SnO2 Materials Research Articles

Enhancement of Dye Sensitized Solar Cell Efficiency Using Chlorophyll as Dye Sensitizer by Adding The SnO2 Material to TiO2

Dye-Sensitized Solar Cell (DSSC) is the third generation of solar cells. DSSC is formed by sandwich structure, there are five parts: ITO glass (Indium Tin Oxide) as the substrate; TiO2 and SnO2 as semiconductor material; natural dye from chlorophyll as an electron donor; gel electrolyte as electron transfer and active carbon as a catalyst in the counter electrode. The synthesis of nanometer-sized TiO2 powder is obtained by coprecipitation method. The layer of TiO2 was deposited on top of an ITO glass by doctor blade method. From the research, the DSSC efficiency has increased by nearly 100% after additions SnO2 to TiO2. The DSSC efficiency result is 0.05% for DSSC before additions and 0.1% after additions

The effects of oxide additives on the mechanical characteristics of Ag–SnO2 electrical contact materials

The effects of oxide additives such as WO3, Cu2O, In2O3, etc. on the mechanical characteristics of Ag-8wt.%SnO2 contact materials were investigated. The tensile tests of the Ag–SnO2 materials prepared by powder metallurgy method were carried out on a MZ.Ms tensile machine. The fracture morphologies of the tensile samples were studied by a Scanning Electron Microscope (SEM). The fracture mechanism was simulated and analyzed utilizing ANSYS software. The results revealed that the addition of oxide additives increased the ultimate strengths and elasticity moduli of the Ag-8wt.%SnO2 contact materials. The maximum strength was achieved on the sample with addition of Cu2O, which reached up to 134.6 MPa. The stress concentration around SnO2 particles was relaxed with adding oxide additives. The initiation and propagation of the intergranular cracks in Ag–SnO2 contact materials were inhibited. Accordingly, the plasticity and creep resistance of the prepared materials were markedly improved. It was interesting that no visible intergranular cracks were generated in the Ag-8wt.%SnO2 contact materials when the SnO2 particles were decreased to about 70 nm. The mechanical properties of the Ag-8wt.%SnO2 nanocomposites were dramatically improved by adding In2O3. The mechanism was quite different from the Ag–SnO2 materials containing micron-sized SnO2 particles.

VOCs gas sensing properties on SnO2 (110) surface with dissociated oxygen species pre-adsorbed: experiments and DFT analysis

SnO2 nanoparticle material was synthesized and used to fabricate MHP based gas sensor, which showed better gas sensing performance to ethanol than the other target gases. DFT calculation and analysis for the gas adsorption properties on SnO2(110) surface were conducted thoroughly by mean of DMol3 package in Materials Studio software to yield insight into the surface-adsorbate interactions of SnO2 material. Firstly, the pre-adsorption of oxygen on SnO2 (110) surface was modeled and analyzed, it was proved that the spontaneous adsorption O2 molecule and O atom could take place more easily on SnO2 (110) reductive surface than SnO2 (110) oxidative surface, and O2 molecule has more obvious tendency to be dissociated when adsorbed on SnO2 (110) reductive surface. Secondly, in consideration of the actual existence of oxygen vacancy, the pre-adsorption of oxygen on SnO2 (110) reductive surface with oxygen vacancy was conducted. The dissociation and ionization of O2 molecule were observed when molecular oxygen was adsorbed above the in-plane oxygen vacancy vertically on SnO2(110) reductive surface, which further verified the spontaneous adsorption of O2 molecule and the assumption for O− or O2− species. At last, the VOC gases adsorption properties including ethanol, methanol, formaldehyde and so on were carried out, the results revealed that ethanol was the easiest to be adsorbed on SnO2 material and hence might show better gas sensing properties than the other target gases, which is broadly in line with the experimental data.

MPL/GDL-Supported Pt Electrocatalysts for PEFCs

Introduction Currently, Pt electrocatalysts supported on carbon black (Pt/C) are widely used in polymer electrolyte fuel cells (PEFCs). However, carbon corrosion can occur on the cathode side especially during start-stop cycles, leading to performance degradation of PEFCs (1). To solve this technological issue, we have developed SnO2 and TiO2 support materials dispersed on graphitized carbon materials acting as the conductive backbone, exhibiting high durability (2-4). Here in this study, we focus on non-carbon support such as Nb-doped TiO2 which is stable under both anode and cathode conditions. In addition, we prepared various electrocatalyst layers directly on the microporous layer (MPL) coated on the gas diffusion layer (GDL) to simplify membrane electrode assembly (MEA) structure and manufacturing processes. Non-carbon support was deposited on the MPL/GDL by using arc plasma deposition (APD), and Pt catalyst nanoparticles are then deposited on this porous substrate to prepare a “Pt/non-carbon support/MPL/GDL” structure, as schematically shown in Fig. 1. MEAs can be prepared just by heater-pressing this integrated structure with the polymer electrolyte membrane. Experimental By using APD, various non-carbon support materials were deposited on the MPL/GDL structure, and then Pt catalysts were deposited on it to prepare “Pt/non-carbon support/MPL/GDL” structures. Their microstructure was observed by scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), and transmission electron microscopy (TEM). Electrochemical measurements were performed with single cells. Their performance was measured and compared by varying preparation conditions such as voltage of APD or types of GDL used. Results and discussion Figure 2 shows a STEM image of the Pt/Ti(Nb)O2/MPL/GDL structure after 100 APD pulses for Ti(Nb)O2 support and 500 pulses for Pt catalyst by APD. Pt particles of a few nm in average diameter on the MPL/GDL were observed. Figure 3 shows I-V characteristics of MEAs with the Pt/Ti(Nb)O2/MPL/GDL structure, in which Pt was deposited on the MPL/GDL by 70, 100, and 150V of APD. I-V characteristics of an MEA with the standard Pt/C catalyst (Tanaka Kikinzoku, TEC10E20E) are also shown for comparison, with the common cathode Pt loading of 0.024 mgPt/cm2. For this considerably low Pt loading, higher cell performance was obtained in case Pt was deposited by 100V of APD. Further improvement in electrochemical performance is however needed to realize such catalyst-integrated MPL/GDL structures. Acknowledgment Financial support by the Center-of-Innovation program, JST Japan, is gratefully acknowledged.

The preparation and photoelectric performance of MSe2/SnO2 (M = Mo,W) nanocomposites

Theoretical calculations were combined with experiments to explore the photoelectric catalytic performance of MSe2/SnO2 (M = Mo,W) nanocomposites. The electronic structures of the composites were studied by density functional theory(DFT) calculation. Compared with SnO2 material (1.070 eV), the band gap values of MSe2/SnO2 (M = Mo,W) nanocomposites were significantly reduced to 0.133 and 0.008 eV, respectively. Population analysis suggested that the charges transferred between upper MSe2 (M = Mo,W) and underlying SnO2, which could improve the photoelectric catalytic performance of SnO2 materials. Thus, the MSe2/SnO2 (M = Mo,W) nanocomposites were synthesized by hydrothermal method and characterized by XRD. Electrodeposition was conducted to prepare the corresponding electrodes with Fluorine-doped Tin Oxide (FTO) conductive glass to test the photoelectric catalytic performance. The experimental results showed that the photocurrents of the MSe2/SnO2 (M = Mo,W) nanocomposites were 4.8 and 3.0 μA/cm2, respectively, and the electrochemical impedance was both smaller than that of SnO2 material. Therefore, the MSe2/SnO2 (M = Mo,W) nanocomposites are good photoelectric catalytic materials.

Improving the lithium storage performance of SnO2 nanoparticles by in-situ embedding into a porous carbon framework

Wide attention has been recently paid to the potential application of nanosized SnO2 material in lithium-ion batteries as a new high performance anode owe to its high theoretical specific capacity and moderate working potential. However, the intrinsic problems, such as pronounced volume change and low conductivity, make the capacity decay quickly and rate capability behave badly, therefore severely hindering the practical application of nanosized SnO2 in lithium-ion batteries. Herein, to improve the electrochemical performances, SnO2 nanoparticles have been in-situ embedded into a characteristic porous carbon framework via a facile strategy to form SnO2 nanoparticles/porous carbon framework composite (SnO2 NPs@PC). The as-fabricated SnO2 NPs@PC has three main advantages in lithium storage: Firstly, the good conductive porous carbon framework provides SnO2 with adequate free space (pores) for accommodation of volume change, as well as enhance the conductivity of whole composite; Secondly, the SnO2 NPs@PC with a individual porous architecture has more surface active sites for electrochemical reaction and accessorial contact interfaces between electrode and electrolyte; Finally, the ultrafine SnO2 nanoparticles would have shortened electrons/lithium-ions diffusion distances compared to their bulk counterparts. As a result, the SnO2 NPs@PC gets robust structural stability and improved electrochemical kinetics, therefore exhibits outstanding performances, revealing capacities of 730 and 564 mAh g−1 at 200 and 1000 mA g−1 after 400 and even 1000 cycles, respectively. By comparison with the control samples of pure SnO2 NPs and SnO2 NPs@C, it is demonstrated that the electrochemical performances of SnO2 nanoparticles embedded in a well-designedly peculiar porous carbon framework (SnO2 NPs@PC) have been improved significantly.

Hierarchical structure assembled from in-situ carbon-coated porous tin dioxide nanosheets towards high lithium storage

Wide attention has been recently paid to the potential use of SnO2 material in lithium-ion batteries (LIBs) as a new high performance anode owe to its advantages such as high theoretical specific capacity and moderate working potential. However, the intrinsic problems such as pronounced volume change and low conductivity make the capacity decay quickly and rate capability behave badly, therefore severely hindering the practical application of SnO2 in LIBs. Two-dimensional materials with unique physicochemical properties have gained great attention in energy storage and conversion field, and considered as promising candidates for advanced anode materials of LIBs. Herein, we demonstrate a one-pot hydrothermal and subsequently carbonized approach to prepare a hierarchical structure assembled from in-situ carbon-coated porous tin dioxide (SnO2) nanosheets (SnO2@C NSs). By comparison with similar hierarchical structure assembled from pure SnO2 nanosheets indicates that the in-situ carbon coating significantly improves the electrochemical performances of SnO2@C NSs in terms of stability of structures and kinetics of electrochemical reactions. Consequently, the SnO2@C NSs demonstrates superior electrochemical performances, revealing high reversible capacity of 1077.6 and 730 mAh g−1 at 200 and 1000mAg−1 after 160 and 800cycles, respectively, as well as outstanding rate capabilities. Thus, the as-prepared SnO2@C NSs with excellent performances exhibits good potential to be a promising candidate of advanced anode materials for LIBs. Additionally, this paper may provide a new insight to synthesize fine porous SnO2 nanosheets/carbon composites.

Inexpensive methodology for obtaining flexible SnO2-single-walled carbon nanotube composites for lithium-ion battery anodes

A versatile and low-cost methodology for fabricating free-standing carbon graphite (CG)/SnO2/single-walled carbon nanotube (SWCNT) composites as anode material for lithium-ion batteries is described. CG–SnO2 (1:1) was ball milled and the composite obtained was dispersed with different ratios (wt%) of SWCNT. Then, the flexible composite CG–SnO2–SWCNT was successfully manufactured by a simple vacuum filtration procedure. Electrochemical measurements demonstrated that the anode composite paper with 50 wt% CG–SnO2 and 50 wt% SWCNT showed excellent retention of a high specific capacity (318 mA h g−1) after 30 cycles at current density of 0.08 mA cm−2, which was twice that of SWCNT paper (155 mA h g−1). This SWCNT–CG–SnO2 combination is very promising, since the SWCNT could act as a flexible mechanical support, while CG–SnO2 provides high capacity. This paper presents an inexpensive methodology that may be applied to the design of electrodes and evaluates the interaction between SnO2 and carbon materials as anode in lithium-ion battery systems.

In-situ Grown SnO2 Nanospheres on Reduced GO Nanosheets as Advanced Anodes for Lithium-ion Batteries.

Nanostructured tin dioxide (SnO2) has emerged as a promising anode material for lithium‐ion batteries (LIBs) due to its high theoretical capacity (1494 mA h g−1) and excellent stability. Unfortunately, the rapid capacity fading and poor electrical conductivity of bulk SnO2 material restrict its practical application. Here, SnO2 nanospheres/reduced graphene oxide nanosheets (SRG) are fabricated through in‐situ growth of carbon‐coated SnO2 using template‐based approach. The nanosheet structure with the external layer of about several nanometers thickness can not only accommodate the volume change of Sn lattice during cycling but also enhance the electrical conductivity effectively. Benefited from such design, the SRG composites could deliver an initial discharge capacity of 1212.3 mA h g−1 at 0.1 A g−1, outstanding cycling performance of 1335.6 mA h g−1 after 500 cycles at 1 A g−1, and superior rate capability of 502.1 mA h g−1 at 5 A g−1 after 10 cycles. Finally, it is believed that this method could provide a versatile and effective process to prepare other metal‐oxide/reduced graphene oxide (rGO) 2D nanocomposites.

Colloidal synthesis of Y-doped SnO2 nanocrystals for efficient and slight hysteresis planar perovskite solar cells

It is well known that the electron-transporting layers (ETLs) play an indispensable role in any types of high efficient perovskite solar cells (PSCs) because of their important functions in extracting/transporting electrons and blocking holes during the light-to-electricity conversion process. High quality ETLs are necessary for preparing efficient planar PSCs because the electron diffusion length is shorter than its hole counterpart in perovskite materials and the planar PSCs have short electrons extracting channels due to the lack of mesoporous layers. Recently, impressive advances in planar PSCs with SnO2 ETLs have been reported due to the perfect characteristics of SnO2 material including suitable energy level, high electron mobility, good transmittance, excellent chemical stability, inactive UV photocatalysis, and so on. Here, we use the doping route to further enhance the quality of SnO2 ETLs. The SnO2 nanocrystals are doped with Y3+ through the typical solvothermal method. The Y dopant leads to more suitable energy level structure and better charge carrier dynamics in the devices than those of the undoped ones. The planar PSCs with Y-SnO2 ETLs achieve a champion efficiency of 20.71% with slight hysteresis, much higher than the undoped ones (18.08%).

Long-Range Charge Extraction in Back-Contact Perovskite Architectures via Suppressed Recombination

Summary Metal-halide perovskites are promising solution-processable semiconductors for efficient solar cells with unexpectedly high diffusion ranges of photogenerated charges. Here, we study charge extraction and recombination in metal-halide perovskite back-contact devices, which provide a powerful experimental platform to resolve electron- or hole-only transport phenomena. We prepare polycrystalline films of perovskite semiconductors over laterally separated electron- and hole-selective materials of SnO2 and NiOx. Upon illumination, electrons (holes) generated over SnO2 (NiOx) rapidly transfer to the buried collection electrode, leaving holes (electrons) to diffuse laterally as majority carriers in the perovskite layer. Under these conditions, we find recombination is strongly suppressed. Resulting surface recombination velocities are below 2 cm s−1, approaching values of high-quality silicon. We find diffusion lengths exceed 12 μm, an order of magnitude higher than reported in vertically stacked architectures. We fabricate back-contact solar cells with short-circuit currents as high as 18.4 mA cm−2, reaching 70% external quantum efficiency.

Well dispersed SnO2 nanoclusters preparation and modulation of metal-insulator transition induced by ionic liquid

Tin dioxide (SnO2) has attracted broad interest due to its particular gas-sensor property. Nano- or atom-scale SnO2 material has always been the aim in order to ultimately improve the sensitivity. However, until now, it remains difficult to synthesize SnO2 nanoclusters by using traditional methods. In the present work, we have achieved the preparation of SnO2 nanoclusters by using the cluster beam deposition technique. The obtained nanoclusters were well characterized by high resolution transmission electron microscope HR-TEM. Results indicated the formation of the well-dispersed SnO2 nanoclusters with uniform size distribution (5–7 nm). Furthermore, an obvious metal insulator transition was observed by gating with ionic liquid. Combined with theory calculation, the corresponding mechanism was systematically analyzed from oxygen vacancy induced electron doping.

SnS2/SnO2 Heterostructures towards Enhanced Electrochemical Performance of Lithium–Sulfur Batteries

Lithium-sulfur (Li-S) batteries have been recognized as outstanding candidates for energy storage systems due to their superiority in terms of energy density. To meet the requirements for practical use, it is necessary to develop an effective method to realize Li-S batteries with high sulfur utilization and cycle stability. Here, a strategy to construct heterostructure composites as cathodes for high performance Li-S batteries is presented. Taking the SnS2 /SnO2 couple as an example, SnS2 /SnO2 nanosheet heterostructures on carbon nanofibers (CNFs), named C@SnS2 /SnO2 , were designed and synthesized. Considering the electrochemical performance of SnS2 /SnO2 heterostructures, it is interesting to note that the existence of heterointerfaces could efficiently improve lithium ion diffusion rate so as to accelerate the redox reaction significantly, thus leading to the enhanced sulfur utilization and more excellent rate performance. Benefiting from the unique structure and heterointerfaces of C@SnS2 /SnO2 materials, the battery exhibited excellent cyclic stability and high sulfur utilization. This work may provide a powerful strategy for guiding the design of sulfur hosts from selecting the material composition to constructing of microstructure.

Fabricating thin two-dimensional hollow tin dioxide/carbon nanocomposite for high-performance lithium-ion battery anode

Both thin two-dimensional (2D) and hollow nanostructural materials are of great potential for high-performance anodes of lithium-ion batteries owing to their unique structural properties and surface characteristics. In this context, tin dioxide (SnO2) materials possessing well-designed thin 2D or hollow nanostructures have attracted immense attention and been considered as promising candidates to serve as anodes for advanced lithium-ion batteries. It is believed that thin 2D hollow nanostructures of SnO2 materials will have the advantages of both thin 2D and hollow nanostructures but they are difficult to be prepared due to the increased complexity of structures. Herein, a peculiar thin 2D hollow nanostructure of SnO2/carbon (SnO2/C) composite, composed of carbon in-situ coating thin SnO2 hollow nanosheets, has been prepared through a well-designed strategy. It is thus clear that this composite possesses the advantages of both thin 2D and hollow nanostructures as an anode for lithium-ion batteries. Expectedly, it is demonstrated that thus peculiar architecture offers the as-prepared SnO2/C composite superior electrochemical kinetics and outstanding structural stability. As a result, the as-prepared SnO2/C composite exhibits outstanding electrochemical lithium storage performance, delivering 707.8 and 483.2 mAh g−1 after 100 cycles at 200 and 1000 mA g−1, respectively, as well as superior rate capabilities.

High-Response Room-Temperature NO2 Sensor and Ultrafast Humidity Sensor Based on SnO2 with Rich Oxygen Vacancy.

SnO2 nanosheets with abundant vacancies (designated as SnO2- x) have been successfully prepared by annealing SnSe nanosheets in Argon. The transmission electron microscopy results of the prepared SnO2 nanosheets indicated that high-density SnO2- x nanoplates with the size of 5-10 nm were distributed on the surface of amorphous carbon. After annealing, the acquired SnO2- x/amorphous carbon retained the square morphology. The stoichiometric ratio of Sn/O = 1:1.55 confirmed that oxygen vacancies were abundant in SnO2 nanosheets. The prepared SnO2- x exhibited excellent performance of sensing NO2 at room temperature. The response of the SnO2- x-based sensor to 5 ppm NO2 was determined to be 16 with the response time and recovery time of 331 and 1057 s, respectively, which is superior to those of most reported room-temperature NO2 sensors based on SnO2 and other materials. When the humidity varied from 30 to 40%, Δ R/ R was 0.025. The ultrafast humidity response (52 ms) and recovery (140 ms) are competitive compared with other state-of-art humidity sensors. According to the mechanistic study, the excellent sensing performance of SnO2- x is attributed to its special structure.

Carambola-shaped SnO2 wrapped in carbon nanotube network for high volumetric capacity and improved rate and cycle stability of lithium ion battery

Constructing nanostructures of high capacity materials and hybridizing the same with conductive carbon networks are important for high performing lithium ion batteries. Here, we demonstrate new carambola-shaped crystalline SnO2 (c-SnO2), which is wrapped in a three-dimensional multiwalled carbon nanotube network (c-SnO2@3D-CNT). The carambola structure of c-SnO2 is constructed by changing the surface energy of a specific crystalline plane using a potassium fluoride capping agent. The as-designed c-SnO2@3D-CNT achieves a high capacity of 1140.2 mA·h·g−1 at 50 mA·g−1, a capacity retention of 50.7% retained at 1000 mA·g−1 relative to 50 mA·g−1, and a cycling stability of 72.0% over 500 cycles at a high rate of 1000 mA·g−1. In particular, the c-SnO2@3D-CNT shows a high volumetric capacity of 1674.8 mA·h·cm−3 at 50 mA·g−1 and 849.2 mA·h·cm−3 at 1000 mA·g−1, which is greater than those of previous SnO2-based materials. This finding is associated with the compact packing of hierarchical carambola structure having multiple concave surfaces into dense and porous electrode. Therefore, the hierarchical carambola structure and 3D hybrid architecture provide a buffer space for volume expansion and fast ion/electronic conducting pathways, which impart a high volumetric capacity, improved cyclic and rate performances, and higher reversibility than other SnO2 materials.

Stabilizing the reversible capacity of SnO2/graphene composites by Cu nanoparticles

Low electronic conductivity and the tin coarsening caused irreversible capacity loss are the primary cause of poor cycle performances in SnO2 materials. In this work, a ternary SnO2/Cu/graphene composite is synthesized by a one-pot selective reduction method to improve the cycle life of SnO2-based composite anode. During the liquid-phase synthesis process, the Cu2+ and Sn2+ cations are adsorbed uniformly on the surface of GO sheets under electrostatic attraction, which are then selective reduced by N2H4·H2O because of its moderate reduction falling in between these two components (Eϴ(Cu2+/Cu) 0.34 V > Eϴ(Sn2+/Sn) −0.14 V). The electrochemical active SnO2 and inactive Cu nanoparticles anchor tightly on the flexible conductive graphene sheets and locate in close proximity to each other. Cu nanoparticles can promote the charge transfer kinetics of insulating SnO2 at the interfaces, compress the volume stress as lithium ions insertion/deinsertion, and obstruct the aggregation of metallic Sn and LixSn alloy, thus continuously promoting the reversibility of conversion reaction from Sn/Li2O to SnO2. The as-prepared composite displays an excellent long-term cycling stability, delivering a reversible capacity of 890.6 mAh g−1 at 100 mAg−1 even after 200 cycles without any capacity decay. The excellent cyclic stability and facile liquid-phase synthesis method demonstrate the promising candidate of the Cu nanoparticles in stabilizing the reversible capacity of SnO2/graphene composite and its candidate in scalable application.

Synthesis, Photoluminescence and Photocatalytic Activity of Tetragonal SnO2 Prepared by Hydrothermal Sol-Gel Method

Luminescent SnO2 material was synthesized by a hydrothermal assisted sol-gel method. X-ray powder diffraction analysis indicates that the as-synthesized SnO2 is a tetragonal phase and the calculated lattice parameters a and c are 0.474 and 0.318 nm, respectively. Scanning electron microscopy shows that the prepared tetragonal SnO2 particles have regular rhombic shape and are polydisperse without any agglomeration. Ultraviolet-visible absorption spectroscopy was used to study the light-absorbing properties and bandgap of tetragonal SnO2, and the value of bandgap is obtained to be 2.894 eV. The emission spectrum detected at λex = 230 nm showed two peaks located at 375 and 415 nm, the first having the strongest luminescence intensity. The fluorescence emission spectra also show that an emission peak at 510 nm is observed when the λex is 400 nm. Photocatalytic experiments indicate that the tetragonal SnO2 exhibits a strongly enhanced photocatalytic activity than commercial nano-SnO2 in photocatalytic degradation of various dyes under visible light irradiation. The photocatalytic mechanism is discussed on the basis of X-ray photoelectron spectroscopy (XPS) data, Fourier transform infrared (FTIR) spectra, electrochemical measurements and photocatalytic experiments results.

Enhanced lithium storage performances of SnO2 nanospheres induced by Sb dopants

In this work, highly uniform Sb doped SnO2 nanospheres with different Sb doping concentrations were prepared by a hydrothermal method. Compared with the pure SnO2 material, the obtained SnO2:Sb nanospheres exhibits significantly enhanced lithium storage performances in both of the initial capacity and the cycling stability, severed as anode materials for lithium-ion batteries. Among the SnO2:Sb materials provided in this work, the SnO2:Sb nanospheres with 6 at% of Sb dopants delivers a highest discharge capacity of 1575 mA h g−1 (charge capacity of 914 mA h g−1) at the first cycle and excellent cyclability (588 mA h g−1 at 100th cycles), due to the reduced crystalline size and the improved electrical conductivity induced by Sb dopants.

Assembly of high-nuclearity Sn26 , Sn34 -oxo clusters: solvent strategies and inorganic Sn incorporation.

A series of unprecedented high-nuclearity tin-oxo nanoclusters (up to Sn34 ) with structural diversity have been obtained. The characteristics of the applied solvents had great influence on the assembly of these Sn-O clusters. Pure alcohol environments only gave rise to small clusters of Sn6 , whilst the introduction of water significantly increased the nuclearity to Sn26 , which greatly exceeds those of the known tin-oxo clusters (≤14); the use of aprotic CH3CN finally produced the largest Sn34 to date. Apart from the nuclearity breakthrough, the obtained tin-oxo clusters also present new structural types that are not found in previous reports, including a layered nanorod-like structure of Sn26 and the cage-dimer structure of Sn34 . The layered Sn26 clusters represent good molecular models for SnO2 materials. Moreover, an electrode derived from TOC-17 with a {Sn26 } core shows better electrocatalytic CO2 reduction activity than that from TOC-18 with Sn34 . This work not only provides an efficient methodology for the rational assembly of high-nuclearity Sn-O clusters, but also extends their potential applications in energy conversion.