Tin oxide based nanostructured materials: synthesis and potential applications

In view of their inimitable characteristics and properties, SnO₂ nanomaterials and nanocomposites have been used not only in the field of diverse advanced catalytic technologies and sensors but also in the field of energy storage such as lithium-ion batteries and supercapacitors, and in the field of energy production such as solar cells and water splitting. This review discusses the various synthesis techniques such as traditional methods, including processes like thermal decomposition, chemical vapor deposition, electrospinning, sol-gel, hydrothermal, solvothermal, and template-mediated methods and green methods, which include synthesis through plant-mediated, microbe-mediated, and biomolecule-mediated processes. Moreover, the advantages and limitations of these synthesis procedures and how to overcome them that would lead to future research are also discussed. This literature also focuses on various applications such as environmental remediation, energy production, energy storage, and removal of biological contaminants. Therefore, the rise and journey of SnO₂-based nanocomposites will motivate the modern generation of chemists to modify and design robust nanoparticles and nanocomposites that can effectively tackle significant environmental challenges. This overview concludes by providing future perspectives on research into tin oxide in synthesis and its various applications.

Facile Synthesis of BiVO4@ZIF-8 Composite with Heterojunction Structure for Photocatalytic Wastewater Treatment

Water pollution has always been a serious problem across the world; therefore, facile pollutant degradation via light irradiation has been an attractive issue in the field of environmental protection. In this study, a type of Zn-based metal–organic framework (ZIF−8)-wrapped BiVO₄ nanorod (BiVO₄@ZIF−8) with high efficiency for photocatalytic wastewater treatment was synthesized through a two-step hydrothermal method. The heterojunction structure of BiVO₄@ZIF−8 was confirmed by morphology characterization. Due to the introduction of mesoporous ZIF−8, the specific surface area reached up to 304.5 m²/g, which was hundreds of times larger than that of pure BiVO₄ nanorods. Furthermore, the band gap of BiVO₄@ZIF−8 was narrowed down to 2.35 eV, which enabled its more efficient utilization of visible light. After irradiation under visible light for about 40 min, about 80% of rhodamine B (RhB) was degraded, which was much faster than using pure BiVO₄ or other BiVO₄-based photocatalysts. The synergistic photocatalysis mechanism of BiVO₄@ZIF−8 is also discussed. This study might offer new pathways for effective degradation of wastewater through facile design of novel photocatalysts.

Synthesis of SnO2 nanofibers and nanobelts electron transporting layer for efficient perovskite solar cells

The implementation of positive alternative electron transporting layers (ETLs) with excellent electronic properties is a most promising method to up-scale low-cost highly efficient perovskite solar cell (PSC) technology. The present work demonstrates the preparation of tin oxide (SnO2) nanofibers (NF) and nanobelts (NB) as an electron transporting layer (ETL) for PSCs. The smooth and uniform nanofibers and nanobelts have been prepared using an electrospinning technique followed by calcination at 600 °C. Thermogravimetric analysis (TGA) analysis performed on the as-spun polyvinylpyrrolidone-tin oxide (PVP-SnO2) composite suggests that a calcination temperature of 600 °C is required to obtain pure SnO2 and to ensure complete removal of PVP along with other organic solvents. The structural analysis confirmed the presence of the pure tetragonal rutile phase of SnO2 nanofibers and nanobelts. The prepared nanofibers and nanobelts were further used as ETLs for PSCs. Our optimized experimental parameters yielded a JSC of 22.46 mA cm-2, a VOC of 1.081 V and FF of 66%, leading to >16% power conversion efficiency (PCE) for SnO2 nanobelts using an (FAPbI3)0.85(MAPbI3)0.15 perovskite absorber layer with good stability. The obtained PCE is much higher than that of the SnO2 NF (12.893%) morphology. Nevertheless, the synthesis of SnO2 NF/NB ETLs provides a simple, low-cost and large-scale method for PSCs.

Polyol asserted hydrothermal synthesis of SnO2 nanoparticles for the fast adsorption and photocatalytic degradation of methylene blue cationic dye

Schematic representation of the photocatalytic degradation of MB dye using the SnO₂ nanocatalyst.

Fabrication of SnO₂-reduced graphite oxide monolayer-ordered porous film gas sensor with tunable sensitivity through ultra-violet light irradiation

A new graphene-based composite structure, monolayer-ordered macroporous film composed of a layer of orderly arranged macropores, was reported. As an example, SnO₂-reduced graphite oxide monolayer-ordered macroporous film was fabricated on a ceramic tube substrate under the irradiation of ultra-violet light (UV), by taking the latex microsphere two-dimensional colloid crystal as a template. Graphite oxide sheets dispersed in SnSO₄ aqueous solution exhibited excellent affinity with template microspheres and were in situ incorporated into the pore walls during UV-induced growth of SnO₂. The growing and the as-formed SnO₂, just like other photocatalytic semiconductor, could be excited to produce electrons and holes under UV irradiation. Electrons reduced GO and holes adsorbed corresponding negative ions, which changed the properties of the composite film. This film was directly used as gas-sensor and was able to display high sensitivity in detecting ethanol gas. More interestingly, on the basis of SnO₂-induced photochemical behaviours, this sensor demonstrated tunable sensitivity when UV irradiation time was controlled during the fabrication process and post in water, respectively. This study provides efficient ways of conducting the in situ fabrication of a semiconductor-reduced graphite oxide film device with uniform surface structure and controllable properties.

Facile synthesis of ZnO–C nanocomposites with enhanced photocatalytic activity

ZnO–C nanocomposites exhibit excellent photocatalytic activity towards methylene blue degradation.