Simple Thermal Decomposition Research Articles

Efficacy of nickel doped graphitic carbon nitride as energy storage material

Abstract The current article reports the synthesis of graphitic carbon nitride (GCN), through simple thermal decomposition of urea at a moderate temperature of 550 oC and doping of as-developed material with transition element like nickel. The proper phase formation of the sample was confirmed by X-ray diffraction whereas electron microscopic images analyzed the sample morphologies. The successful doping was verified by X-ray photoelectron spectroscopy whereas thermogravimetric study predicted the stability of the material under elevated temperature. Fourier transformed infrared spectroscopy showed that after Ni doping there is a substantial change in the vibrational energy level of the sample. UV-Vis reflectance spectra confirmed the reduction of optical bandgap after metal doping. 
The samples show promises towards supercapacitor application. Cyclic voltametric study shows that after metal doping the value of specific capacitance became 162 Fg-1 at scan rate 5 mV/s and when the same was calculated from galvanostatic charging-discharging characteristics the values came even higher. The energy and power density of both the samples was calculated and all these when compared with different reported results, confirmed the performance of Ni doped GCN is comparable and sometimes even far better along with the advantages of the easy, large scale and high yield synthesis approach.

Strongly Interacting Nanoferrites for Magnetic Particle Imaging and Spatially Resolved Thermometry.

High-crystal-quality nanoferrites with short surface ligands (oleic acid) were recently shown to exhibit enhanced sensitivity and spatial resolution, likely due to chain formation (uniaxial assemblies of particles) for magnetic particle imaging (MPI). Here, we develop a simple one-pot thermal decomposition approach to produce ferrite (iron oxide) magnetic nano-objects (MNOs) that strongly interact magnetically and have good synthetic reproducibility. The ferrite MNOs were physically characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and dynamic light scattering. The MNOs were magnetically characterized by magnetometry and magnetic particle spectroscopy (MPS) to study their interactions, dynamics, and suitability for spatially resolved magnetic thermometry. The MNOs were synthesized in a range of sizes between 12 nm and 27 nm, showing that MNOs below a minimum size do not exhibit dynamic interactions/significant increased response and that a larger field is required for chain formation as size increases. In addition to size effects, we explore the role of ligand length, environment (liquid vs solid), and concentration on the proposed chain formation. The experimental results were then correlated to micromagnetic simulations to gain further insight into the formation of chains. Compared to some existing MPI tracers, our ferrite MNOs exhibit enhanced signal (up to about 37×) and spatial resolution (up to about 9×) under certain limited (ferrite-MNO optimal) field and frequency conditions used. MPS as a function of temperature and drive field amplitude was performed, showing promise for spatially resolved thermometry. These results confirm the importance of tuning the frequency and amplitude of the drive field for optimal imaging/thermal performance.

Agarose derived carbon based nanocomposite for hydrogen storage at near-ambient conditions

Nanocomposites of high surface area adsorption materials and nanosized transition metals have emerged as a promising strategy for hydrogen storage applications. However, their potential use in both transport and stationary applications depends on reaching the ultimate storage capacity at near-ambient conditions along with scalable synthesis protocols. Herein, a direct and simple thermal decomposition technique is reported to synthesize carbon-based nanocomposite, where nickel nanoparticles are dispersed in a porous carbon matrix. It is also demonstrated that the storage capacity can be enhanced at near-ambient conditions by effectively engineering the microstructure and synergistically combining the ‘physisorption’ and ‘spillover’ mechanism. The structure, composition and morphology of the samples were investigated using X-ray diffraction, energy dispersive spectroscopy, transmission and scanning electron microscopy. Sorption-desorption isotherms were obtained to study the hydrogen storage capacity at a moderate H2 pressure of 20 bar. The nanocomposite showed a promising storage capacity of 0.73 wt% at 298 K with reversible cyclability. It is shown that the uniform dispersion of catalytic nanoparticles leads to an increase in the spillover efficiency, which further helps in the enhancement of hydrogen storage capacity by a factor of 6.5 over pure carbon.

Modulated upconversion luminescence of water-dispersed NaErF4@NaYF4 nanoparticles by introducing Tm3+/Ho3+ as energy capture centers under multi-wavelength NIR excitation

Water-dispersed red upconversion nanoparticles (UCNPs) have great application prospects in the biomedical field. Thus, a series of Er3+-based upconversion nanoparticles (Er-UCNPs) with excellent red upconversion luminescence under three-wavelength NIR excitation (808/980/1550 nm) were prepared by a simple thermal decomposition method, and then further functionalized by PAA to achieve good water dispersibility. Compared with NaErF4 bare core, the emission intensity of Er-UCNPs samples doping of 0.5%Tm3+ and 0.5%Ho3+ as energy capture centers was significantly enhanced, and further improved after coating with NaYF4 inert shell. Meanwhile, among all Er-UCNPs@NaYF4 samples, NaErF4@NaYF4 exhibited the highest emission intensity and longest luminescence lifetime due to the efficient suppression of luminescence quenching effect, while NaErF4:0.5%Tm3+@NaYF4 showed highest red luminescence purity owing to the energy transfer process between Tm3+(3H5) and Er3+(4I13/2). The hydrophilic Er-UCNPs@NaYF4@PAA samples still maintained good red luminescence under multi-wavelength excitation. The luminescence enhancement mechanism in Er-UCNPs@NaYF4 was discussed in detail based on spectral characteristics. The as-prepared water-dispersed Er-UCNPs@NaYF4@PAA with bright red luminescence under multi-wavelength NIR excitation will have potential applications in targeted therapy and deep tissue imaging.

The crucial role of casein on crystal structure, size, morphology, and magnetic properties of carbon supported Ni nanoparticles

Carbon supported nonprecious metal nanoparticles have gained significant attention for their low cost and excellent properties. However, immobilizing them with good dispersion on carbon supports is still a great challenge. Herein, we report a simple and low cost thermal decomposition method to prepare a high quality carbon supported nickel nanoparticles in presence of casein as carbon source. By optimizing the concentration of carbon source, engineered the particle size from 50 nm to 17 nm and morphology from pyramid to spherical. Further, the impacts of morphology and particle size on the magnetic properties of these nanoparticles are studied. Moreover, thermally stable, biocompatible, low cost with unique magnetic properties makes these materials as potential candidate for various applications including chemisorbers, sensor, and electrochemical uses.

An electrochemical sensing potential of cobalt oxide nanoparticles towards citric acid integrated with computational approach in food and biological media

Although citric acid (CA) has antioxidant, antibacterial, and acidulating properties, chronic ingestion of CA can cause urolithiasis, hypocalcemia, and duodenal cancer, emphasizing the need for early detection. There are very few documented electrochemical-based sensing methods for CA detection due to the challenging behavior of electrode fouling caused by reactive oxidation products. In this study, a novel, non-enzymatic, and economical electrochemical sensor based on cobalt oxide nanoparticles (CoOxNPs) is successfully reported for detection CA. The CoOxNPs were synthesized through a simple thermal decomposition method and characterized by SEM, FT-IR, EDX, and XRD techniques. The proposed sensing platform was optimized by various parameters, including pH (7.0), time (15 min), and concentration of nanoparticles (100 mM) etc. In a linear range of 0.05–2500 μM, a low detection limit (LOD) of 0.13 μM was achieved. Theoretical calculations (ΔRT), confirmed hydrogen bonding and electrostatic interactions between CoOxNPs and CA. The detection method exhibited high selectivity in real media like food and biological samples, with good recovery values when compared favorably to the HPLC method. To facilitate effective on-site investigation, such a sensing platform can be assembled into a portable device.

Highly stable TiO2/g-C3N4 composite electrodes for quasi-solid-state supercapacitor applications

Supercapacitor research focuses on cheap, long-lasting electrode materials. As a semiconductor, titanium dioxide (TiO2) is cheap and chemically stable, making it a promising electrode material for supercapacitors. The goal is to improve carbon-based composites by hybridizing conductive materials. The graphitic carbon nitride (g-C3N4) is a stable and common allotrope of C3N4. Its optical, electrical, and structural properties make it a good hybrid system for supercapacitors. With a simple, affordable, and successful thermal decomposition method, we synthesized a TiO2/g-C3N4 composite material. Supercapacitors have 20.6 F g−1 specific capacitance, 63 Wh kg−1 energy density, and 92 % Coulombic efficiency. The TiO2/g-C3N4 composite showed highly stable electrochemical performance even after 10,000 charge–discharge cycles.

Cu nanoparticles grafting on the surface of ZnO nanostructures to boost the porosity and surface area for effective removal of manganese ions from aqueous solutions

Designing highly adsorptive materials for wastewater treatment via facile approaches is still challenging. To boost the recovery of heavy metals from wastewater, surface and structure modification are considered a successful route. Herein, we report the design of ZnO nanoparticles by a simple thermal decomposition method followed by grafting Cu nanoparticles (Cu NPs) over the ZnO surface. Cu/ZnO was prepared with different Cu ratios, 0.01 and 1%. It was found that incorporating Cu into ZnO improved the porosity and surface area of ZnO. The adsorption ability of Cu/ZnO compared with bare ZnO was studied towards removing manganese ions from wastewater. The effects of several parameters, such as pH, temperature, contact time, and initial ion concentrations, were studied. The maximum removal of manganese was found at pH 2, 20 °C after 60 min in the presence of 1 g/L adsorbent. The role of Cu grafted on the surface of ZnO was discussed. The rates of adsorption were found to follow the pseudo-second-order model. The results showed better fitting to Freundlich isotherm. The thermodynamic study revealed that the sorption process is spontaneous, exothermic, and favorable at low temperatures. The free energy (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) changes were calculated to predict the nature of adsorption.Graphical

Investigation of Visible and UV Light‐Induced Photocatalysis Properties of Oleic Acid‐Ligated Cobalt‐Mixed Magnesium Ferrite Nanoparticles for Photodegradation of Cationic and Anionic Dyes

Owing to numerous potential applications in multiple fields, the study of nanosized magnetic spinel ferrites has been gaining significance. Synthesis and characterization of high‐quality magnetic nanocrystals with narrow size distribution, enhanced magnetic saturation, and outstanding properties for bioenvironmental applications are presented in the current study. Nanoparticles of oleic acid‐ligated Co0.5‐mixed Mg0.5Fe2O4 were prepared by a simple thermal decomposition method. The effect of cobalt (Co2+) content on the structural, optical, magnetic, and thermal properties of magnesium ferrite was assessed by powder X‐ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT‐IR), and vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). High‐resolution transmission electron microscopy (HR‐TEM) and energy dispersive X‐ray (EDX) spectroscopy were used to determine morphology and composition, respectively. Nanoparticles produced are highly crystalline and homogeneous, having an average size of 10 nm, with large saturation magnetization (61 emu/g) and high magnetic moment. Photocatalytic properties of prepared nanocrystals were studied by degradation of anionic Orange II and cationic methylene blue (MB) dyes under UV and visible light radiations for different time intervals. The anionic Orange II dye exhibited higher degradation, up to 97.2% and 92.2%, within a 90‐minute time period of ultraviolet and visible light irradiation, respectively. The cationic MB dye also displayed significant degradation, up to 91.9% and 93.8%, within 300 min under UV and visible light sources, respectively. The synthesized OA‐ligated nanoparticles degrade cationic and anionic dyes more effectively than previously reported in the literature and, thus, can be prime candidates for effective photo catalytic dye degradation and waste water cleaning applications, through the harvesting of ambient solar energy.

Fe30Co70/Co/CoxFe3−xO4-δ nanocomposite with multiple magnetic exchange resonance mechanisms and large magnetic loss available for microwave absorption application

Soft magnetic alloys are widely studied and reported as a type of important microwave absorption (MA) materials, while their magnetic losses are limited. In this paper, a multiphase composite strategy of the soft magnetic alloys, hard magnetic metals, and hard magnetic ferrites is adopted for increasing the magnetic loss. Then, three-phase Fe50Co50/CoxFe3−xO4-δ/γ-Fe2O3 (FC31), three-phase Fe30Co70/Co/CoxFe3−xO4-δ (FC22), and three-phase CoxFe3−xO4-δ/Co3O4/Co (FC13) nano-composites are prepared by a simple thermal decomposition process of FeC2O4 and CoC2O4 in vacuum. The crystal structure, surface composition, vibration of chemical bonds, morphology, micro-structure, and static magnetism are characterized by XRD, XPS, FTIR, Raman, SEM, TEM, and SQUID, respectively. The electromagnetic (EM) parameters are measured in 2–18 GHz by a vector network analyzer. Based on the measured EM parameters, the calculated magnetic loss tangents (tanδm) are over 0.5 in a wide frequency band of 8–18 GHz for the FC22/paraffin absorber, showing that the tanδm can be increased dramatically through the multiphase composite strategy. Benefiting from the increased tanδm, an effective absorption bandwidth of 7.0 GHz is achieved for the FC22/paraffin absorber at a thin thickness of 1.45 mm, exhibiting great application advantages in the MA field.

Microstructured Polyfluoroacrylate Elastomeric Dielectric Layer for Highly Stretchable Wide-Range Capacitive Pressure Sensors.

Capacitive pressure sensors capable of replicating human tactile senses have garnered tremendous attention. Introducing microstructures into the dielectric layer is an effective approach to improve the sensitivity of the sensors. However, most reported processes to fabricate microstructured dielectric layers are complicated and time-consuming and usually have adverse effects on the mechanical properties. Herein, we report a mechanically strong and highly stretchable dielectric layer fabricated from a microstructured fluorinated elastomer with a high dielectric constant (5.8 at 1000 Hz) via a simple and low-cost thermal decomposition process. Capacitive pressure sensors based on this microstructured fluorinated elastomer dielectric layer and soft ionotronic electrodes illustrate an impressing stretchability (>300%), a high pressure sensitivity (17 MPa-1), a wide detection range (70 Pa-800 kPa), and a fast response time (below 300 ms). Moreover, the multipixel capacitive pressure sensors sensing array maintains the unique spatial tactile sensing performance even under significant tensile deformation. It is believed that our microstructured fluorinated elastomer dielectric layer might find wide applications in stretchable ionotronic devices.

Effective degradation of Rhodamine B using α-MoO3 nanoplates synthesised using thermal decomposition method

MoO3 nanoplates were effectively synthesized using simple thermal decomposition method and comprehensively characterized for structural, optical, dielectric properties. Structural analysis, primarily through x-ray diffraction (XRD), unequivocally confirmed the orthorhombic phase of the synthesized MoO3 nanoplates, establishing their crystalline structure. The optical properties of MoO3 nanoplates were investigated using UV- Vis diffused reflectance spectra, revealing an optical bandgap of 3.0 eV. Photoluminescence (PL) analysis uncovered sub-band transitions within the nanoplates, shedding light on their luminescent behavior and further emphasizing their optical properties. Raman spectroscopy reaffirmed the orthorhombic structure of the MoO3 nanoplates, providing additional structural confirmation. Morphological and compositional analyses, carried out through field emission scanning electron microscopy (FESEM) and energy dispersive x-ray spectroscopy (EDS), showcased the formation of self-assembled hexagonal plate-like structures. This unique morphology holds promise for various applications, especially in photocatalysis. Dielectric and alternating current (AC) conductivity studies confirmed the semiconducting nature of MoO3 nanoplates, a crucial characteristic for their utilization in electronic devices and catalytic processes. Based on these results photocatalytic activity of the synthesized MoO3 was tested for the degradation of Rhodamine- B in aqueous solution. The complete degradation of Rhodamine B obtained demonstrates the efficacy of MoO3 as a photocatalyst, demonstrating its efficacy in environmental remediation and water purification.

Facile Synthesis and Multiple Application of Ultralong-Afterglow Room Temperature Phosphorescence Aggregate Carbon Dots from Simple Raw Materials.

Owing to the ultralong afterglow, room temperature decay phosphorescence nanomaterials have aroused enough attention. In the work, by simple one-pot solid-state thermal decomposition reaction, aggregate carbon dots (CDs) was prepared from trimesic and boric acid. Based on the intermolecular hydrogen bonds and intramolecular π-π stacking weak interaction from precursors, CDs was encapsulated in boron oxide matrix and formed aggregation. The aggregate state of CDs facilitated the triplet excited states (Tn), which could induce the room temperature decay phosphorescence properties. By careful investigation, under different excitation wavelengths at 254 and 365nm, the aggregate CDs showed > 15s and > 3s room temperature phosphorescence emission in the naked eye, which was associated with 1516.12 ms and 718.62 ms lifetime respectively. And the aggregate CDs exhibited widespread application in encoding encryption, optical anti-counterfeiting and fingerprint identification etc. The interesting aggregate CDs revealed unexpected ultralong-afterglow room temperature decay phosphorescence properties and the work opened a window for constructing ultralong-afterglow room temperature decay phosphorescence aggregate CDs nanomaterials.

Multi-metal interaction boosts reconstructed FeCoCrCuOx@CF toward efficient alkaline water electrolysis under large current density

Electrolysis of water is one of most promising technologies for green hydrogen production. However, the green hydrogen has a market of 4 % only, as the key-component for the technology, electrocatalyst, is expensive, inefficient or unstable. Herein, we design a series of multi-metal oxides (FeCoOx@CF, FeCoCrOx@CF, FeCoCuOx@CF, and FeCoCrCuOx@CF) on cobalt foams to achieve the high efficiency, low cost, and long-term stability by a simple thermal decomposition and electrochemical activation. Among them, FeCoCrCuOx@CF shows remarkable catalytic activity with an ultra-low overpotential (40 mV at 10 mA cm−2) and Tafel slope (27.3 mV dec−1) for hydrogen evolution reaction (HER), which is superior to most reported transition-metal catalysts and comparable to commercial Pt/C, because of the synergistic effect of multiple metals and strong Cr-OH interaction on the reconstructed surface as induced by the dynamic dissolution and redeposition process in the reaction. In addition, the catalyst shows excellent long-term stabilities for HER and overall water splitting at 500 mA cm−2. Importantly, FeCoCrCuOx@CF has the excellent activity and high stability (100 h with only 2 % increment in applied voltage) in the industrial working environment (6 M KOH, ∼ 60 °C). Most importantly, only 3.18 V is needed to obtain > 30 A on a large size electrode for AWE (16.5 cm2, ∼ 1.84 A cm−2) in the industrial conditions. Our findings should provide novel strategies for the design of efficient and stable catalysts toward industrial water electrolysis.

Recovery of high‐purity‐4‐chloroguaiacol from bleaching wastewater by a heterogeneous extraction method

AbstractBACKGROUNDDuring the pulping and bleaching processes, 4‐chloroguaiacol accounts for a large proportion of chlorine containing pollutants. In this study, a heterogeneous extraction method for extracting 4‐chloroguaiacol from the bleaching wastewater by using the intermediate as the solid phase extraction agent is proposed.RESULTSThe solid intermediate with the molar ratio of 4‐chloroguaiacol to calcium 2:1 is firstly prepared. It is used for reacting with the crude 4‐chloroguaiacol in the bleaching wastewater to generate the end solid complex with the molar ratio of 4‐chloroguaiacol to calcium 4:1. It is verified to be that the high‐purity 4‐chloroguaiacol can be released from the simple thermal decomposition of the end solid complex.CONCLUSIONAt an optimum extraction condition including 30 °C reaction temperature, the pH value of 7, using the deionized water as the solvent, the extraction yield and the purity of 4‐chloroguaiacol reached 89.2% and 97.8%. Furthermore, after 15 cycle extraction times, the extraction rate of 4‐chloroguaiacol can still reach 86.3%. The extraction yield and the purity of 4‐chloroguaiacol reached 68.15% and 99.56% when the guaiacol content was lower than 25 mg/L at the bleaching wastewater. © 2023 Society of Chemical Industry (SCI).

Preparation and properties of Gd2O3–Eu2O3–ZrO2 ceramics as promising control rod material

Gray control rods enable the safe operation of nuclear reactors by controlling and adjusting nuclear reactivity, in which neutron-absorbing materials with low reactive worth loss play an important role. In this work, new types of Gd2O3–Eu2O3–ZrO2 ceramics used as neutron absorbers are successfully prepared by simple thermal decomposition following the air sintering method. The cross-sectional SEM images and density curves of ceramics are analyzed, and the ceramic with a content of 85 wt% Eu2O3 sintered at 1500 °C presents a higher density (7.193 g/cm3) than other samples. When the content of Eu2O3 is 70 wt%, the Vickers hardness of the sintered ceramic is 4.89 GPa, which is higher than 4.01 GPa of Eu2O3 (sintered at 1500 °C). This material, which is easy to prepare and has good properties, is regarded as a potential reactor control rod material.

Simultaneous Imaging and Photodynamic-Enhanced Photothermal Inhibition of Cancer Cells Using a Multifunctional System Combining Indocyanine Green and Polydopamine-Preloaded Upconversion Luminescent Nanoparticles.

This work introduces a novel multifunctional system called UPIPF (upconversion-polydopamine-indocyanine-polyethylene-folic) for upconversion luminescent (UCL) imaging of cancer cells using near-infrared (NIR) illumination. The system demonstrates efficient inhibition of human hepatoma (HepG2) cancer cells through a combination of NIR-triggered photodynamic therapy (PDT) and enhanced photothermal therapy (PTT). Initially, upconversion nanoparticles (UCNP) are synthesized using a simple thermal decomposition method. To improve their biocompatibility and aqueous dispersibility, polydopamine (PDA) is introduced to the UCNP via a ligand exchange technique. Indocyanine green (ICG) molecules are electrostatically attached to the surface of the UCNP-polydopamine (UCNP@PDAs) complex to enhance the PDT and PTT effects. Moreover, polyethylene glycol (PEG)-modified folic acid (FA) is incorporated into the UCNP-polydopamine-indocyanine-green (UCNP@PDA-ICGs) nanoparticles to enhance their targeting capability against cancer cells. The excellent UCL properties of these UCNP enable the final UCNP@PDA-ICG-PEG-FA nanoparticles (referred to as UPIPF) to serve as a potential candidate for efficient anticancer drug delivery, real-time imaging, and early diagnosis of cancer cells. Furthermore, the UPIPF system exhibits PDT-assisted PTT effects, providing a convenient approach for efficient cancer cell inhibition (more than 99% of cells are killed). The prepared UPIPF system shows promise for early diagnosis and simultaneous treatment of malignant cancers.

Highly selective photocatalytic CO 2 reduction to ethylene in pure water by Nb 2O 5 nanoparticles with enriched surface –OH groups under simulated solar illumination

Photocatalytic CO₂ reduction to valuable chemical compounds could be a promising approach for carbon neutral practice. In this work, a simple and robust thermal decomposition process was developed with ammonium carbonate as both the precipitation agent and sacrificial template to produce fine Nb₂O₅ nanoparticles with a rich existence of surface -OH groups. It was found by Density Functional Theory (DFT) calculations and experiments that the rich existence of surface -OH groups enhanced the adsorption of both reactants (CO₂ and H₂O molecules) for the photocatalytic CO₂ reduction on these fine Nb₂O₅ nanoparticles, and a highly selective conversion of CO₂ to a high value chemical compound of ethylene (~ 68 mmol·g^-1·h^-1 with ~ 100% product selectivity) was achieved under simulated solar illumination without the usage of any sacrificial agents or noble metal cocatalysts. This synthesis process may also be readily applied as a surface engineering method to enrich the existence of surface -OH groups on various metal oxide-based photocatalysts for a broad range of technical applications.

Numerical simulations of flame spread in pine needle beds using simple thermal decomposition models

Computational fluid dynamics (CFD) models have increased in use for studying scenarios relevant to wildland fires, such as examination of the driving processes in flame spread in vegetative fuels. However, these tools utilize a complex set of submodels which require a large number of input parameters. Often the full set of fuel-specific parameters are not well-quantified and the user must rely upon the best available information. In this study, we examine the implications of using different simple models for thermal decomposition when simulating flame spread through a bed of dead pine needles in quiescent conditions. Model results using one set of common literature values are compared to those using data from milligram-scale characterizations of the fuel. An updated model for char oxidation is also implemented and tested. It was found that the literature values over-predicted mass loss rate by a factor of 2.4, while the fuel-specific values yielded predictions within the experimental uncertainty. A simple approach to decomposition modeling was also shown to be useful for investigating the role of bed structure on flame spread and the heat flux within the fuel bed.

Polymerization-Induced Aggregation Approach toward Uniform Pd Nanoparticle-Decorated Mesoporous SiO2/WO3 Microspheres for Hydrogen Sensing

Hydrogen as an important clean energy source with a high energy density has attracted extensive attention in fuel cell vehicles and industrial production. However, considering its flammable and explosive property, gas sensors are desperately desired to efficiently monitor H2 concentration in practical applications. Herein, a facile polymerization-induced aggregation strategy was proposed to synthesize uniform Si-doped mesoporous WO3 (Si-mWO3) microspheres with tunable sizes. The polymerization of the melamine-formaldehyde resin prepolymer (MF prepolymer) in the presence of silicotungstic acid hydrate (abbreviated as H4SiW) leads to uniform MF/H4SiW hybrid microspheres, which can be converted into Si-mWO3 microspheres through a simple thermal decomposition treatment process. In addition, benefiting from the pore confinement effect, monodispersed Pd-decorated Si-mWO3 microspheres (Pd/Si-mWO3) were subsequently synthesized and applied as sensitive materials for the sensing and detection of hydrogen. Owing to the oxygen spillover effect of Pd nanoparticles, Pd/Si-mWO3 enables adsorption of more oxygen anions than pure mWO3. These Pd nanoparticles dispersed on the surface of Si-mWO3 accelerated the dissociation of hydrogen and promoted charge transfer between Pd nanoparticles and WO3 crystal particles, which enhanced the sensing sensitivity toward H2. As a result, the gas sensor based on Pd/Si-mWO3 microspheres exhibited excellent selectivity and sensitivity (Rair/Rgas = 33.5) to 50 ppm H2 at a relatively low operating temperature (210 °C), which was 30 times higher than that of the pure Si-mWO3 sensor. To develop intelligent sensors, a portable sensor module based on Pd/Si-mWO3 in combination with wireless Bluetooth connection was designed, which achieved real-time monitoring of H2 concentration, opening up the possibility for use as intelligent H2 sensors.