BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY) and SnO 2 EIS curve of the battery with the composite as electrolyte at 550 °C.

[0027] Figure 6 In the middle, it is 7BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY): 3SnO 2 TG and DSC diagrams before and after the test, where (a) before the test; (b) after the test.

[0028] Figure 7 In the middle, it is BaZr 0.1 Ce0.7 Y 0.2 O 3-δ (BZCY) and SnO 2 UV spectra and band gap diagrams, where (a) BZCY; (b) SnO 2 .

[0029] Figure 8 In the middle, it is BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY) and SnO 2 Energy band diagram of PN heterojunction. DETAILED DESCRIPTION

[0030] Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar modifications without violating the connotation of the present invention, so the present invention is not limited to the specific implementation disclosed below.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0032] Example 1 1. The P-type semiconductor BaZr was synthesized by sol-gel method. 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY) electrolyte material, explore the optimal phase formation temperature, the specific preparation steps are as follows: (1) Weigh a certain amount of Ba(NO 3 ) 2 、Zr(NO 3 ) 2 ·5H 2 O、Ce(NO 3 ) 3 6H 2 O、Y(NO 3 ) 3 6H 2 O in a beaker, then add citric acid CA and continue stirring. Then add a certain amount of EDTA, and add ammonia water to adjust the pH value to 7; wherein the molar ratio of EDTA to citric acid CA and metal cation is 1:1.5:1.

[0033] (2) Place the beaker in a water bath and stir the reaction. When the solution becomes gel-like, place the beaker in a drying oven until it is completely dry. Set the water bath temperature to 80°C and the rotation speed to 10 r / min. The heating temperature and time of the drying oven are 210°C and 3 h, respectively.

[0034] (3) The dried material was ground in a mortar for 1 h, then placed in a ceramic crucible and pre-fired in a muffle furnace. The pre-fired temperature and sintering time were 600 °C and 5 h, respectively. After pre-fired, the material was ground again in a mortar for 1 h and then sintered at 800 °C, 900 °C, 1000 °C, 1100 °C, 1200 °C, and 1300 °C, respectively. After sintering, the material was ground again in a mortar for 1 h to obtain a P-type semiconductor BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ Powder.

[0035] In order to prepare a P-type semiconductor BaZr with a pure phase structure 0.1 Ce 0.7 Y 0.2 O 3-δ In the above steps, the P-type semiconductor BaZr was prepared by sol-gel method. 0.1 Ce 0.7 Y 0.2 O 3-δ The electrolyte powder was sintered at 800℃, 900℃, 1000℃, 1100℃, 1200℃, and 1300℃ for 10 h and then subjected to XRD test. Figure 1 As shown in the figure, when the sintering temperature is 800℃, the XRD of the P-type semiconductor BZCY corresponds basically to the standard PDF card PDF#75-0431, and the (200) crystal plane still has the phenomenon of peak splitting. With the further increase of the sintering temperature, the crystallinity of the P-type semiconductor BZCY becomes better and better and the phenomenon of peak splitting of the (200) crystal plane disappears, and the material presents a single rhombohedral crystal structure. When the sintering temperature is 1200℃, the crystallinity reaches the best, so 1200℃ is the best phase formation temperature for preparing the P-type semiconductor BZCY by the sol-gel method. When the sintering temperature is further increased to 1300℃, the phenomenon of peak splitting appears on both the (200) and (211) crystal planes, indicating that the P-type semiconductor BZCY material has a small amount of monoclinic phase in the rhombohedral crystal matrix. In the experiment of the present invention, the P-type semiconductor BZCY prepared by the sol-gel method with a sintering temperature of 1200℃ is introduced into the electrolyte.

[0036] 2. Preparation of N-type semiconductor SnO 2 , the preparation method is as follows: S1. Add tin nitrate into a container, and then place it on a magnetic stirrer to fully stir and dissolve it in water, wherein the solid-liquid ratio of tin nitrate to water is 1g:30 mL, and then add citric acid CA and continue stirring; then add a certain amount of EDTA, and add ammonia water to adjust the pH value to 7; wherein the molar ratio of EDTA to citric acid CA and metal cation is 1:1.5:1; S2. Place the container in a water bath for constant temperature treatment at a temperature of 75-95°C and a rotation speed of 10 r / min. After the solution becomes gelatinous, place it in a drying oven for drying. The drying temperature is 180-210°C. S3, the dried material was placed in a ceramic crucible and ground for 30-60 min, then placed in a muffle furnace and pre-sintered at 500-550°C for 5-7 h; after pre-sintering, it was ground in a mortar for 30-60 min, and then sintered at 500-800°C for 8-12 h; after sintering, it was ground again in a mortar for 30-60 min to obtain SnO 2 Powder.

[0037] 3. Synthesis of P-type semiconductor BaZr by solid phase mixing method 0.1 Ce 0.7 Y 0.2 O 3-δ With N-type semiconductor SnO 2 The composite electrolyte is prepared by the following method: (1) According to BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ with SnO 2 Different mass ratios (9:1, 8:2, 7:3, 6:4) were weighed using a balance. 0.1 Ce 0.7 Y 0.2 O 3-δ (obtained in step 1 above) and SnO 2 (obtained in step 2 above) are placed in ball mills respectively; an appropriate amount of anhydrous ethanol is added to the ball mill, and the speed and time are set to 180 r / min and 6 h respectively.

[0038] (2) Use a syringe to suck out the evenly mixed raw materials in the ball mill into a beaker, and place it under a baking lamp to dry it in anhydrous ethanol (about 3-4 h); after drying, grind it in a mortar for 1 h and then place it in a muffle furnace to sinter it at 600 °C for 5 h.

[0039] (3) After sintering, the mixture was ground again in a mortar for 1 h to obtain P-type semiconductor BaZr 0.1 Ce 0.7 Y 0.2 O 3-δElectrolyte and N-type semiconductor SnO 2 Composite electrolyte materials.

[0040] The prepared BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ SnO 2 , XRD test of composite electrolyte materials, such as Figure 2 It is a P-type semiconductor BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ , N-type semiconductor SnO 2 And BaZr with different mass ratios 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 The XRD spectrum of the composite is shown in Figure 1. 2 And P-type semiconductor BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ The XRD patterns of the two materials were completely consistent with those of the standard PDF#88-0287 and PDF#75-0431 cards, respectively. The XRD patterns of the two materials after solid phase mixing in a ball mill and sintering at 600°C in a muffle furnace for 5 h completely corresponded to the XRD patterns of the single materials, with no new peaks and obvious phase structure changes. This indicates that the P-type semiconductor BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ With N-type semiconductor SnO 2 It has good chemical compatibility in air at 600°C. 4. Synthesis of LiNi by high temperature solid phase method 0.8 Co 0.15 Al 0.05 O 2 (NCAL) electrode material, the specific preparation method is as follows: (1) According to the ion molar ratio of Li: Ni: Co: Al = 1: 0.8: 0.15: 0.05, weigh a certain amount of Li(OH)·H 2 O、Ni(OH) 2 、Co 3 O 4 and Al 2 O 3. Put the weighed material into the ball mill, add an appropriate amount of alcohol, and put it into the ball mill with the set program for complete ball milling. Set the speed and time to 280 r / min and 8h respectively. After the ball milling is completed, the liquid in the ball mill is sucked out with a syringe and transferred to a large beaker. Use alcohol to properly clean the residual material inside the ball mill and suck it into the large beaker. Place the large beaker under a drying lamp for drying for 3 hours.

[0041] (2) Grind the dried solid material in a mortar manually for about 1 h, then pour the ground material into a clean crucible and pre-sinter it in a muffle furnace with a heating rate of 10 °C min -1 , pre-sintered at 500 °C for 5 h.

[0042] (3) The pre-sintered material was placed in a mortar and ground manually again. After 1 h, the powder was placed in a crucible again and sintered again in a muffle furnace at a sintering temperature of 810 °C and a sintering time of 10 h. NCAL powder was obtained by grinding again.

[0043] 5. Preparation of electrodes. The specific steps are as follows: (1) According to a certain ratio, weigh 10 g of NCAL powder and 0.05 g of PVB in a mortar, mix thoroughly, and then add 2 mL of anhydrous ethanol and 3 mL of pinene alcohol; (2) Use a punch to punch out a nickel foam disc, and evenly apply the slurry prepared in (1) on the nickel foam disc; the area of ​​the punch is 0.64 cm 2 , the thickness of nickel foam is 1.2 mm.

[0044] (3) Wrap the coated nickel foam with tin foil and place it in a 120°C drying oven for 24 min. Repeat the above operation twice, brush the surface of the nickel foam to give it a metallic luster, and then place it in a drying oven to dry, finally obtaining a porous symmetrical electrode material Ni-NCAL, wherein the drying temperature and drying time are 120°C and 30 min, respectively.

[0045] 6. Preparation of single cell In this example, Ni-NCALBaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 The preparation of Ni-NCAL single cell is described below. (1) Place the electrode prepared in step 5 into the bottom of the mold for making the battery. The effective working area of ​​the electrode is 0.64 cm 2 .

[0046] (2) Weigh an appropriate amount (0.30 g-0.35 g) of BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ or BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 The electrolyte is placed on the bottom NCAL electrode and compacted using a mold.

[0047] (3) Then place an NCAL electrode on top of the mold to make the battery.

[0048] (4) Place the mold into a tablet press to connect the electrodes and electrolyte together to obtain a single cell.

[0049] (5) Place the prepared single cell into the test battery fixture and start testing.

[0050] 7. Performance Testing Figure 3 SnO 2 (a) IV / IP curve (b) EIS curve of a single cell with electrolyte at multiple tests at 550°C. The maximum output power density of the battery at 550°C increases with the number of tests, while the impedance decreases. To our surprise, the maximum output power density of the battery reached 800 mW / cm after the third test. 2 , this should be SnO 2 As a result of the unique lithium insertion properties, at 550°C, H 2 Will restore NCAL to generate Li + Due to the potential difference between the electrode and the electrolyte, Li + It will diffuse into SnO 2 The electrolyte and SnO 2 The reaction generates lithium oxide, which then reacts with CO 2 and H 2 O reacts to generate Li 2 CO 3 / LiOH composite, Li at 550℃ 2 CO 3 The Li / LiOH composite is in a molten state, which greatly improves the ionic conductivity of the electrolyte and reduces the activation energy and polarization resistance of the electrode reaction, thereby greatly improving the MPD of the battery.

[0051] Figure 4 The fuel cell was preheated at 550℃ for 30 min to perform a single-cell Ni-NCAL|BaZr 0.1 Ce0.7 Y 0.2 O 3-δ (BZCY)-SnO 2 (pure BZCY / 9:1 / 8:2 / 7:3 / 6:4)|Ni-NCAL electrochemical performance (IV / IP) test and electrochemical impedance spectroscopy (EIS) test such as Figure 5 shown.

[0052] from Figure 4 (c) It can be seen that the single cell with BZCY as electrolyte obtained open circuit voltages of 1.09 V, 1.08 V, 1.08 V, 1.16 V, and 1.18 V at 550°C, 500°C, 450°C, 400°C, and 370°C, respectively, and a power density of 800 mW / cm 2 、650mW / cm 2 , 508 mW / cm 2 、177mW / cm 2 、86 mW / cm 2 MPD, this is because the proton ion radius is smaller than the oxygen ion radius, so H + Conduction has a ratio of O 2− Conducting lower activation energy can achieve higher ionic conductivity under low temperature working conditions, further reducing the operating temperature of the battery to 350°C, at which point the MPD of the battery has dropped to 0 mW / cm 2 This is because the ionic conductivity of the electrolyte and the catalytic activity of the electrode are both at a low level at this operating temperature and the solidified Li 2 CO 3 The / LiOH complex also has a certain blocking effect on ion conductivity. The P-type semiconductor BZCY battery has a good open circuit voltage at all temperatures, and there is no battery short circuit phenomenon. The measured open circuit voltages are 0.18Ω·cm at 550℃, 500℃, 450℃, and 400℃, respectively. 2 , 0.20 Ω·cm 2 , 0.24 Ω·cm 2 , 0.30 Ω·cm 2 Therefore, P-type semiconductor BZCY is feasible as a SOFC electrolyte alone, but the MPD of P-type semiconductor BZCY battery at low temperature needs to be further improved.

[0053] In order to explore the P-type semiconductor BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY) and N-type semiconductor SnO 2The optimal composite ratio was obtained by producing four different mass ratios of P-type semiconductor BZCY and N-type semiconductor SnO 2 Composite electrolytes such as Figure 4 (a), battery 9BZCY:1SnO 2 、8BZCY:2SnO 2 、7BZCY:3SnO 2 、6BZCY:4SnO 2 915.63 mW / cm 2 、957.81mW / cm 2 、1101.56 mW / cm 2 、859.38 mW / cm 2 The excellent MPD of SnO 2 With the increase of the mass ratio, the MPD of the battery showed a trend of increasing first and then decreasing, and reached 1101.56 mW / cm when the mass ratio was 7:3. 2 , the battery is in 9BZCY:1SnO 2 、8BZCY:2SnO 2 、7BZCY:3SnO 2 、6BZCY:4SnO 2 The open circuit voltages of 1.116 V, 1.138 V, 1.147 V, and 1.149 V were obtained, showing a trend of increasing, which indicates that the SnO 2 It has the effect of increasing the open circuit voltage of the battery. The above analysis shows that adding a certain mass ratio of SnO to the P-type semiconductor BZCY 2 It can effectively improve the open circuit voltage and MPD, and BZCY and SnO 2 The best composite mass ratio is 7:3. Figure 4 (b, c), 7BZCY-3SnO with the best ratio designed by the present invention 2 The composite electrolyte achieves an excellent MPD of 1102 mW / cm at 550°C. 2 , open circuit voltage (OCV) is 1.147 V, ohmic resistance (R 0 ) is 0.137 Ω·cm 2 , which is higher than the single cell power of P-type semiconductor BZCY electrolyte (800 mW·cm -2 ) increased by 38%, and the MPD at 350℃ reached 92.19mW / cm 2 .

[0054] In order to prove that Li 2 CO 3 The presence of / LiOH complex has an important effect on 7BZCY:3SnO2 Thermogravimetric analysis was performed before and after the electrolyte test, e.g. Figure 6 Compared with the electrolyte before the test, the DSC of the electrolyte after the test showed an endothermic peak at 407 °C, which should be due to Li 2 CO 3 The melting point of the Li / LiOH complex is 2 CO 3 The melting point of the / LiOH complex was reduced by 12°C, which proves that the composite electrolyte material provided by the present invention and the electrode material have a synergistic effect on reducing the Li 2 CO 3 / LiOH complex melting point, Figure 6 Given Li 2 CO 3 Schematic diagram of the existence area of ​​ / LiOH complex.

[0055] Figure 7 (a, b) are BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ with SnO 2 UV spectrum and band gap diagram of BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ Belongs to P-type semiconductor, SnO 2 It is an N-type semiconductor. When the two materials are combined, charge redistribution will occur at the contact interface of the two materials at the battery operating temperature to form a PN junction. The space charge layer of the PN junction can effectively promote the conduction of oxygen ions and protons while inhibiting the conduction of electrons.

[0056] About BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 UV test, the results are as follows Figure 7 shown.

[0057] According to the following formula, we can calculate BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ with SnO 2 The band gaps are 3.57 eV and 3.86 eV respectively.

[0058]

[0059] The bandgap of BaZr is plotted based on the bandgap of the two materials. 0.1 Ce 0.7 Y0.2 O 3-δ with SnO 2 The PN heterojunction energy band diagram and the model schematic diagram are as follows Figure 8 shown.

[0060] Comparative Example 1 In this embodiment, the single cell is Ni-NCAL|Ce 0.8 Sm 0.2 O 2−δ –SnO 2 |Ni-NCAL.

[0061] The preparation methods of the electrolyte, the electrode and the single cell are the same as those in Example 1.

[0062] The only difference is that in this embodiment, the electrolyte material is Ce 0.8 Sm 0.2 O 2−δ with SnO 2 Composite materials, in which Ce 0.8 Sm 0.2 O 2−δ with SnO 2 The mixing ratio is 8:2.

[0063] After testing, the maximum power density of the single cell prepared in this embodiment can reach 1059 mW / cm at 550°C. 2 , and the lowest operating temperature can only be 500℃, at which time it is 500 mW / cm 2 MPD.

[0064] Comparative Example 2 In this embodiment, the single cell is Ni-NCAL|Gd 0.15 Ni 0.05 Ce 0.8 O 2-δ -SnO 2 |Ni-NCAL. The preparation methods of the electrolyte, the electrode and the single cell are the same as those in Example 1.

[0065] The difference is that in this embodiment, the electrolyte material is LiNi 0.8 Co 0.1 Mn 0.1 O 2-δ with SnO 2 Composite materials, in which LiNi 0.8 Co 0.1 Mn 0.1 O 2-δ with SnO 2 The mixing ratio is 7:3.

[0066] After testing, the maximum power density of the single cell prepared in this embodiment at 550°C is 879.4 mW cm -2 , and the lowest operating temperature can only be 450°C, at which point it is 487.3 mW / cm 2 MPD.

[0067] Comparative Example 3 In this embodiment, the single cell is Ni-NCAL|BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 |Ni–NCAL.

[0068] The preparation methods of the electrolyte, electrodes and single cells are basically the same as those in Example 1.

[0069] The difference is that in this embodiment, the coprecipitation method used in the electrolyte material is used to prepare BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ : S1. Weigh a certain amount of Ba(NO 3 ) 2 、Zr(NO 3 ) 2 ·5H 2 O、Ce(NO 3 ) 3 6H 2 O、Y(NO 3 ) 3 6H 2 O in beaker A and add 100~200 mL of deionized water to fully stir and dissolve. Then weigh a certain amount of anhydrous Na 2 CO 3 Place in beaker B and add 70-100 mL of deionized water and stir thoroughly to dissolve.

[0070] S2. The solution in beaker A is dripped into beaker B at a constant speed and uniformly. At the same time, beaker B is always stirred by a magnetic stirrer. After the solution in beaker A is completely dripped into beaker B, beaker B continues to stir for 2 to 4 hours to allow the two solutions to fully react. Finally, let it stand for 10 to 14 hours to allow the precipitate to be completely separated from the supernatant.

[0071] S3. Filter out the precipitate with a suction bottle equipped with a vacuum pump, wash the precipitate with deionized water and filter it again. Repeat the above steps three times and place the precipitate in a drying oven to dry for 5-7 hours. Grind the dried precipitate in a mortar for 45 minutes, then put it into a ceramic crucible and pre-sinter it in a muffle furnace at 600°C for 5 hours. After pre-sintering, grind it again in a mortar for 45 minutes, and then sinter it at 800°C, 900°C, 1000°C, 1100°C, 1200°C, and 1300°C for 10 hours. After sintering, grind it again in a mortar for 45 minutes to obtain BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ powder.

[0072] In this embodiment, BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ with SnO 2 The mixing ratio is 7:3.

[0073] After testing, the maximum power density of the single cell prepared in this embodiment at 550°C is 1024 mW·cm -2 Its MPD at 350℃ is only 54.64mW / cm 2 .

[0074] Comparative Example 4 In this embodiment, the single cell is Ni-NCAL|BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 |Ni–NCAL.

[0075] The preparation methods of the electrolyte, electrodes and single cells are basically the same as those in Example 1.

[0076] The difference is that in this embodiment, the SnO used in the electrolyte material 2 Prepared by thermal decomposition: S1. Weigh a certain amount of tin nitrate (Sn(NO 3 ) 2 ) in an alumina ceramic crucible. S2. Place in a Ma Furnace and calcine at 500~600℃ for 3~6 hours.

[0077] S3, then grind in a mortar for 1 h to obtain SnO 2 Powder.

[0078] In this embodiment, LiNi 0.8 Co0.1 Mn 0.1 O 2-δ with SnO 2 The mixing ratio is 7:3.

[0079] After testing, the maximum power density of the single cell prepared in this embodiment at 550°C is 1016 mW·cm -2 Its MPD at 350℃ is only 46.22mW / cm 2 .

[0080] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Composite electrolyte materials, It is characterized in that The composite electrolyte material is used as an electrolyte for a semiconductor ion fuel cell. The composite electrolyte material is composed of BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 Mixed to obtain the BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 The mass ratio is 6~9:1~4.

2. BaZr according to claim 1 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Composite electrolyte materials, It is characterized in that The BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 The mass ratio is 7~9:1~3.

3. BaZr according to claim 1 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Composite electrolyte materials, It is characterized in that The BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 The mass ratio is 7:

3.

4. BaZr according to any one of claims 1 to 3 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Preparation method of composite electrolyte material, It is characterized in that The following steps are involved: (1) Weigh BaZr and 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 ; (2) BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ and SnO 2 The mixture is placed in a ball mill, and anhydrous ethanol is added to perform ball milling and mixing to obtain a mixed slurry; (3) drying the mixed slurry to remove anhydrous ethanol to obtain a dried mixed slurry; (4) The dried mixed slurry is subjected to primary grinding, sintering, and secondary grinding to obtain BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Composite electrolyte materials.

5. The preparation method according to claim 4, It is characterized in that In step (2), the rotation speed of the ball mill is 150-200 r / min, and the ball milling time is 5-7 h. In step (3), the mixed slurry is placed under a heating lamp for drying, and the drying time is 3-4 h. In step (4), the first grinding time is 30-60 min, the sintering temperature is 550-650°C, the sintering time is 4-6 h, and the second grinding time is 30-60 min.

6. The preparation method according to claim 4, It is characterized in that In step (1), the BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ The preparation method comprises: S1. Weigh the raw materials Ba(NO 3 ) 2 、Zr(NO 3 ) 2 ·5H 2 O、Ce(NO 3 ) 3 6H 2 O、Y(NO 3 ) 3 6H 2 O, placed in a container and stirred to dissolve, then added citric acid CA and continued to stir; then added a certain amount of EDTA, and added ammonia water to adjust the pH value to 6.5-7; wherein the molar ratio of EDTA to citric acid CA and metal cation is 1:1.5:

1. S2. Place the container in a water bath and heat it. After the solution becomes gelatinous, place the container in a drying oven and dry it until it is completely dry. S3, the dried material is subjected to first grinding, pre-sintering, second grinding, sintering, and third grinding to obtain BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ powder; Among them, in step S2, the temperature of water bath heating is 75~90℃, the rotation speed is 10 r / min, the drying temperature is 180~220℃, and the drying time is 2~4 h; in step S3, the time of the first grinding, the second grinding and the third grinding is 30~60 min, the temperature and time of pre-burning are 600℃ and 5 h respectively, the sintering temperature is 800~1300℃, and the sintering time is 10 h.

7. A method containing BaZr as claimed in any one of claims 1 to 3 0.1 Ce 0.7 Y 0.2 O 3-δ -SnO 2 Semiconductor ion fuel cells based on composite electrolyte materials.

8. The semiconductor ion fuel cell according to claim 7, It is characterized in that The electrode material of the battery is LiNi 0.8 Co 0.15 Al 0.05 O 2 , the LiNi 0.8 Co 0.15 Al 0.05 O 2 It is obtained by a solid phase mixing method, wherein the sintering temperature after mixing is 810°C and the time is 10 h.

Images