Abstract:
An oxygen sensing device with capability of storing energy and releasing energy including an oxygen sensing unit, a gas storing unit, and a control unit. The oxygen sensing unit includes a solid oxide electrolyte disposed between two conductive catalyst layers. The control unit includes a power source, a voltmeter, and a power output circuit. The power source provides electrical power to these conductive catalyst layers of the oxygen sensing unit to process a catalytic reaction and generate hydrocarbons for being stored in the gas storing unit. The voltmeter senses a voltage generated by the oxygen sensing unit when the oxygen sensing unit senses oxygen. The oxygen sensing unit makes the hydrocarbons stored in the gas storing unit and oxygen process a chemical reaction for generating electrical power to the power output circuit. The oxygen sensing unit uses the power source to generate hydrogen or syngas.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The instant disclosure relates to an oxygen sensing device; in particular, to an oxygen sensing device with capability of storing energy and releasing energy utilized for removing pollutants, output electricity, storing electrical energy, and making specific chemicals. 
         [0003]    2. Description of Related Art 
         [0004]      FIG. 1A  shows a schematic diagram of a traditional fuel converting mechanism of a car. The traditional fuel converting mechanism in a car comprises an alternator  10 , an internal combustion engine  11 , a turbine  12 , an oxygen sensing device  13  and a catalytic converter  14 . The internal combustion engine  11  makes the combustion of air and fuel (e.g. hydrocarbons) and generates gas such as carbon dioxide, carbon monoxide, water, and nitrogen monoxide . . . etc. Then, the internal combustion engine  11  outputs the mentioned gas (CO 2 , CO, H 2 O, and NO . . . etc.) to the turbine  12 . The turbine  12  cooperates with the alternator  10  to generate electrical energy. The oxygen sensing device  13  senses the oxygen outputted from the turbine  12  and generates a control signal A/F for adjusting the ratio of the air and the fuel transmitted to the internal combustion engine  11 . The catalytic converter  14  converts the carbon monoxide (CO), hydrogencarbons (HCs) and nitrogen monoxide (NO) outputted from the turbine  12  to carbon dioxide (CO 2 ) and nitrogen (N 2 ) for complying with environmental standards. 
         [0005]      FIG. 1B  shows a schematic diagram of a traditional oxygen sensing device. The traditional oxygen sensing device  13  comprises an oxygen sensing unit  130  and a voltmeter  131 . The oxygen sensing unit  130  comprises a conductive catalyst layer  132 , a solid oxide electrolyte  133  and a conductive catalyst layer  134 . The solid oxide electrolyte  133  is disposed between the conductive catalyst layer  132  and the conductive catalyst layer  134 . The conductive catalyst layer  132  receives the gas from the turbine  12 . The oxygen concentration of the gas from the turbine  12  is unknown. The conductive catalyst layer  134  receives air from the atmosphere with oxygen concentration of 0.21 atm. A voltage difference would be occurred between the conductive catalyst layer  132  and the conductive catalyst layer  134 , and the voltage difference could be measured by the voltmeter  131 . When the oxygen concentration of the gas from the turbine  12  is less, the voltmeter  131  could sense a larger voltage difference. On the contrary, when the oxygen concentration of the gas from the turbine  12  is more, the voltmeter  131  could sense a smaller voltage difference. Accordingly, the oxygen sensing device  13  generates the control signal A/F to adjust the ratio (A/F) of the air and the fuel transmitted to the internal combustion engine  11 . Therefore, the combustion process in the internal combustion engine  11  could be adjusted. 
         [0006]    However, the traditional oxygen sensing device  13  has only the aforementioned single-function, thus applications of the oxygen sensing device  13  may be limited thereto. 
       SUMMARY OF THE INVENTION 
       [0007]    The object of the instant disclosure is to offer an oxygen sensing device with capability of storing energy and releasing energy for processing chemical reactions, such as catalytic reaction, oxygen sensing, power generation, electrolysis for storing energy and electrolysis for making synthesis gas. 
         [0008]    In order to achieve the aforementioned objects, according to an embodiment of the instant disclosure, an oxygen sensing device is offered. The oxygen sensing device comprises an oxygen sensing unit, a gas storing unit and a control unit. The oxygen sensing unit comprises a first conductive catalyst layer, a second conductive catalyst layer and a solid oxide electrolyte. The solid oxide electrolyte is disposed between the first conductive catalyst layer and the second conductive catalyst layer. The control unit comprises a voltmeter, a power output circuit, a power source and a judgment circuit. The voltmeter senses a voltage generated between the first conductive catalyst layer and the second conductive catalyst layer when the oxygen sensing unit senses the oxygen concentration difference. The power output circuit outputs an electric power, wherein the oxygen sensing unit causes a reaction of the hydrocarbons stored in the gas storing unit and the oxygen for generating the electric power to the power output circuit. The judgment circuit controls conducting status of a power source, the voltmeter, or the power output circuit through at least a switch. The judgment circuit controls the gas storing unit to store the gas generated by the oxygen sensing unit or provide the gas to the gas sensing unit, wherein the electric power is provided to the first conductive catalyst layer of the oxygen sensing unit for processing a catalytic reaction to generate hydrocarbons. The oxygen sensing unit utilizes the electric power of power source of the control unit to generate hydrogen or carbon monoxide. 
         [0009]    In summary, the oxygen sensing device according to an embodiment of the instant disclosure could process catalytic reaction, oxygen sensing, electrical energy generating, electrolysis for storing energy and making synthesis gas (carbon monoxide and hydrogen). Therefore, pollution exhaust could be decreased, pollution exhaust could be used for power generation, the surplus electricity could be used, or the industrial synthesis gas (carbon monoxide and hydrogen) could be made too. 
         [0010]    In order to further the understanding regarding the instant disclosure, the following embodiments are provided along with illustrations to facilitate the disclosure of the instant disclosure. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1A  shows a schematic diagram of a traditional fuel converting mechanism of a car; 
           [0012]      FIG. 1B  shows a schematic diagram of a traditional oxygen sensing device; 
           [0013]      FIG. 2  shows a schematic diagram of an oxygen sensing device according to an embodiment of the instant disclosure; 
           [0014]      FIG. 3A  shows a schematic diagram for an electrochemical catalytic reaction of an oxygen sensing unit according to an embodiment of the instant disclosure; 
           [0015]      FIG. 3B  shows a schematic diagram of the operation for an electrochemical catalytic reaction of an oxygen sensing device according to an embodiment of the instant disclosure; 
           [0016]      FIG. 4  shows a schematic diagram of an oxygen sensing unit processing the oxygen sensing according to an embodiment of the instant disclosure; 
           [0017]      FIG. 5A  shows a schematic diagram of an oxygen sensing unit processing the reaction of hydrocarbons and oxygen according to an embodiment of the instant disclosure; 
           [0018]      FIG. 5B  shows a schematic diagram of a output circuit of an oxygen sensing device outputting electricity according to an embodiment of the instant disclosure; 
           [0019]      FIG. 6  shows a schematic diagram of an oxygen sensing unit generating hydrogen and monoxide according to an embodiment of the instant disclosure; 
           [0020]      FIG. 7A  to  FIG. 7D  shows a cross-sectional diagram of an oxygen sensing unit according to an embodiment of the instant disclosure. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    The aforementioned illustrations and following detailed descriptions are exemplary for the purpose of further explaining the scope of the instant disclosure. Other objectives and advantages related to the instant disclosure will be illustrated in the subsequent descriptions and appended drawings. 
         [0022]    This embodiment offers an oxygen sensing device could process chemical reactions, such as catalytic reaction, oxygen sensing, electrical power generation, electrolysis for storing energy and electrolysis for making synthesis gas. The oxygen sensing device could be installed in a car or a power plant, and the oxygen sensing device can process one of the aforementioned reactions according to usage requirements. 
         [0023]      FIG. 2  shows a schematic diagram of an oxygen sensing device according to an embodiment of the instant disclosure. The oxygen sensing device  2  comprises an oxygen sensing unit  21 , a gas storing unit  22  and a control unit  23 . The oxygen sensing unit  21  comprises a solid oxide electrolyte  212 , a conductive catalyst layer  211  and a conductive catalyst layer  213 . The control unit  23  comprises a power source  24 , a voltmeter  29 , a power output circuit  25 , a judgment circuit  26  and switches  27 ,  28 . The power output circuit  25  comprises a switch  251  and a resistor R. 
         [0024]    The solid oxide electrolyte  212  is disposed between the conductive catalyst layer  211  and the conductive catalyst layer  213 . The gas storing unit  22  is connected to the conductive catalyst layer  211  and the conductive catalyst layer  213  of the oxygen sensing unit  21 . The oxygen sensing unit  21  is electrically coupled the control unit  23 . The power source  24 , the voltmeter  29  and the power output circuit  25  of the control unit  23  are connected in parallel and electrically coupled to the conductive catalyst layer  211  and the conductive catalyst layer  213 . The switch  251  and the resistor R of the power output circuit  25  are connected serially. The switch  27  and the switch  28  are serially connected to the voltmeter  29  and the power source  24  respectively. The judgment circuit  26  is electrically coupled to the switches  251 ,  27 , and  28  and the gas storing unit  22 . 
         [0025]    The solid oxide electrolyte  212  of the oxygen sensing unit  21  may be metal oxides, such as ZrO 2 , CeO 2  . . . etc. The conductive catalyst layer  211 ,  213  may comprise metal catalyst, oxide catalyst or metal oxide catalyst. The metal catalyst may be Platinum (Pt), Rhodium (Rh), or Palladium (Pd). Platinum (Pt) and Rhodium (Rh) are catalyst for converting the oxides of nitrogen (NO X ) to nitrogen (N 2 ) and oxygen (O 2 ). Palladium (Pd) is catalyst for converting the carbon monoxide (CO) to carbon dioxide (CO 2 ). The oxide catalyst may be Lanthanum-Strontium-Cobalt pervoskite, for example, the Lanthanum- Strontium -Manganese oxide (LaSrMnO) may catalyze reaction of oxygen ion (O 2− ) with oxides of nitrogen (NO X ), Methane (CH 4 ), or carbon monoxide (CO). The metal oxide catalyst may be Zirconia (ZrO 2 ) or Cerium oxide (CeO 2 ). The conductive catalyst layer  211 ,  213  may be conductors or carriers with large surface area (e.g. Alumina, Zeolite) coated with aforementioned metal catalyst, oxide catalyst or metal oxide catalyst. 
         [0026]    The gas storing unit  22  receives the exhausted gas (generated by the internal combustion engine) transmitted from the turbine. The gas storing unit  22  is controlled by the judgment circuit  26  for transmitting the gas stored in the gas storing unit  22  to the oxygen sensing unit  21  or storing the gas generated by the oxygen sensing unit  21 . The gas storing unit  22  may comprise at least a two-way valve (not shown in the figure) to make the gas flowing between the gas storing unit  22  and the oxygen sensing unit  21 . Those skilled in the art will readily observe the valve of the gas storing unit  22 , thus there is no need to go into details. 
         [0027]    The power output circuit  25  comprises the switch  251  and the resistor R. The power output circuit  25  has output terminals a, b. Electrical equipment (not shown in the figure) could be connected to the output terminals a, b for obtaining electrical power. The switch  251  is controlled by the judgment circuit  26 . When the switch  251  is conductive, the power output circuit  25  and the electrical equipment could perform a conducting loop. The resistor R of the power output circuit  25  is an output resistance for adjusting the output power. 
         [0028]    The judgment circuit  26  is for controlling the oxygen sensing device  2  to perform functions, and the judgment circuit  26  may be connected to exterior interface (not shown in the figure). A user may manipulate the interface to make commands (or controlling signals) to the judgment circuit  26  of the oxygen sensing device  2 , and the judgment circuit  26  could determine to execute corresponding functions according to the commands (or controlling signals). According to the executed function of the oxygen sensing device  2 , the judgment circuit  26  controls the conducting state of the switches  251 ,  27 , and  28 . The judgment circuit  26  controls the power output circuit  25 , the voltmeter  29 , and the power source  24  through the switches  251 ,  27 , and  28 . The judgment circuit  26  may also controls the gas storing unit  22  to store the gas generated by the oxygen sensing unit  21 , or makes the gas storing unit  22  provide gas to the oxygen sensing unit  21 . In practical applications, the judgment circuit  26  may be accomplished by a micro controller unit (MCU), however the instant disclosure is not restricted thereto. 
         [0029]    Please refer to  FIG. 3A  and  FIG. 3B ,  FIG. 3A  shows a schematic diagram for an electrochemical catalytic reaction of an oxygen sensing unit according to an embodiment of the instant disclosure,  FIG. 3B  shows a schematic diagram of the operation for an electrochemical catalytic reaction of an oxygen sensing device according to an embodiment of the instant disclosure. When the oxygen sensing device  2  processes the electrochemical catalytic reaction, the conductive catalyst layer  211  of the oxygen sensing unit  21  may process catalytic reaction of oxides of nitrogen (NO X ) and carbon monoxide (CO) exhausted from the turbine (not shown in the figure) of the car. The gas exhausted from the turbine may be transmitted to the gas storing unit  22 , then the judgment circuit  26  of the control unit  23  makes the exhausted gas stored in the gas storing unit  22  be transmitted to the conductive catalyst layer  211 . For example, the judgment circuit  26  may open the valve between the conductive catalyst layer  211  and the gas storing unit  22  to make the exhausted gas be transmitted to the conductive catalyst layer  211 . When judgment circuit  26  conducts the switch  28 , the power source  24  could provide electrical power (electrons e − ) to the conductive catalyst layer  211  of the oxygen sensing unit  21  for processing the catalytic reaction to generate hydrocarbons, and the hydrocarbons may be stored to the gas storing unit  22 . For example, when the conductive catalyst layer  211  comprises Platinum (Pt), Rhodium (Rh) and Palladium (Pd), the oxides of nitrogen (NO X ) in the exhausted gas could make a reaction (1) through the catalyst of Platinum (Pt) and Rhodium (Rh), the reaction (1) is described in the following: 2NO X +2e − →O 2− +N 2 . 
         [0030]    In the reaction (1), the oxides of nitrogen (NO X ) is converted to nitrogen (N 2 ). Additionally, the oxygen ions (O 2− ) can be transmitted to the conductive catalyst layer  213  through the solid oxide electrolyte  212 . And, the conductive catalyst layer  213  converts the oxygen ions (O 2− ) into oxygen (O 2 ) and transmits the excess electrons e −  to the power source  24 . On the other hand, the catalyst of Palladium (Pd) makes a reaction (2) of carbon monoxide (CO) of the exhausted gas, the reaction (2) is described in the following: CO+O 2− →CO 2 +2e − . 
         [0031]    The solid oxide electrolyte  212  conducts oxygen ions (O 2− ) needed in the reaction (2), and the electrons (e − ) generated in the reaction (2) may be transmitted to the power source  24  through the conductive catalyst layer  211 . It is worth mentioning that when the switch  28  is conductive, the switch  27  and the switch  251  are non-conductive. 
         [0032]    Please refer to  FIG. 2  and  FIG. 4 ,  FIG. 4  shows a schematic diagram of an oxygen sensing unit processing the oxygen sensing according to an embodiment of the instant disclosure. The judgment circuit  26  of the control unit  23  conducts the switch  27  to make the voltmeter  29  for sensing the voltage difference between the conductive catalyst layer  211  and the conductive catalyst layer  213 . Meanwhile, the switch  28  and the switch  251  are non-conductive. 
         [0033]    The conductive catalyst layer  211  of the oxygen sensing unit  21  receives the exhausted gas from the turbine, the exhausted gas may comprise carbon dioxide (CO 2 ), water (H 2 O), oxides of nitrogen (NO X ), hydrocarbons (HC), carbon monoxide (CO), and oxygen (O 2 ). The manner for sensing oxygen of the oxygen sensing device  2  is the same as to the manner for sensing oxygen of the traditional oxygen sensing device  1  (shown in  FIG. 1B ). It is worth mentioning that the conductive catalyst layer  213  receive the air of atmosphere, the conductive catalyst layer  213  do not receive the gas stored in the gas storing unit  22 . The method of the conductive catalyst layer  211  receiving the exhausted gas generated by the internal combustion engine comprises, the gas storing unit  22  receiving the exhausted gas from the turbine, and the judgment circuit  26  controlling the gas storing unit  22  to transmit the exhausted gas to the conductive catalyst layer  211 . 
         [0034]    Please refer to  FIG. 5A  and  FIG. 5B ,  FIG. 5A  shows a schematic diagram of an oxygen sensing unit processing the reaction of hydrocarbons and oxygen according to an embodiment of the instant disclosure,  FIG. 5B  shows a schematic diagram of a output circuit of an oxygen sensing device outputting electricity according to an embodiment of the instant disclosure. When the oxygen sensing device  2  is used for outputting electricity, hydrocarbons stored in the gas storing unit  22  can make electrochemical catalytic reaction by utilizing the oxygen sensing unit  21  for generating electric current. The electric current may be transmitted to exterior electrical equipment through the power output unit  25 . The conductive catalyst layer  211  of the oxygen sensing unit  21  receives hydrocarbons (HC) stored in the gas storing unit  22  and processes the reaction (3): HC+O 2− →CO 2 +H 2 O+2e − . 
         [0035]    The reaction of hydrocarbons (HC) and oxygen ions (O 2 ) produces carbon dioxide (CO 2 ), water (H 2  O) and electrons (e − ). The oxygen ions (O 2− ) in the solid oxide electrolyte  212  may be replenished through conductive catalyst layer  213  decomposing oxygen of the air into oxygen ions (O 2− ), and the oxygen ions (O 2− ) may be transmitted from the solid oxide electrolyte  212  to the conductive catalyst layer  211 . When the judgment circuit  26  controls the switch  251  to accomplish a conducting loop, the electrons (e − ) generated in the reaction (3) may outcome electric current for power receiving of the electrical equipment connected to the output terminals a, b of the power output circuit  25 . Briefly, the oxygen sensing unit  21  makes the reaction of hydrocarbons (HC) stored in the gas storing unit  22  and oxygen ions for generating electricity to the power output circuit  25 . 
         [0036]    Please refer to  FIG. 2  and  FIG. 6 ,  FIG. 6  shows a schematic diagram of an oxygen sensing unit generating hydrogen and carbon monoxide according to an embodiment of the instant disclosure. When the electrical power of the power source  24  is excess, the electrical power may be stored in the form of hydrogen (H 2 ) generated by the oxygen sensing unit  21 . On the other hand, carbon monoxide (CO) and hydrogen (H 2 ) may be generated from carbon dioxide (CO 2 ) and water (H 2 O) of the exhausted gas from the internal combustion engine by utilizing the oxygen sensing device  2 . The carbon monoxide (CO) and hydrogen (H 2 ) may be upstream material with industrial value, for example, carbon monoxide (CO) and hydrogen (H 2 ) may used to produce chemicals, such as methanol or methane. The judgment circuit  26  of the control unit  23  conducts the switch  28 , makes the switch  27 ,  251  be non-conductive, and makes the exhausted gas stored in the gas storing unit  22  be transmitted to the conductive catalyst layer  211  of the oxygen sensing unit  21 . Because power source  24  supplies electrical power, the conductive catalyst layer  211  makes a reaction (4) of the water (H 2 O) in the exhausted gas and the electrons (e − ) from the power source  24  to produce hydrogen (H 2 ), the reaction (4) is described in the following: H 2 O+2e − →H 2 +O 2− . 
         [0037]    Then, the solid oxide electrolyte  212  transmits the oxygen ions (O 2− ) to conductive catalyst layer  213 . The conductive catalyst layer  213  converts the oxygen ions (O 2− ) into oxygen (O 2 ) and transmits excess electrons (e − ) to the power source  24 . The reaction (4) converts the electricity of the power source  24  into the form of hydrogen (H 2 ) which is green energy replacing fossil fuels. On the other hand, when making carbon monoxide (CO) and hydrogen (H 2 ), the conductive catalyst layer  211  makes a reaction (5) of carbon dioxide (CO 2 ) and water (H 2 O), the reaction (5) is described in the following: CO 2 +H 2 O+4e − →CO+H 2 +2O 2− . Briefly, the oxygen sensing unit  21  may use the electricity of the power source  24  to generate hydrogen (H 2 ) for storing energy or generate carbon monoxide (CO). 
         [0038]      FIG. 7A  to  FIG. 7D  shows a cross-sectional diagram of an oxygen sensing unit according to an embodiment of the instant disclosure. The oxygen sensing unit  21  may be flat-shaped, such as the shape shown in  FIG. 7A  to FIG.  7 C. A thicker one of the solid oxide electrolyte  212 , the conductive catalyst layer  213  or the conductive catalyst layer  211  may utilized to structurally support the oxygen sensing unit  21 . The conductive catalyst layer  213  may surrounds the solid oxide electrolyte  212  and the conductive catalyst layer  211  for covering the solid oxide electrolyte  212  and the conductive catalyst layer  211 . The shape of the conductive catalyst layer  213  may be a cone, a tube, or the shape shown in  FIG. 7D , as long as the solid oxide electrolyte  212  is between the conductive catalyst layer  211  and the conductive catalyst layer  213 . Briefly, the shapes of the conductive catalyst layer  211  and the conductive catalyst layer  213  are not restricted, as long as the solid oxide electrolyte  212  is between the conductive catalyst layer  211  and the conductive catalyst layer  213 . The solid oxide electrolyte  212  may transmits oxygen ions (O 2− ) between the conductive catalyst layer  211  and the conductive catalyst layer  213 . On the other hand, the solid oxide electrolyte  212  may not contact tightly the conductive catalyst layer  211  and the conductive catalyst layer  213 , and an air gap could be existed between the solid oxide electrolyte  212  and the conductive catalyst layer  211  (or conductive catalyst layer  213 ). The air gap may filled with air, thus the aforementioned reactions still could be processed. 
         [0039]    In summary, according to the aforementioned embodiments, the oxygen sensing device may process electrochemical catalytic reactions, oxygen sensing, electrical power generation, electrolysis for storing energy and electrolysis for making carbon monoxide (CO). Therefore, the exhausted gas could be reduced and be used to generate electricity, or syngas (including hydrogen and carbon monoxide) could be made. The user may make the oxygen sensing unit to process required chemical reaction through controlling judgment circuit. 
         [0040]    The descriptions illustrated supra set forth simply the preferred embodiments of the instant disclosure; however, the characteristics of the instant disclosure are by no means restricted thereto. All changes, alternations, or modifications conveniently considered by those skilled in the art are deemed to be encompassed within the scope of the instant disclosure delineated by the following claims.