Knowledge

How Does A Temperature-Programmed System Influence Molybdenum Carbide Formation? Expert Catalyst Synthesis Guide

Learn how temperature-programmed systems control reaction kinetics, phase purity, and physical structure in molybdenum carbide catalyst synthesis.

What Role Does An Industrial-Grade Tube Furnace Play In The Pyrolysis Of Nickel-Modified Molybdenum Carbide Catalysts?

Learn how industrial tube furnaces enable precise in-situ carbonization and phase-specific reduction for high-performance catalyst synthesis.

Why Is A Vacuum Drying Oven Necessary For Processing Reddish-Brown Precipitates? Preserve Your Catalyst Integrity

Learn why vacuum drying ovens are essential for catalyst precursors, preventing oxidation and maintaining loose powder structures at low heat.

How Does The Heating Rate Control Of A Tube Furnace Affect G-C3N4? Master Precise Thermal Polycondensation

Learn how a 10 °C/min heating rate in a tube furnace ensures high crystallinity and structural regularity during g-C3N4 thermal polycondensation.

What Role Does A High-Temperature Tube Furnace Play In The Preparation Of Cellulose-Based Carbon Nanofibers?

Learn how high-temperature tube furnaces enable cellulose carbonization through precise pyrolysis and atmosphere control.

Why Is It Essential To Maintain An Environment Between 80 And 120°C? Optimize Your Plastic Deformation Processing

Learn why 80-120°C is the critical temperature window for plastic deformation to reduce yield strength and prevent brittle cracking.

What Is The Purpose Of Using A Vacuum Oven For La-Cote2 Battery Electrodes? Ensure Purity & Performance

Learn how vacuum ovens optimize La-CoTe2 electrode drying by preventing oxidation and accelerating moisture removal at low temperatures.

Why Is An Atmosphere-Controlled Tube Furnace Used For La-Cote2 Synthesis? Master Your Tellurization Process Today

Learn why atmosphere-controlled tube furnaces are critical for Lanthanum-doped Cobalt Telluride synthesis by preventing oxidation and managing Te sublimation.

How Does A High-Precision Furnace Enhance Eis Testing For Niobium-Doped Titanium Dioxide? Achieve Accurate Material Data

Discover how precise temperature control improves EIS testing by stabilizing carrier mobility and ensuring accurate model fitting for doped oxides.

How Does A High-Temperature Muffle Furnace Facilitate The Dual Heat Treatment Of Ti0.96Nb0.04O2? Master Conductivity

Learn how high-temp muffle furnaces use air sintering and argon annealing to transform niobium-doped titanium dioxide into a conductive material.

Why Are Precision Molds And Laboratory Presses Critical For Niobium-Doped Tio2 Ceramics? Achieve 94% Theoretical Density

Learn how precision molds and laboratory presses eliminate density gradients and pores in ceramic green bodies for superior sintering results.

What Role Does Thermal Stability Play In Catalyst Evaluation? Ensure Durability After High-Temp Synthesis

Learn why thermal stability is the ultimate stress test for catalysts, validating morphology retention and preventing sintering after reaction.

How Does The Dispersion Of Ruthenium Precursors On Alumina Carriers Affect Thermal Processing In A Lab Furnace?

Learn how Ru-Macho precursor dispersion on alumina impacts thermal processing outcomes, from single atoms to bulk material formation.

Why Is An Atmosphere Controlled Furnace Required For Ru-3 Nanoparticle Synthesis? Master Precision Catalyst Design

Learn how precise H2/Ar atmospheres and 300°C thermal control enable the synthesis of 2.9 nm Ru-3 nanoparticle catalysts with high stability.

How Does A Muffle Furnace Facilitate The Formation Of Ru-2 Cluster Catalysts? Precision For Ruthenium Calcination

Learn how precise 200°C muffle furnace calcination enables controlled oxidation and stable Ru-Al2O3 interactions for superior Ru-2 catalysts.

What Is The Importance Of The Nitrogen Displacement Step In A Tube Furnace? Secure High-Performance Ru-1 Catalysts

Learn why nitrogen displacement is critical for Ru-1 catalyst synthesis, preventing oxidation and ensuring precise atomic dispersion in lab settings.

What Function Does A Water-Cooling System Serve In Muffle Furnaces? Stability & Precision Secrets Revealed

Learn how water-cooling systems act as thermal stabilizers in muffle furnaces, ensuring structural integrity and ultra-precise heat control.

Why Does The Edge Of A Workpiece Reach Higher Temperatures Than Its Center? Master Thermal Uniformity In Sintering

Understand the physics of thermal gradients in sintering high-entropy alloys and how radiant exposure and conduction lag cause edge overheating.

How Does The Position Of Gas Inlets In A Muffle Furnace Affect The Temperature Distribution? Master Thermal Uniformity

Learn how gas inlet positioning creates temperature gradients in high-entropy alloys and discover strategies to optimize thermal distribution.

What Is The Significance Of Thermal Radiation In Muffle Furnace Sintering? Master Heat Transfer For Precision

Learn why thermal radiation dominates high-temperature sintering and how to manage emissivity and view factors for uniform heat treatment results.

Why Is Heating Tube Spacing Critical In Muffle Furnace Design? Master Thermal Uniformity For Superior Processing

Learn how optimizing heating tube spacing in muffle furnaces ensures thermal uniformity, prevents hot spots, and improves material quality.

How Does The Use Of Gaskets Or Shims To Adjust Workpiece Height Affect The Sintering Process In A Muffle Furnace?

Learn how elevating workpieces with gaskets or shims improves sintering uniformity and heat retention by reducing conductive heat loss to the floor.

What Is The Primary Role Of High-Precision Muffle Furnaces In The Sintering Process Of High-Entropy Alloys?

Learn how high-precision muffle furnaces ensure thermal uniformity to prevent defects and control phase evolution in high-entropy alloys.

What Are The Technical Advantages Of Using A Vacuum Magnetic Levitation Induction Melting Furnace For Heas?

Discover how vacuum magnetic levitation ensures zero contamination and perfect homogeneity for high-purity high-entropy alloy production.

What Is The Purpose Of Using A High-Temperature Muffle Furnace For Nife2O4 Catalyst Precursors? Pure Spinel Formation

Learn how high-temperature muffle furnaces enable calcination, impurity removal, and spinel crystallization for high-performance NiFe2O4 catalysts.

Why Is Controlling The Residence Time Within A Tube Furnace Critical For The Synthesis Of Amorphous Nife2O4 Catalysts?

Learn how controlling residence time in tube furnaces prevents crystallization and preserves active O-H bonds for superior NiFe2O4 catalysts.

What Is The Primary Function Of A High-Temperature Tube Furnace In Aerosol-Assisted Spray Pyrolysis? | Kintek

Learn how tube furnaces drive rapid conversion and kinetic trapping to produce amorphous NiFe2O4 through precise thermal control.

Why Is An Industrial Calcination Furnace Required To Process Carbon-Supported Nickel Catalysts At 600°C In Nitrogen?

Learn why 600°C and a nitrogen atmosphere are essential for decomposing nitrate precursors while protecting carbon-supported nickel catalysts.

What Is The Purpose Of Using A Laboratory Blast Drying Oven At 107°C For 17 Hours For Reforming Catalysts?

Learn why 107°C blast drying for 17 hours is critical for reforming catalyst preparation, ensuring metal dispersion and preventing agglomeration.

How Is A Muffle Furnace Applied In The Active Sulfur Coating Process? Achieve 155 °C Precision For Catalyst Composites

Learn how muffle furnaces enable sulfur infiltration into catalyst micropores at 155 °C to create stable, high-performance battery composites.

What Is The Purpose Of Performing Heat Treatment In A Nitrogen Atmosphere For Zns/Ceo2? Optimize Your Synthesis Process

Learn how nitrogen atmospheres in tube furnaces enable ZnS/CeO2 heterojunction formation, nitrogen-doping of CNTs, and improved conductivity.

What Is The Function Of A Laboratory Vacuum Drying Oven In Catalyst And Electrode Treatment? Ensure Material Integrity

Learn how laboratory vacuum drying ovens preserve catalyst precursors and electrode sheets by removing solvents at low temperatures under vacuum.

How Does The Use Of A Stainless Steel High-Pressure Autoclave Affect Zns/Ceo2@Cnt Formation? Optimize Catalyst Growth

Learn how high-pressure autoclaves regulate crystal growth and porous structures on CNT networks to maximize catalyst surface area.

What Role Does A Muffle Furnace Play In Zno-Doped Cuo Synthesis? Master Precision Nanocomposite Production

Learn how muffle furnaces drive combustion and calcination to create high-purity ZnO-doped CuO nanocomposites with precise 25-31 nm grain sizes.

Why Is A Silica Crucible Selected As The Reaction Vessel? Ensure Stability And Purity In High-Temp Synthesis

Learn why silica crucibles are essential for combustion synthesis, offering unmatched thermal shock resistance and chemical purity for nanocomposites.

Why Is The Purity Of Oxide Precursors Critical For Zno-Doped Cuo? Ensure High Photocatalytic Performance

Learn why 99.99% purity in copper and zinc nitrate precursors is vital for precise doping, bandgap control, and photocatalytic efficiency.

What Is The Role Of Industrial Thermometers In Monitoring Thermal Stress? Ensure Safety Via High-Precision Data

Learn why high-precision thermometers are vital for calculating thermal stress in pressure vessels and preventing dangerous measurement noise errors.

Why Is Thermal Insulation Applied To Cylindrical Components In Thermal Stress Tests? Enhance Calculation Precision

Learn why insulation is used in thermal stress validation to enforce adiabatic boundaries and enable accurate one-dimensional heat analysis.

What Specific Information Does Sem Provide For Lfp Synthesis? Master Battery-Grade Quality Control

Learn how SEM evaluates LFP crystal quality, morphology, and agglomeration to optimize high-temperature furnace sintering programs.

Why Is X-Ray Diffraction (Xrd) Required For Lithium Iron Phosphate Synthesis? Ensuring Phase Purity & Structure

Learn why XRD is essential for characterizing synthesized lithium iron phosphate, from validating crystal structures to optimizing furnace settings.

How Does The Placement Of Materials Within An Atmospheric Tube Furnace Affect The Yield And Purity Of Lifepo4?

Optimize LiFePO4 synthesis by mastering furnace placement. Learn how thermal zones and gas flow impact yield and purity in tube furnaces.

What Are The Advantages Of Ascorbic Acid Over Glucose In Lfp Synthesis? Achieve Superior Purity And Crystallinity

Learn why ascorbic acid outperforms glucose in LiFePO4 synthesis, offering superior crystallinity, fewer impurities, and better reaction kinetics.

Why Is A Nitrogen Atmosphere Essential In A Tube Furnace For Lifepo4 Synthesis? Prevent Oxidation & Ensure Purity

Learn why nitrogen is critical in tube furnaces to prevent Fe2+ oxidation and ensure stoichiometric purity during LiFePO4 synthesis at 700°C.

What Role Does Physical Homogenization Via Planetary Ball Milling Play In Lfp Precursors? Maximize Your Battery Quality

Learn how planetary ball milling optimizes LFP quality by increasing contact area, shortening diffusion paths, and ensuring high phase purity.

Why Is A Vacuum Freeze Dryer Used For Vivianite? Optimize Your Lfp Synthesis With Superior Precursor Integrity

Learn why vacuum freeze drying is essential for processing Vivianite precursors to ensure high porosity and purity for lithium iron phosphate production.

Why Is A Commercial High-Temperature Furnace Required For Tl Material Pretreatment? Ensure Accurate Dosimetry

Learn why precise commercial furnaces are essential for TL material pretreatment, from eliminating shallow traps to stabilizing energy structures.

Why Is A Heating System With Closed-Loop Feedback Essential For Tl Analysis? Precision Tips For High-Accuracy Kinetics

Learn why closed-loop feedback is critical for Thermoluminescence (TL) analysis to ensure <1°C precision and accurate kinetic data resolution.

Why Is A Vacuum Drying Oven Necessary For Activated Carbon? Ensure Accurate Bet And Pore Size Analysis

Learn why vacuum drying is essential for activated carbon degassing to ensure accurate BET surface area and pore size distribution results.

What Are The Essential Functional Requirements For A Tube Furnace Used In The Biomass Activated Carbon Activation Process?

Discover the critical functional requirements for biomass activation, including 1050°C control, inert gas isolation, and programmable profiles.

Why Is A Tube Furnace Essential For The Reduction Treatment Of Y-Nimo/Moo2-X? Master Precision Synthesis

Learn why tube furnaces are vital for Y-NiMo/MoO2-x electrocatalysts, enabling oxygen vacancies and phase transformations via atmosphere control.

What Is The Purpose Of Annealing Prepared Thin Films In An Argon Environment? Optimize Structure & Prevent Oxidation

Learn how argon annealing in tube furnaces transforms amorphous thin films into stable polycrystalline structures while preventing chemical degradation.

What Is The Mechanism Of The Drive-In Process In A Tube Furnace? Master Dopant Redistribution With Nitrogen Shielding

Learn how the drive-in process in a tube furnace redistributes dopants using nitrogen to achieve precise Gaussian profiles without oxidation.

What Are The Specific Functions Of Nitrogen And Oxygen Flow Within A Tube Furnace? Optimize Your Diffusion Process

Understand the roles of nitrogen as a protective carrier and oxygen as a reactive agent in forming PSG layers during furnace diffusion.

How Does A Laboratory Tube Diffusion Furnace Facilitate Pre-Deposition? Precision Doping For Silicon Wafer Processing

Learn how tube diffusion furnaces ensure precise silicon wafer pre-deposition through thermal stability and dopant solubility control.

Why Is A Multi-Stage Thermocouple Measurement System Necessary? Validate Composite Fuel Combustion Performance

Learn why multi-stage thermocouple systems are critical for mapping temperature gradients and validating composite fuel stability and efficiency.

What Is The Function Of A Fast-Response Photoelectric Sensor System? Precision Ignition Timing In Tube Furnaces

Learn how fast-response photoelectric sensors measure fuel ignition delay with millisecond precision in high-temperature tube furnace experiments.

How Is A Vertical Tube Furnace Used For Fuel Dust Ignition Studies? Model Industrial Combustion With Precision

Learn how Vertical Tube Furnaces simulate industrial boiler environments to measure ignition delay and minimum ignition temperature of fuel dust.

What Are The Advantages Of Using Open Corundum Crucibles For Thermal Analysis? Accurate Biomass & Coal Data

Learn why open corundum crucibles are essential for biomass and coal thermal analysis, offering chemical inertness and high thermal conductivity.

What Are The Primary Process Objectives Of Using An Infrared Belt Furnace? Optimize Topcon Solar Cell Metallization

Learn how infrared belt furnaces optimize TOPCon solar cells by decomposing organics, melting glass frit, and preparing electrodes for LECO.

Why Is It Necessary To Use An Annealing Furnace At 350°C For Three Hours? Ensuring Glass Stability And Clarity

Learn why a 350°C annealing cycle is essential for shielding glass to prevent cracks, relieve internal stress, and ensure optical transparency.

How Does A High-Temperature Electric Furnace Contribute To The Melting Process Of Radiation Shielding Glass?

Learn how high-temperature electric furnaces stabilize a 1000°C environment to control viscosity and ensure uniform radiation shielding glass.

What Is The Primary Function Of An Alumina Crucible In Preparing B2O3–Zno–Bao Shielding Glass? Process Secrets Revealed

Learn why alumina crucibles are vital for B2O3–ZnO–BaO glass preparation, ensuring thermal stability and melt purity at 1000°C.

What Role Does A Single-Zone Tube Furnace Play In Synthesizing Znps3? Master The Thermal Profile For Layered Materials

Discover how single-zone tube furnaces facilitate ZnPS3 synthesis through precise heating profiles, 750°C stability, and controlled cooling.

Why Is Vacuum Quartz Tube Sealing Technology Required In The Synthesis Of Znps3 Crystals? Ensuring Chemical Purity

Learn why vacuum quartz tube sealing is essential for ZnPS3 synthesis, from preventing oxidation to enabling chemical vapor transport (CVT).

How Does Sodium Metal Function As A Flux? Enhancing Sr-Ge-N Synthesis With Liquid-Phase Dynamics

Learn how sodium metal acts as a liquid-phase flux to lower reaction temperatures and grow high-quality strontium germanium nitride crystals.

What Role Do Niobium Ampoules Play In Synthesis? Secure High-Temp Protection For Sensitive Germanium Compounds

Learn how Niobium ampoules provide hermetic isolation and chemical inertness for synthesizing strontium germanium nitride oxides up to 720 °C.

Why Is A Tube Furnace With Precise Temperature Control Critical For The Preparation Of Palladium Borosulfates?

Master Palladium Borosulfate synthesis with precise tube furnace control. Learn why 90-hour cooling cycles and PID accuracy are vital for success.

How Are Industrial-Grade High-Temperature Muffle Furnaces Utilized In Experimental Archaeology? Unlock Ancient Tech

Discover how muffle furnaces simulate ancient ceramic distillation, verifying thermal stability and firing curves in experimental archaeology.

What Role Do Industrial Tube Furnaces Play In The Oxidation Of Nicral Alloys? Precise Stability For Reliable Data

Learn how industrial tube furnaces provide stable thermal regulation and oxygen partial pressure for NiCrAl alloy oxidation experiments.

What Is The Function Of A Tube Furnace During The Hydrogen Reduction Phase? Optimize Catalyst Microstructures

Discover how tube furnaces provide precise thermal and gas control for high-performance catalyst synthesis and metallic nanoparticle formation.

Why Is A High-Precision High-Temperature Furnace Required For Chemical Activation? Ensure Superior Carbon Quality

Learn why precise thermal control is critical for activated carbon production, from etching pore structures to managing atmosphere and consistency.

What Process Environment Does A Tube Furnace Provide For Peanut Shell Carbonization? Achieve High-Quality Porosity

Learn how tube furnaces provide inert, oxygen-free environments and precise temperature control for optimal biomass carbonization.

What Is The Technical Value Of Using A Narrowband Infrared Pyrometer? Expert Precision For High-Temp Measurement

Discover why narrowband pyrometers outperform broadband detectors through emissivity stability and the ability to measure targets through barriers.

Why Is A Quartz Tube Selected As The Sample Container For Emissivity Measurement? Precision Microwave Heating Benefits

Discover why quartz tubes are essential for microwave emissivity experiments, offering low dielectric loss and dual-temperature monitoring.

What Are The Core Process Advantages Of Using A Microwave Reactor? Maximize Speed & Efficiency In Lab Characterization

Unlock the benefits of microwave reactors: volumetric heating, rapid thermal cycles, and oxidation control without expensive vacuum systems.

Why Are Precision Hydrothermal Reactors Necessary For Nut Shell Modification? Unlock Biomass Energy Potential

Learn how precision hydrothermal reactors optimize nut shell modification through controlled thermochemical environments and lignin removal.

What Role Does A Laboratory Muffle Furnace Play In The Ash Analysis Of Plant Samples? Achieve Clean Mineral Isolation

Learn how muffle furnaces use dry ashing to isolate inorganic minerals from plant samples by removing organic matter through thermal decomposition.

What Is The Primary Function Of A Forced Convection Oven In Plant Sample Preparation? Ensure Accurate Data Every Time

Learn how forced convection ovens stabilize plant samples, halt biological activity, and ensure precise dry weight baseline for analytical accuracy.

Why Is A High-Precision Gas Mass Flow Control System Necessary For Ga2O3 Growth? Achieve Defect-Free Thin Films

Learn how precise O2/Ar gas flow control optimizes plasma density and minimizes oxygen vacancies in Gallium Oxide (Ga2O3) thin film growth.

What Are The Functions Of A High Vacuum Mechanical Pump In Ga2O3 Peto? Ensure Purity In Film Preparation

Learn the critical roles of mechanical pumps in Gallium Oxide PETO: from pre-oxidation evacuation to maintaining plasma stability and purity.

How Does A Radio Frequency (Rf) Plasma-Enhanced Horizontal Tube Furnace Contribute To The Synthesis Of Ga2O3 Thin Films?

Learn how RF plasma-enhanced furnaces use atomic oxygen radicals to accelerate Ga2O3 thin film synthesis with superior efficiency and control.

How Does A High-Temperature Tube Furnace Facilitate Coal Combustion Simulation? Mastering Industrial R&D

Learn how tube furnaces replicate industrial boiler conditions, regulate oxidation, and evaluate SO2/NOx removal in lab combustion research.

How Do Box High-Temperature Furnaces And Thermocouples Ensure Hp40Nb Alloy Test Precision? Master Thermal Stability

Learn how combining box resistance furnaces with Pt-Pt13%Rh thermocouples ensures precise thermal control for HP40Nb alloy exposure testing.

Why Is It Necessary To Perform Annealing In A Tube Furnace With A Nitrogen Atmosphere For Vo2@Alf3 Core-Shell Powder?

Learn why a nitrogen atmosphere and precise tube furnace annealing are vital to prevent VO2 oxidation and stabilize AlF3 core-shell structures.

What Are The Advantages Of Using A Vacuum Oven For Drying Vo2@Alf3? Protect Your Sensitive Core-Shell Nanostructures

Discover why vacuum drying is essential for VO2@AlF3 to prevent thermal oxidation, ensure structural integrity, and achieve deep pore extraction.

What Is The Objective Of Gc-Ms Analysis On Bio-Oil? Unlock Chemical Value And Industrial Utility

Learn how GC-MS analysis identifies high-value compounds like phenols in bio-oil to determine its use as a feedstock or fuel.

How Does An Automatic Temperature Control System Affect Bio-Char? Engineer Precise Energy Density & Pore Structure

Learn how automatic temperature control systems optimize bio-char development through precise heating rates and real-time monitoring.

Why Is A High-Purity Argon Supply System And A Flow Meter Integrated Into A Tube Furnace? Optimize Pyrolysis Quality

Learn how argon systems and flow meters prevent oxidation and secondary cracking in tube furnace pyrolysis for superior material results.

What Are The Technical Advantages Of Using A Horizontal Tube Furnace For The Slow Pyrolysis Of Cotton Stalks?

Discover how horizontal tube furnaces optimize cotton stalk pyrolysis through precise heating, uniform thermal fields, and oxygen-free environments.

What Is The Primary Function Of A Laboratory Drying Oven In Cotton Stalk Pyrolysis? Ensure Data Integrity

Learn why pre-treating cotton stalks at 105°C in a laboratory drying oven is essential for accurate TGA and pyrolysis product consistency.

How Does A Lab Furnace Use Eutectic Points For Boron Carbide Sintering? Achieve High-Density Ceramics At Lower Heat

Learn how high-precision furnaces leverage eutectic point principles and Y2O3-Al2O3 additives to densify Boron Carbide through liquid phase sintering.

How Does Atmosphere Control In A Laboratory Tube Furnace Affect Boron Carbide Powders? Optimize Your Surface Chemistry

Learn how atmosphere control at 500°C determines Boron Oxide formation and sintering activity for Boron Carbide powders in tube furnaces.

Why Is An Industrial Drying Oven Necessary For Boron Carbide Mixed Slurries? Ensure Coating Integrity & Precision

Learn why industrial drying ovens are vital for processing Boron Carbide slurries to prevent boiling and preserve delicate additive layers.

What Is The Primary Function Of A Vacuum Sealed Tube Furnace In Black Phosphorus Synthesis? Master Phase Transformation

Learn how vacuum sealed tube furnaces enable black phosphorus synthesis through precision thermal control and programmed step-cooling.

What Is The Purpose Of Using A High-Temperature Tube Furnace With A Steam Generator For Loca Simulation?

Learn how tube furnaces and steam generators simulate LOCA environments to test Accident Tolerant Fuel (ATF) coatings at 1200°C.

How Do The Rotational And Orbital Movements Of The Sample Stage Contribute To The Uniformity Of Coatings On Zircaloy?

Learn how dual-motion sample stages eliminate shadowing and ensure uniform film thickness and chemical composition on complex Zircaloy substrates.

What Are The Roles Of The Vacuum Pumping System And Argon Gas Input In Tin/Cr Deposition? Ensure Peak Coating Purity

Learn how vacuum systems and argon input control plasma stability and eliminate impurities to create single-phase TiN and Cr coatings.

What Is The Technical Value Of Using A Vacuum Drying Oven? Master Platinum Catalyst Precision And Activity

Learn how vacuum drying prevents platinum agglomeration, preserves active sites, and protects catalyst pore structures at low temperatures.

Why Is A High-Precision Tube Furnace Required For Ptcln/Fe-N-C Catalysts? Ensure Sub-Nanometer Precision

Learn how high-precision tube furnaces provide the atmosphere control and thermal stability needed to prevent coarsening in PtCln/Fe-N-C catalysts.

What Is The Role Of Mortar Grinding Combined With Heat Gun Processing In Catalyst Synthesis? Achieving Ptcln Dispersion

Learn how mortar grinding and heat gun processing ensure uniform PtCln dispersion on Fe-N-C supports by preventing precursor aggregation.