SnO2 Nanorods Research Articles

Biosynthesis of the Ag Doped SnO2 Nanorods Supported Bentonite Clay with Enhanced Photocatalytic Activity Against Crystal Violet Dye

Biosynthesis of the Ag Doped SnO2 Nanorods Supported Bentonite Clay with Enhanced Photocatalytic Activity Against Crystal Violet Dye

Construction of Ba-doped Ag3PO4/SnO2 type-II nanocomposites as a promising photocatalyst for boosting photocatalytic degradation of BY28 dye and redox conversion of Cr(VI)/Cr(III)

In the present study, Ba-doped Ag3PO4/SnO2 type-II heterojunction nanocomposites were fabricated and systemically investigated for the degradation of basic yellow 28 (BY28) dye and Cr(VI) reduction in the photocatalytic process under visible-light irradiation. XRD, XPS, FESEM, DRS, and PL analyses were performed to determine the characterization of synthesized photocatalysts. The optimal 1.5 wt% Ba-doped Ag3PO4/SnO2 nanocomposite exhibited an efficient photocatalytic activity with rate constant of 0.0491 min−1 for BY28 degradation and 0.0261 min−1 for Cr(VI) reduction, which is 13.3 and 7.5 times higher than that of the SnO2 nanorods. Such enhanced performance can arise from the one-dimensional structure, extended light absorption toward the visible region, formation of the type II heterojunction, the new defect-related energy states, and efficient charge separation. Furthermore, the photostability of the photocatalysts was studied and a plausible photocatalytic mechanism was proposed.

Flower-like SnO2 nanorod aggregates modified with Co3O4 nanoparticles grown on reduced graphene oxide(rGO) sheets for xylene sensing

In this paper, the ternary composite of flower-like SnO2 nanorod aggregates modified with Co3O4 nanoparticles grown on rGO sheets were synthesized by a two-step process of water heating and water bath, and characterized by SEM, TEM, XRD, EDS, and XPS. The gas-sensitive performance test results revealed that the 15-rGO/SnO2/Co3O4 sensor exhibited a higher response value (I0/Ia=24.46) to 100 ppm xylene at the optimal working temperature of 175℃. In addition, the sensor could detect 10 ppb xylene, with a low detection limit. The gas-sensitive properties of 15-rGO/SnO2/Co3O4 were significantly improved due to the large specific surface area of rGO flakes and SnO2 slender nanorods, the catalytic action of p-type semiconductor Co3O4 and the existence of p-n-p double heterojunction. Due to the special nanostructure and synergistic effect of SnO2, rGO and Co3O4, the 15-rGO/SnO2/Co3O4 sensor enabled the efficient and selective detection of xylene.

NO2 gas-sensing enhancement by selective laser surface treatment of SnO2 nanorods

A new surface engineering technology has been introduced that can dramatically change the morphology and composition of existing SnO2 nanorods (NRs) to SnOx nanobeads (NBs) + NRs with the addition of a 1–6s laser + convex lens pair (LCP) process. Unlike the existing flame chemical vapour deposition (FCVD) method, which has a two-dimensional effect on a sample, LCP can control a relatively local area with a radius of several microns, making it a more sophisticated and advanced process. Notably, the LCP process at each second was directly linked to the change in the composition of the surface of the SnO2 NRs, and the response to NO2 gas in the SnO2 NBs + NRs with 1second LCP process was improved by approximately three times compared to that of bare SnO2 NRs. Therefore, a new gas-sensing mechanism was proposed through comparing the types of oxygen defect on the SnO2 NRs surface during a slight morphological transition and thermodynamic data of the composition before and after gas sensing.

Strategic Ni integration to study its impact on the photoluminescence and photocatalytic performances of SnO2 nanorod architecture

The sol-gel process was utilized to fabricate SnO2 nanoparticles, both in their pure form and with the addition of Ni dopants. The nanoparticles obtained were further examined to ascertain the characteristics associated with their structure, alterations in band gap, and photocatalytic performance. The insertion of nickel ions into tin sites hinders the formation of grain growth in tin oxide. The variation in the valence states and ionic radius of Sn4+ and Ni2+ ions, as revealed by X-ray diffraction (XRD) study, accounts for this disparity. FTIR measurements indicate the existence of stretching vibrations of metal-oxygen bonds that include Ni ions in the doped samples. The photoluminescence (PL) analysis reveals that the introduction of nickel doping alters the band structure of SnO2, leading to the creation of additional defect states, such as oxygen vacancies inside the crystal lattice. A study was undertaken to investigate the photocatalytic (PC) activity of SnO2 in the presence of Ni dopants. The results revealed a noticeable improvement in the efficiency of photodegradation. The degradation of Congo red (CR) dye using Ni–SnO2 nanocrystals achieves an efficiency of 94.88 % within a duration of 180 ​min. An analysis has been conducted on the impact of dye content, photocatalyst dosage, and pH on the degradation efficiency. As per the study, lower dose of Ni–SnO2 has shown better degradation efficiency in comparison to other studies. The improved performance of Ni–SnO2 can be ascribed to two main factors: the inhibition of carrier recombination due to the inclusion of defective states, and the production of hydroxyl radicals (OH•). The stability and reusability of these photocatalysts have been noted in their efficient application for environmental remediation.

Investigating dual-functional Al-doped stannic oxide nanorods towards photodegradation of real industry wastes and dye-sensitized solar cell application: An experimental and theoretical interpretation

In this work, we demonstrate a uniquely designed Tin (IV) Oxide (SnO2)-based nanomaterials for energy and environmental applications. Here, the Al-doped SnO2 nanorods (NR) at various concentrations ranging from 3 wt% to 9 wt% carried out following facile co-precipitation technique which induced synergic structural, optical and electrical properties in resulting products. Further, the Al-incorporation induced considerable changes to the structural, optical, and electrical characteristics turning SnO2 nanorods to Al-SnO2 nanocubes (NCs). Resulting changes from nanorod to nanocubes were closely monitored using various characterization techniques, which were then effectively utilized for photocatalytic degradation of important textile industry dyes, encompassing both cationic (MB, CV) and anionic (EBT) types. Optimal Al-doped SnO2 NC (6 wt%) demonstrated significant degradation efficiencies for organic pollutant and textile industry effluents under direct sunlight exposure. On the other hand, combination of optical and electrical properties was utilized in dye-sensitive solar cells (DSSCs) to achieve noteworthy efficiency of 6.33%, surpassing that of previous reported SnO2-based nanostructures. These exceptional performance nanomaterials can be attributed to the optimized morphology of the nanocubes and the reduction of the band gap from 3.24 eV to 2.75 eV facilitated by the introduction of aluminum dopant. Furthermore, synergic combination has also improved visible light excitation, substantially decreased resistance to charge carrier transfer phenomenon, improved the charge carrier concentration, as well as considerably decreased the electron/hole recombination rate. Therefore, presence of Al in SnO2 nanostructure has considerably improved the opto-electrical properties that were interpreted following theoretical studies. Therefore, study gives simple nanomaterials having both the photodegradation and dye-sensitive solar cell (DSSC) performance of the SnO2 nanostructure, as a cost-effective energy conversion and water pollution remediation tool for the near future.

Magnetic Fe3O4 nanospheres supported N/S-SnO2 nanorod for highly effective visible light photocatalytic degradation of tetracycline

The global health landscape is increasingly threatened by antimicrobial resistance, prompting a search for pioneering interventions. The current study focused on the construction of non-metal doped SnO2 nanorod decorated with Fe3O4 nanospheres through hydrothermal techniques. The prepared N/S-SnO2@Fe3O4 nano-heterojunction was evaluated by performing photocatalytic degradation of tetracycline (TET) under visible light illumination. Out of various combinations tested, S-SnO2@Fe3O4 nano-heterojunction was found to degrade TET by 98.3% with a TOC removal of 97%. S-SnO2@Fe3O4 nano-heterojunction and its constituents were characterized by using TEM, SEM, XRD, DRS, PL, Raman, XPS, EIS, BET and FTIR. The influence of factors such as pH, ions, S-SnO2@Fe3O4 dosage and TET concentration on photodegradation were investigated. Furthermore, the stability and reusability of S-SnO2@Fe3O4 nano-heterojunction were assessed through six consecutive cycles of TET photodegradation. XPS and XRD analyses characterized the recovered nano-heterojunction, while scavenging assays and ESR analysis identified as •OH is the main reactive oxygen species involved in TET photodegradation. Additionally, GC-MS/MS analysis proposed a photodegradation pathway, and ECOSAR was used to predict the toxicity of intermediates.

Switching and control mechanism between p-type and n-type in SnO2 nanorods using laser with added convex lens to control oxygen concentrations

In a significant advancement, a novel technology has been developed to precisely control the electronic sensitization of SnO2 nanorods. This control is accomplished in a matter of seconds through the external injection of energy via laser and convex lens pairs (LCP). Utilizing LCP, selective redox reactions can be induced on the surface of SnO2 nanorods. The study focused on the contrasting effects of NO2, an oxidizing gas, and H2, a reducing gas. In the presence of NO2, the electronic sensitization caused by LCP outweighs the chemical sensitization due to NO2, thereby resulting in both n-type and p-type behaviors. In contrast, when exposed to H2, the nanorods exhibit only n-type behavior, as the chemical sensitization effect of H2 is more significant than the electronic sensitization effect of LCP. The observed variations in electronic properties can be systematically accounted for by the differential bonding energies between oxidizing and reducing gases.

Single-source thermal deposition of (BA)2(MA)3Pb4I13 perovskite for a novel SnO2NRs/comp-TiO2@ irradiated-ITO based 2D/3D perovskite solar cell: Comparative study of irradiated ITO layer and its effect on device performance

Perovskite solar cells have achieved very good efficiency but their stability is still a big issue. To achieve an efficient a stable perovskite solar cell; a new simple single source thermal evaporation approach has been used to deposit 2D/3D (BA)2(MA)3Pb4I13 perovskite active layer, for realization of novel architecture of stable perovskite solar cell. Bi ions irradiated ITO electrode, coated with compact TiO2 and SnO2 nano-rods (NRs) layers, has been used as ETL. A unique approach is adopted to deliberately place SnO2 NRs horizontally on the surface comp-TiO2 coated irradiated ITO. Four, SnO2NRs/comp-TiO2@ irradiated-ITO based 2D/3D perovskite devices, have been fabricated with 1.2 GeV Bi ions irradiated ITO, at four different fluences (1.3 × 1011, 6.5 × 1011, 1.3 × 1012 and 2.6 × 1012 ions/cm2). Nano-hillocks formed by irradiation proved to contribute for the better performance to a certain point. It was found that the choice of using horizontally place SnO2-NRs in ETL contributed for better performance and stability of proposed device. Among four fabricated devices highest efficiency of 13.6 % is obtained for ITO irradiated with 1.3 × 1012 ions/cm2 fluence which is very encouraging for 2D/3D hybrid perovskite based solar cells in addition to improved performance all the devices showed good stability.

Confining isolated Pt atoms into the porous SnO2 for efficient gas sensing

Highly dispersed isolated sites offer opportunities to rationally design sensing materials with desired performance, but their stability under harsh reaction conditions is still challenging. Herein, we deposited the highly dispersed atomic layer deposition (ALD) platinum (Pt) species into optimized porous SnO2 nanorods derived from the Sn-based metal organic frameworks (MOFs). With confining isolated Pt into porous SnO2, the optimum operating temperature of the sensor based on SnO2–Pt2 nanorods was decreased from 275 °C to 190 °C. And the response (Ra/Rg) to 5 ppm acetone was improved from 2.63 to 6.33, along with the decrease of response time from 23 s to 9 s. Combined with X-ray adsorption, near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) and density functional theory (DFT) simulation, the highly dispersed Pt confined within SnO2 nanorods are confirmed to heighten the adsorption of acetone at working temperature and lower the reaction activation energy. The confined structure enriches the acetone in hole, further enhancing its adsorption on Pt. The highly dispersed isolated Pt sites and confined effects dramatically promote the sensing performance. The understanding of structure-activity relationships offers a novel strategy to design the ultrasensitive and stable acetone sensing materials, and it shows potential applications in design of other gas sensing or catalytic materials.

Hydrogenation effect on 2D ZnO single crystal/ZnO–SnO2 two phase ceramics and its enhanced mechanism in H2 gas sensing

In this work, a 1D/2D two-phase structure of ZnO single-crystal nanosheets/ZnO–SnO2 nanorods was constructed, and the hydrogen gas sensing properties including selectivity have been enhanced by this low-cost way without noble metal doping. It was proved that hydrogenation effect on ZnO (0001) single crystal facets was the key to forming the low resistance surface in hydrogen gas, leading significantly enhancement in response and selectivity. The response (Ra/Rg) to 200 ppm hydrogen gas exceeded 400 at a low operating temperature of 150 °C, response/recovery time in 100 ppm H2 was only 30 s/8 s. The sensor also has good selectivity for hydrogen detection. The enhancement in gas sensing properties due to dual mechanism of the hydrogenated low-resistance surface and the resistance modulation of ZnO/SnO2 heterojunctions, which proposed in this paper.

Efficient visible-light-driven photocatalytic performance for nitrogen oxide abatement application in the air by a typical metal/semiconductor heterojunction

To improve the photocatalytic oxidation activity of SnO2 nanorods, we decorated Ag nanoparticles onto SnO2 nanorods via a photoreduction route at low temperature. The metal/semiconductor heterojunction based on Ag/SnO2 nanorods indicated a high photocatalytic activity towards NO gas removal in visible light region at the air conditions. Detailly, the NO photocatalytic removal performance of Ag/SnO2 heterojunctions are significantly enhanced, achieving 50.6 % after 30 min, approximately 1.9 times higher than that of SnO2 nanorods. In addition, the Ag/SnO2 heterojunctions have a lower NO2 gas conversion efficiency of 1.0 %, while pure SnO2 nanorods have a high NO2 conversion efficiency of 5.2 %. Moreover, photogenerated holes play a crucial role in the photocatalytic activity of NO gas removal.

Isobutanol gas sensor based on Fe2O3–SnO2 heterostructure nanostructure

The rough surface Fe2O3–SnO2 composite nanorod material was prepared by electrostatic spinning. The morphology and nanostructure of Fe2O3–SnO2 composite nanorods were characterized by scanning electron microscopy SEM, nitrogen physical adsorption and X-ray diffraction. Through the analysis of the test results, it can be shown that the Fe2O3–SnO2 nanorod samples prepared in this experiment have the advantages of high purity, good crystallinity and large specific surface area. The specific surface area of the sample obtained from the test is 19.27 m2/g. According to the gas sensitivity test results of Fe2O3–SnO2 nanorods, it can be seen that Fe2O3–SnO2 samples have high responsiveness and excellent gas sensitivity selectivity. Various gases were tested in this experiment, and it was found that the sensor has good gas selectivity to isobutanol. At 310 °C, the sensor's response to 100 ppm isobutanol reached 13. This experiment not only prepared Fe2O3–SnO2 nanorod sensor with good isobutanol gas sensitivity. And it realized the accurate measurement of continuous isobutanol concentration. In addition, the gas sensitivity mechanism of Fe2O3–SnO2 nanomaterials was discussed.

Fe-doped BiVO4 photocatalyst assisting SnO2 nanorod arrays for efficient visible-light-driven degradation of Basic Red 46

BackgroundDesigning and constructing heterogeneous structures is an effective approach employed to improve photocatalytic performance. This study aimed to use Fe-doped BiVO4/SnO2 nanocomposites for photocatalytic degradation of Basic Red 46 (BR46) dye under visible-light irradiation. MethodsBiVO4 nanoparticles doped with varying amounts of Fe were synthesized using the sol-gel method and interspersed on SnO2 nanorods with an average diameter of about 100 nm fabricated using the liquid phase deposition (LPD) process. FE-SEM, EDX, XRD, FT-IR, XPS, BET, DRS, and PL analysis were used to characterize the morphology and structure of the samples. Significant findingsThe 1.5 wt% Fe-doped BiVO4/SnO2 nanocomposite exhibited the highest visible-light photoactivity with excellent stability, resulting in complete degradation of BR46 within 90 min of irradiation. The boost photocatalytic activity of Fe-doped BiVO4/SnO2 nanocomposite can be attributed to the enhanced separation of photo-generated carriers derived from synergistic effects by the BiVO4/SnO2 heterostructure, Fe doping in BiVO4 lattice, and partly the extended light absorption ability. These findings show that designing a heterogeneous BiVO4/SnO2 structure with Fe-doping can be a promising strategy for the application in constructing efficient and stable photocatalysts for the degradation of dyes from industrial wastewater pollutions.

Highly sensitive and selective detection of benzene, toluene, xylene, and formaldehyde using Au-coated SnO2 nanorod arrays for indoor air quality monitoring

We report the high performance of Au-coated SnO2 nanorod gas sensors for the detection of hazardous indoor volatile organic compounds (VOCs), such as benzene, toluene, xylene, and formaldehyde (BTXF) gases. Densely ordered SnO2 nanorod arrays were prepared via glancing angle deposition with an electron beam evaporator. The Au layer coating was used as a heterogeneous catalyst to promote the oxidation of VOCs, such as hydrocarbons. After optimizing the Au thickness, the sensor exhibited an excellent sensing response and a rapid response time of < 2.5 s for 10 ppm of BTXF gases. The maximum response was ∼662 for formaldehyde at 400 °C, ∼328 for toluene at 450 °C, ∼170 for xylene at 400 °C, and ∼139 for benzene at 500 °C, which are significantly higher than those of previously reported metal-oxide-semiconductor-based sensors. Each gas was selectively detected by integrating the sensor into a miniaturized gas chromatography (GC) system. The sensors detected ppb-level gas concentrations. Significantly, GC analysis revealed that four types of gases could be separately detected in a mixed gas within 5 min. Our study shows that Au-coated SnO2 nanorod gas sensors integrated with GC can be used as a facile indoor pollutant monitoring system.

Highly stable and reversible hydrogen sensors using Pd-coated SnO2 nanorods and an electrode–substrate interface as a parallel conduction channel

We demonstrated highly stable and reversible H2 sensors using a dual electron-conduction channel comprising Pd-coated SnO2 nanorods (NRs) and a parallel conduction channel containing Cr/native oxide/p-type Si interface. The dual-channel sensor exhibited highly reversible resistance changes during H2 in-and-out cycles at operating temperatures of 25 °C− 100 °C, while typical single-channel sensors with SnO2 NRs fabricated on SiO2 (300 nm)/Si substrates showed irreversible response because of insufficient recovery from Pd-Hx to Pd-Ox. In particular, the sensor showed significantly high repeatability, long-term stability, and selectivity for H2 sensing at 80 °C. Additionally, the time taken to detect H2 above 1% was less than 2 s and the response to H2 above 500 ppm was unaffected by high humidity. These results indicate that the dual-channel Pd-coated SnO2 NR sensor is suitable for applications such as hydrogen leak detectors that require high speed and precision. Moreover, it was found that the sensor could detect H2 below 0.5 ppm even at low temperatures. This work provides a pathway for improving gas-sensing performance by interface engineering, enabling various practical hydrogen sensor applications.

Covalently grafting porphyrin on SnO2 nanorods for hydrogen evolution and tetracycline hydrochloride removal from real pharmaceutical wastewater with significantly improved efficiency

The sensitization of a wide-gap oxide semiconductor with a strong visible-light-absorbing porphyrin has been evidenced as a promising approach to craft highly efficient photocatalysts towards photocatalytic hydrogen evolution and environmental remediation. However, the practical utilization of porphyrins-sensitized oxide catalysts relies on the integration mode between porphyrins and metal oxide. Herein, a novel high-performance porphyrin-sensitized oxide catalyst is constructed via covalent assembling of copper porphyrin derivative of 5-(4-azidophenyl)-10,15,20-triaminoporphyrin (CuTPP–N3) on SnO2 nanorods by click reaction for the first time. The optimized 10 %CuTPP-N3/SnO2 hybrid demonstrates remarkably enhanced photocatalytic activity in H2 evolution of 658.6 μmol g−1h−1. It is almost 78 times higher than that of pristine SnO2. It also exhibits great potential for eliminating tetracycline hydrochloride (TCH) from various aqueous solutions with high durability under visible-light irradiation. Its removal rates in deionized water, tap water and real pharmaceutical wastewater are 90.5%, 72.2% and 85%, respectively. It is almost 13 times higher than that of pristine SnO2 nanorods in deionized water. The experimental evidence indicates that the highly conjugated linker between CuTPP–N3 and SnO2 plays a critical role for facilitating photoinduced electron transfer ability. This forms an efficient Z-scheme carrier transmission system in the hybrid. Therefore, the present work affords a well-designed molecule-engineered chromophore/oxide hybrid for highly efficient application in hydrogen evolution and environmental remediation.

Effects of Reaction Conditions on the Morphology and Property of Sb Doped SnO2 Nanorods Anode

Effects of Reaction Conditions on the Morphology and Property of Sb Doped SnO2 Nanorods Anode

Morphology control of Ce-doped SnO2 and enhanced microwave absorbing performance at 2−18 GHz

Semiconductor metal oxides are widely used in the field of wave absorption because of their easily tunable dielectric properties. Doping or modulating the morphology has been demonstrated to be an effective method to improve the microwave (MW) absorbing performance of semiconductor metal oxides. In this study, Ce-doped SnO2 was prepared by a simple and effective coprecipitation method. Single-crystal SnO2 nanorods were generated during the doping process and the size of the nanorods could be controlled by modifying the concentration of Ce. The presence of nanorods greatly enhances the MW absorbing performance: when the doping molar ratio is 3%, the minimum reflection loss of the absorber is −77.91 dB at a frequency of 13.79 GHz with a thickness of 1.6 mm and the maximum effective absorbing bandwidth is 4.47 GHz at a thickness of 1.5 mm. Excellent MW absorbing performance of Ce-doped SnO2 is attributed to its excellent impedance matching and interfacial polarization.

Highly sensitive H2S gas sensor containing simultaneously UV treated and self-heated Ag-SnO2 nanoparticles

A gas sensor to detect H2S gas based on SnO2 nanorods (NRs) and Ag doped SnO2 nanoparticles (NPs) was fabricated by growing SnO2 NRs on an interdigitated Au substrate and spin coating Ag doped SnO2 NPs on the NRs’ surface. The morphology, chemical, optical, and electrical properties of this nanostructure were examined using FESEM, EDAX, XRD, PL and absorption spectroscopy. The fabricated sensor was further enhanced by doping the SnO2 NPs with Ag as well as utilizing an innovative method of simultaneous exposure to UV illumination and self-heating. The proposed design has proven to reduce the destructive effect of humidity due to its photocatalytic properties. This unique nanostructure design enhanced the sensing response of the device from 2.7 to 8 (in the detection range of 500 ppb-10 ppm). This improvement caused by an increase of the electron injection on the NPs’ interfaces and a multiplication of the available active sites on which H2S gas is trapped. In addition, the sensor’s response and recovery time toward 10 ppm H2S gas increased from 11 and 14 s to 5 and 8 s respectively. The sensor’s cross-sensitivity toward C6H6, C2H5OH, CO2, and NH3 was also examined to determine the selectivity.