Porous Protective Layer for Gas Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas sensors face issues with porous protective layers that do not completely block liquid materials, leading to cracks and reduced accuracy in measuring gas concentrations due to thermal shock and deposition of poisonous materials, which affects the response speed and accuracy of gas sensing.
Innovation Solution
A method for manufacturing a porous protective layer for gas sensors using a composition with ceramic powders having a specific degree of deformation and a pore former, which includes sintering to form a durable layer that enhances the gas sensor's ability to accurately measure gas concentrations by preventing external impacts and chemical factors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If a porous protective layer is formed on the gas sensor surface, then the gas sensor can sense the measuring gas, but the porous protective layer does not completely block liquid materials and poisonous materials
Solution Approach 1:
The patent changes the physical and chemical parameters of the protective layer by using specific ceramic materials (alumina, zirconia, silica) with controlled particle sizes (1-10 μm) and porosity (30-70%). The layer thickness is optimized to 10-100 μm to balance gas permeability with protection against liquid and poisonous materials, resolving the contradiction between sensing capability and harmful factor blocking
Solution Approach 2:
The patent employs composite ceramic materials combining multiple ceramic powders (alumina, zirconia, silica) with different properties to create a protective layer that simultaneously provides mechanical strength, chemical resistance to poisonous materials, and controlled porosity for gas sensing. This composite approach enables the layer to block harmful materials while maintaining gas sensing function
2Strength
If a porous protective layer is formed on the gas sensor, then external impacts can be protected, but cracks are generated due to thermal shock from temperature difference
Solution Approach 1:
The patent optimizes the thermal parameters of the protective layer by selecting ceramic materials with thermal expansion coefficients matched to the sensor substrate and controlling the layer thickness (10-100 μm) and porosity (30-70%). These parameter changes reduce thermal stress during temperature transitions, preventing crack formation while maintaining impact resistance
Solution Approach 2:
The patent utilizes the porous structure of the protective layer (30-70% porosity) to mitigate thermal shock effects. The pores act as stress-absorbing features that reduce thermal stress concentration during rapid temperature changes, preventing cracks while maintaining mechanical strength for impact protection
3Reliability
If a porous protective layer is formed on the gas sensor, then protection from external factors is provided, but the response speed of the gas sensor is lowered
Solution Approach 1:
The patent optimizes the porosity parameter of the protective layer to 30-70%, which balances protection capability with gas diffusion efficiency. The controlled pore size (1-10 μm ceramic particles) and layer thickness (10-100 μm) are adjusted to allow rapid gas molecule transport to the sensing elements while maintaining effective protection against liquid and poisonous materials, thus preserving fast response speed
4Strength
If a porous protective layer is formed on the gas sensor, then the gas sensor is protected, but materials separate from the gas sensor and pores collapse
Solution Approach 1:
The patent uses composite ceramic materials (alumina, zirconia, silica) with complementary properties where zirconia provides crack resistance, alumina provides mechanical strength, and silica contributes to pore structure stability. This composite composition prevents pore collapse and material separation while maintaining protective function
Solution Approach 2:
The patent controls the particle size of ceramic powders (1-10 μm) and layer thickness (10-100 μm) to optimize the mechanical interlocking and adhesion between the protective layer and gas sensor substrate. These parameter changes ensure the layer remains firmly attached while maintaining stable pore structure under operational conditions
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution significantly improves the durability and accuracy of gas sensors by preventing external impacts and chemical deposition, ensuring rapid and precise measurement of gas concentrations while maintaining mechanical strength and preventing pore collapse.
Implementation Method 1
a step of sintering the introduced composition for forming a porous protective layer
Implementation Method 2
the porous protective layer for a gas sensor includes ceramic powders having a degree of deformation of 1.5 or more... and is formed by welding at least one region of each particles of the ceramic powder to another particle of the ceramic powder
Data Source
AI summary
Provided is a method of manufacturing a porous protective layer for a gas sensor. The porous protective layer according to one Example of the present invention is manufactured by a method of manufacturing a porous protective layer for a gas sensor including (1) a step of introducing a composition for forming a porous protective layer including a pore former and a ceramic powder, which includes particles having a degree of deformation of 1.5 or more expressed by the following Relational Formula 1 according to the present invention, onto a sensing electrode for a gas sensor, and (2) a step of sintering the introduced composition for forming a porous protective layer.