Ternary Metal Oxide Research Articles

γ-Alumina Supported Copper Oxide Nanostructures Promoted with Ruthenium Oxide (RuO2-CuO/Al2O3) and Palladium Oxide (PdO-CuO/Al2O3): Efficient Electrodes for Heterogeneous Catalysis of Ammonia Electrooxidation

RuO2 and PdO promoted CuO/Al2O3 mixed metal oxide nanostructures synthesized via co-impregnation technique demonstrated a robust electrocatalytic activity towards ammonia electro-oxidation (AEO). Physio-chemically characterized RuO2-CuO/Al2O3 and PdO-CuO/Al2O3 catalyst powders exhibited high electrochemical active surface area (ECSA), highest being shown by 1% RuO2-CuO/Al2O3. All fabricated electrodes displayed pleasing electroactive response towards AEO but ternary metal oxides showed superior and promoted catalytic output owing to their larger ECSA, higher current densities (j), larger diffusion coefficients (D°), greater apparent rate constants (kapp), and lower charge transfer resistance (Rct) values. Lower values of Rct obtained from EIS indicated the facilitation of electro-oxidation process over modified electrodes. The finest catalysis performance is expressed by 1% RuO2-CuO/Al2O3 producing the maximum oxidation current. All the promoted CuO/Al2O3 mixed metal oxide exhibited excellent stability and reproducibility in analyte solution. Consequently, γ-Al2O3 supported metal oxide electrocatalysts can be of great socio-economic significance by enhancing the energy production kinetics thereby achieving a higher energy output.

Ternary metal oxide filled PEO-based polymer electrolyte for solid-state lithium metal battery: The role of filler particle size

Composite polymer electrolytes with fillers exhibit appealing properties, such as high ionic conductivity, good flexibility, and low cost. However, poor compatibility and electrochemical instability, especially at high current rates, are the disadvantages of these electrolytes. In this study, we report the influence of particle size of Li2O. SiO2. TiO2. P2O5 (LSTP) on polyethylene oxide (PEO)-matrix towards the fabrication of Li-metal batteries with a LiFePO4 cathode. Compared to micron-sized particles, the high surface area of the nanoparticles in the polymer matrix is beneficial for improved electrochemical stability at 0.1 mA cm−2. Furthermore, the nanosized particulates facilitate faster ionic conductivity (1.09 × 10−3 S cm−1 at 80 °C) and excellent stability at higher voltage >4.5 V. Our results clearly indicate the role of filler morphology in enhancing the ionic conductivity and stability. Finally, the full cell made of metallic Li anode and LiFePO4 cathode displays a capacity of 110 mAh g−1 (after 100 cycles under 1C at 60 °C) with a reasonable cycle life using such a nanocomposite solid polymer electrolyte.

A novel ternary metal oxide cascade Z-scheme heterojunction for efficient CO2 photoconversion without a co-catalyst

Photocatalytic CO2 reduction to produce synthetic fuels has emerged as a promising strategy in the quest for environmentally friendly and sustainable energy sources. Herein, we report a ternary metal oxide cascade Z-Scheme consisting of Cu2O/WO3/CeO2 nano-heterostructures that exhibits 4-fold higher activity towards visible-light-driven photocatalytic CO2 reduction in the absence of noble metal co-catalysts compared to binary oxide components and 8-fold higher than CeO2. The ternary Z-scheme heterojunction shows enhanced visible light absorption, effective separation of photoinduced charge carriers, and enhanced redox capacity due to the synergistic effect of two heterojunctions in Cu2O/WO3/CeO2.

Ternary metal oxide substrates for superconducting circuits

Substrate material imperfections and surface losses are one of the major factors limiting superconducting quantum circuitry from reaching the scale and complexity required to build a practical quantum computer. One potential path towards higher coherence of superconducting quantum devices is to explore new substrate materials with a reduced density of imperfections due to inherently different surface chemistries. Here, we examine two ternary metal oxide materials, spinel (MgAl2O4) and lanthanum aluminate (LaAlO3), with a focus on surface and interface characterization and preparation. Devices fabricated on LaAlO3 have quality factors three times higher than those of earlier devices, which we attribute to a reduction in the interfacial disorder. MgAl2O4 is a new material in superconducting quantum devices, and even in the presence of significant surface disorder, it consistently outperforms LaAlO3. Our results highlight the importance of materials exploration, substrate preparation, and characterization for identifying materials suitable for high-performance superconducting quantum circuitry.

Synthesis of hierarchical mesoporous Ln2Ti2O7 (Ln = Y, Tb–Yb) pyrochlores and uranyl sorption properties

Mesoporous structured metal oxides exhibit many active applications. However, the synthesis of crystalline metal oxides with a ternary composition while maintaining satisfactory pore features is challenging. Typically, high temperatures are required which inhibit control of pore structure properties including surface area, pore volume, and pore size. Herein, the synthesis of ternary metal oxides Ln2Ti2O7 possessing pyrochlore crystal structure is achieved using a novel technique which combines ‘soft’ and hard colloid templating strategies. The formed materials are of submicron size and composed of ∼ 25–30 nm product ‘building blocks’ with good chemical and phase stability. The polycrystalline powders have a high specific surface area (up to 70 m2·g–1) and pore volume (∼ 0.35 cm3·g–1) which result in a good adsorption capacity (U uptake closing to 60 mg·g–1). Remarkably, the material exhibits a significant portion of mesopores (mainly 10–40 nm) which facilitate fast adsorption of the cations due to high accessibility. The synthetic methodology described herein produces highly homogenous powders and can be applied to other compositions and structures.

Novel Copper-Zinc-Manganese Ternary Metal Oxide Nanocomposite as Heterogeneous Catalyst for Glucose Sensor and Antibacterial Activity.

A novel copper-zinc-manganese trimetal oxide nanocomposite was synthesized by the simple co-precipitation method for sensing glucose and methylene blue degradation. The absorption maximum was found by ultraviolet–visible spectroscopy (UV-Vis) analysis, and the bandgap was 4.32 eV. The formation of a bond between metal and oxygen was confirmed by Fourier Transform Infrared Spectroscopy (FT-IR) analysis. The average crystallite size was calculated as 17.31 nm by X-ray powder diffraction (XRD) analysis. The morphology was observed as spherical by scanning electron microscope (SEM) and high-resolution transmission electron microscopy (HR-TEM) analysis. The elemental composition was determined by Energy Dispersive X-ray Analysis (EDAX) analysis. The oxidation state of the metals present in the nanocomposites was confirmed by the X-ray photoelectron spectroscopy (XPS) analysis. The hydrodynamic diameter and zeta potential of the nanocomposite were 218 nm and −46.8 eV, respectively. The thermal stability of the nanocomposite was analyzed by thermogravimetry-differential scanning calorimetry (TG-DSC) analysis. The synthesized nanocomposite was evaluated for the electrochemical glucose sensor. The nanocomposite shows 87.47% of degradation ability against methylene blue dye at a 50 µM concentration. The trimetal oxide nanocomposite shows potent activity against Escherichia coli. In addition to that, the prepared nanocomposite shows strong antioxidant application where scavenging activity was observed to be 76.58 ± 0.30, 76.89 ± 0.44, 81.41 ± 30, 82.58 ± 0.32, and 84.36 ± 0.09 % at 31, 62, 125, 250, and 500 µg/mL, respectively. The results confirm the antioxidant potency of nanoparticles (NPs) was concentration dependent.

In-situ construction of ternary metal oxide heterostructures Mn@LaZrO: A novel multi-functional nanocatalyst for detecting environmental hazardous 4-nitroaniline

The level of environmental pollutants is kept increasing as the continued sources of waste discharges into the ecosystem. The improper discharge of industrial waste products, widely used pesticides in agriculture, and pharmaceutical discharges are the major source of this uplift. Nitro aromatics are one among the major intermediates for producing dyes, pesticides, and fungicides. Monitoring and assessing these environmental pollutants is more important to reduce the consequences experienced by human and aquatic life. Thus, the dual-sensing platform was developed for analyzing the 4-nitroaniline (4-NA) derivative via electrochemical and UV–vis sensing analysis. Inspired by the unique properties of nanomaterials trimetallic oxides as manganese with lanthanum zirconium oxide (Mn@LaZrO) were synthesized. The physicochemical features were determined with different analytical techniques. The Mn@LaZrO was found with pure crystalline nature and nanospheres at nanoplates were identified. The fabricated electrode with Mn@LaZrO was exposed to both the sensing analysis (UV and electrochemical) with 0.049 µM −1443.78 µM and 0.49 µM-159.61 µM linear ranges of 4-NA addition. The higher surface area with more reactive active sites triggered the faster electron transfer rate in 4-NA sensing. The Mn@LaZrO/GCE showed lowered resistance with the Rct value of 117.75 Ω determining the higher electrocatalytic activity of the composite. The LOD was obtained to be 0.003 µM and 0.041 µM. The highly influential factors such as selectivity, repeatability, reproducibility, and stability parameters depicted excellent performances. Thus, the dual-functional Mn@LaZrO executes excellent performances with its unique features.

Ruthenium and palladium oxide promoted zinc oxide nanoparticles: Efficient electrocatalysts for hydrazine oxidation reaction

Development of highly catalyzing electrode materials for hydrazine electrooxidation reaction (HzOR) demands a judicious assortment of intrinsically active candidates, precise engineering of electrodes for enhancement of active sites and building of electronically conductive structures. Herein, we report the novel, innovative and robust heterogeneous electrocatalysts for HzOR for ultimate hydrogen generation and their applicability in direct hydrazine fuel cell (DHFC). The presented catalysts comprised of ZnO microparticles supported on γ-Al2O3 with different weight percentages (10, 20, 30, 40 wt/wt%). Binary catalyst i.e. 20% ZnO/Al2O3 displayed the maximum catalytic output towards HzOR, so it is chosen to further combine with RuO2 and PdO to investigate a promoted and enhanced oxidation output. Ternary metal oxide catalysts i.e. RuO2-ZnO/Al2O3 and PdO-ZnO/Al2O3 with varied contents of RuO2 and PdO (0.1, 0.5 and 1 wt/wt%) are prepared via co-impregnation method. X-Ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy coupled energy dispersive spectroscopy (SEM-EDS), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) are the techniques employed for physio-chemical characterization of samples. Among all the investigated catalysts, 1% PdO-ZnO/Al2O3 produced the most catalyzing behavior toward HzOR owing to its largest diffusion coefficient (50.0 × 10−6 cm2 s−1), highest current density (5.2 mA cm−2) and high ECSA (0.23 cm2). The catalysts showed sufficient reproducibility and stability by scanning multiple cycles and testing similar electrodes after different time intervals. This is the first study of hydrazine electrooxidation protocol employing RuO2 and PdO promoted γ-alumina supported ZnO structured electrocatalysts.

Ternary metal oxide WO3.NiO.ZnO nanoparticles and their composite with CNTs for organic dye photocatalytic degradation

For photocatalytic dye degradation, ternary metal oxides (WO3, ZnO, and NiO) and their nanocomposite with carbon nanotubes (CNTs) were prepared by co-precipitation and ultrasonication route, respectively. X-ray diffraction (XRD) and scanning electron microscopic (SEM) analysis were done to investigate structural properties, phase purity and surface morphology of prepared nanomaterials and their nanocomposites. Fourier Transform Infra-Red (FTIR) spectroscopic analysis was done to investigate functional groups of fabricated metal oxides. The FTIR spectral analysis confirmed the presence of M − O (metal-oxygen) functional groups in the prepared nanomaterials. The nanocomposite of WO3.ZnO.NiO with carbon nanotubes (CNTs) was synthesized to study their behaviour for photodegradation. CNTs have some unique characteristics that are required for advancement of photocatalytic degradation for treating wastewater. Methylene blue (MB) is used as a typical dye in photocatalysis to examine the degradation efficiency of prepared photocatalysts. The rate of methylene blue (MB) degradation rate was 45.87% by WO3.ZnO.NiO nanoparticles and 66.19% by WO3.ZnO.NiO/CNTs nanocomposite in the presence of H2O2. These results showed the increased photocatalytic properties of the prepared nanocomposite in comparison with bare mixed metal oxides.

High Corrosion Resistance of a Ti-Based Anode with Sn/Ti/Nb Ternary Metal Oxide Interlayers.

Ti-based anodes are widely applied in water splitting, the chlor-alkali industry, hydrometallurgy, and organic compound electrochemical synthesis. However, the thickening passivation layer in Ti substrates in acidic electrolytes accelerates the deactivation of whole Ti-based anodes. In order to block the attack from the reactive oxygen species, a compact interlayer containing ternary metal oxides (SnO2, TiO2, and Nb2O5, STN) on Ti foil (denoted as Ti-STN) was prepared via a facile thermal-decomposition method. The SnO2, TiO2, and Nb2O5 components impose the mutual restriction of grain growth during the pyrolytic synthetic progress, which promotes the grain refinement of STN interlayers. Due to the compact and stable STN interlayers, the Ti-STN substrate and the Ti-STN-derived active anodes presented an enhanced corrosion resistance and prolonged service lives. Hence, we believe that the Ti-STN substrate and the grain-refinement method to resist electrochemical corrosion in this work offer new approaches for the development of industrial electrolysis and electrochemical energy conversion devices.

Preparation of yolk–double shell Mn0.5Zn0.5Co2O4/C nanomaterials as anodes for high–performance lithium–ion batteries

Ternary metal oxides have enormous potential in lithium–ion batteries (LiBs) owing to their tunable chemical composition and abundant active sites. In this work, we prepared Mn0.5Zn0.5Co2O4/C nanospheres with a yolk–double shell structure use doping Mn into ZnCo2O4 through a self-templating solvothermal method. The Mn0.5Zn0.5Co2O4/C nanospheres with yolk–double shell structure has a shell–layer thickness of about 34 nm, a carbon layer of 15 nm, and an inner–core diameter of approximately 78 nm. The peculiar yolk–double shell structure effectively can buffer the volume expansion and decrease the diffusion path of Li+, which improves the electrochemical performance. After 100 cycles at a current density of 200 mA g–1, the Mn0.5Zn0.5Co2O4/C nanospheres retained a specific capacity reaching 1001 mA h g–1. Even after 150 cycles at a higher current of 500 mA g–1, the specific capacity remained at 971 mA h g–1. Therefore, as an anode material for LiBs, the Mn0.5Zn0.5Co2O4/C nanospheres show high reversible capacity, superior cycling stability, and excellent electrochemical performance. Compared with ZnCo2O4, in Mn-doped ZnCo2O4, Mn can occupy the octahedral interstices of the spinel structure, which contributes to enhance the pseudocapacitive properties of the anode material, accelerate ion diffusion and improve charge transfer.

Effect of B site substitution in Gd2B2-xNiyO7-δ (B= Ti, Zr) ternary metal oxide catalysts in dry reforming of methane

Structured catalysts are emerging as active and durable catalysts in dry reforming of methane due to their inherent characteristics like lattice insertion of active metals and consequent stability imparted. Here we report Ti and Zr substituted Gd2B2-xNiyO7-δ (B = Ti, Zr) catalysts synthesized by citrate gel method, which are characterized and tested for dry reforming of methane. Structure and Ni substitution has been confirmed by Rietveld refinement of powder XRD patterns and Raman analysis. TPR and CO2-TPD were performed to analyze the reducibility and effect of basic sites of catalysts in DRM activity. Ni doped Ti analogue shows stable and superior activity towards dry reforming of methane for 100 h. The in situ IR studies and XPS analysis confirmed the presence of surface hydroxyl species in this catalyst, which triggers the activation of CO2 and provides higher and durable activity in dry reforming reaction. Absence of any C formation in this catalyst after durability test indicates the mechanism of C gasification by the surface hydroxyl species enhancing stable activity for long durations.

Double-shelled hybrid MgFe2O4/Fe2O3 hollow microspheres as a high-capacity anode for lithium-ion batteries

Ternary metal oxides Fe2O3 and MgFe2O4 have attracted considerable attention as lithium anode materials owing to their high theoretical capacities, environmental friendliness, and low cost; however, their rapid capacity decay and large volume expansion inhibit their lithium storage performance. Herein, we synthesize hybrid MgFe2O4/Fe2O3 hollow microspheres (MFO/FO-HS) hydrothermally, via the polyol reaction of ethylene glycol, followed by calcination at different temperatures. The surface morphology was tuned by adjusting the calcination temperature, assisted by inward and outward Ostwald ripening. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and thermogravimetric analysis were performed to investigate the physio-chemical properties of the prepared samples. The sample calcined at 450 °C exhibited an excellent electrochemical performance and retained a reversible capacity of 1390 mAh g−1 after 160 cycles, indicating the significant role of calcination temperature in tuning the structural and electrochemical properties of anode materials. The double-shelled hollow microspheres inhibit rapid capacity decay and prevent severe volume expansion during the electrochemical process. This work opens new paths toward constructing an electrode material with a high electrochemical performance.

Hosting AlCl3 on ternary metal oxide composites for catalytic oligomerization of 1-decene: Revealing the role of supports via performance evaluation and DFT calculation

Enhancing catalytic activity and stability of supported Lewis acid catalysts remain a particular challenge owing to the limited understanding and unsatisfactory tuning of the interplay between the active components and the supports. Herein, upon immobilizing AlCl3 on a series of ternary metal oxides including La2O3–Al2O3–SiO2, NiO–Al2O3–SiO2 and Ga2O3–Al2O3–SiO2, we clearly revealed the influence of the compositions and structures of the supports on the catalyst performances through experiments together with density functional theory (DFT) calculations. The catalytic performances of the supported samples were evaluated by oligomerization of 1-decene using both batch reactor and fixed-bed apparatus. The results suggest that the AlCl3 supported by NiO–Al2O3–SiO2 composites exhibits the highest catalytic activity and stability because of its positive pore structure and thereof the high loading of active species. Importantly, DFT calculations indicate that the variations of the host-guest interaction energy between the ternary oxide composites and AlCl3 are in good agreement with the experimental results. This study highlights the compositions and structures of the supports are crucial to the catalytic performances of Lewis acid catalysts, and provides fundamental guidance for design of high-performance supported catalysts.

Self-template formation of porous yolk-shell structure Mo-doped NiCo2O4 toward enhanced lithium storage performance as anode material

• Mo-doped NiCo 2 Co 4 was prepared in yolk-shell structure with a porous core. • The anode exhibited highly reversible capacity and excellent rate performance. • The pathway of Li + transportation was shortening by yolk-shell structure. • Electrolyte infiltration was enhanced by providing more active surface. Hollow ternary metal oxides have shown enormous potential in lithium-ion batteries (LIBs), which is ascribed to their complex chemical composition, abundant active defect sites, and the synergy effect between metals. In this work, we synthesized Mo-doped NiCo 2 O 4 porous spheres with yolk-shell structure by using a simple self-templating method. Surprisingly, other than the yolk-shell structure we had obtained, the inner core of the yolk-shell was also porous, which could fully enhance the electrolyte infiltration and promote the transmission of lithium ions (Li + ) and electrons (e − ). The diameter of the porous core in the yolk-shell sphere was about 530 nm, and the outer shell's thickness was up to 110 nm. In addition, the unique pores in the core appeared in the diameter of about 85 nm. With this structure, the volume expansion of the anode could be well inhibited during charge/discharge. It exhibited prominent electrochemical performance with high reversible capacity (1338 mA h g −1 at 100 mA g −1 ), satisfactory cycle life (1360 mA h g −1 after 200 cycles at 100 mA g −1 ), and exceptional rate capability (820 mA h g −1 at 2000 mA g −1 ) as anode material in LIBs.

Novel ternary metal oxide nanoparticles (La2Cu0.8Zn0.2O4) as a potential photocatalyst for visible light photocatalytic degradation of methylene blue and desulfurization of dibenzothiophene

In this work we present the preparation of novel ternary metal oxide nanoparticles, La2Cu0.8Zn0.2O4 (LCZO), using a simple co-precipitation method. The crystalline structure, morphology and composition of the prepared LCZO nanoparticles were characterized by x-ray diffraction, scanning electron microscopy and energy-dispersive x-ray analysis. The diffuse reflectance spectrum investigation showed that LCZO nanoparticles have considerable light absorption in the visible light region. Also, the LCZO nanoparticles possess a band-gap energy of 2.82 eV. To investigate the visible light photocatalytic potential of the prepared LCZO nanoparticles, two photocatalytic reactions were conducted, namely degradation of methylene blue (MB) solution and desulfurization of dibenzothiophene (DBT). In the presence of a 3:1 molar ratio of H2O2/DBT, a high photocatalytic desulfurization rate of DBT (93.7%) was obtained over 0.2 g of LCZO photocatalyst. In addition, the photocatalytic degradation rate of MB solution was 91.4%. The mechanisms of both photocatalytic reactions were studied using different radical scavenging agents, which showed that hydroxyl radicals are responsible for highly efficient desulfurization and degradation reactions. Moreover, reusability experiments reveal that the prepared LCZO photocatalyst has great stability and recyclability for both desulfurization of DBT and degradation of MB after six reaction cycles.

Using ZnCo2O4 nanoparticles as the hole transport layer to improve long term stability of perovskite solar cells

Inorganic metal oxides with the merits of high carrier transport capability, low cost and superior chemical stability have largely served as the hole transport layer (HTL) in perovskite solar cells (PSCs) in recent years. Among them, ternary metal oxides have gradually attracted attention because of the wide tenability of the two inequivalent cations in the lattice sites that offer interesting physicochemical properties. In this work, ZnCo2O4 nanoparticles (NPs) were prepared by a chemical precipitation method and served as the HTL in inverted PSCs. The device based on the ZnCo2O4 NPs HTL showed better efficiency of 12.31% and negligible hysteresis compared with the one using PEDOT:PSS film as the HTL. Moreover, the device sustained 85% of its initial efficiency after 240 h storage under a halogen lamps matrix exposure with an illumination intensity of 1000 W/m2, providing a powerful strategy to design long term stable PSCs for future production.

Urchin like inverse spinel manganese doped NiCo2O4 microspheres as high performances anode for lithium-ion batteries

The ternary transition metal oxides are promising anode material for lithium-ion batteries (LIBs). However, their practical applications are greatly hindered by the poor conductivity and huge volume changes. To solve the issues, urchin-like inverse spinel manganese (Mn) doped NiCo2O4 hierarchical microspheres were fabricated through a facile hydrothermal approach and subsequent annealing treatment. The as-obtained Mn-doped NiCo2O4 hold microsphere and sharp fiber-shaped needle multilevel nanoscale architecture, which effectively shortened Li ions (Li+) transmission path and improved the conductivity. In addition, the hierarchical urchin-like Mn-doped NiCo2O4 synthesized at annealing temperature (600 °C) manifested a larger capacity and better cycling performance by controlling the crystallinities and morphologies. As expected, it displays an outstanding cycling performance with a reversible capacity of about 945 mAh g−1 after 500 cycles at 2000 mA g−1. The kinetic analysis and galvanostatic intermittent titration technique (GITT) testing also verifies the superior pseudocapacitance contribution and fast elevated ion migration of Li+. Our work provides a promising design to develop suitable anode materials based on transition metal oxides for high-performance LIBs.

Cobalt-based metal oxide coated with ultrathin ALD-MoS2 as an electrode material for supercapacitors

A novel approach of preparing a composite supercapacitor electrode consisting of ternary metal oxide nanostructure decorated with transition metal sulfide is presented. High-surface area NiCo2O4 nano-sheets grown on Ni-foam are coated with an ultrathin layer of MoS2 by atomic layer deposition (ALD) and the hybrid structure reveals superior electrochemical performance. The composite is thoroughly studied with several characterizations like XRD, Raman, XPS, SEM and TEM. A comparative study with MoS2 coated Co3O4 electrodes not only ensures the advantage of the more conducting sulfide layer in enhancing the supercapacitor performance significantly but also establishes the superiority of the ternary oxide (NiCo2O4) for this application. The thinner and well-connected nano-sheets of NiCo2O4 provides the more interface between the electrode and the electrolyte whereas an optimal thickness of MoS2 helps to maximize the performance of the device. The high areal capacitance (2445 mF cm−2), enhanced rate capability of the optimized NiCo2O4-MoS2 composite is therefore ascribed to the synergistic effect of high-surface area of the oxide nano-sheets and better electronic conductivity of the sulfide. The current study thus opens a route to combine the conventional hydrothermal synthesis of ternary oxide nanostructures with ALD grown layered transition metal dichalcogenides to achieve a superior electrode for next-generation supercapacitor.

Enhanced photoelectrochemical performances in photocatalytic pollutant degradation and water splitting by direct Z-scheme Bi2Sn2O7/TiO2 NTAs

The construction of ternary metal oxide to improve photoelectrochemical performances of TiO2 photocatalysts is the hot topic in environmental and resource applications. Herein, Bi2Sn2O7 nanoparticles were deposited on TiO2 nanotube arrays (TiO2 NTAs) by the solvothermal technology only by changing reagent concentration. The solar absorption region of TiO2 NTAs was obviously extended into visible light after Bi2Sn2O7 sensitization, and the photoelectric performance was also significantly improved. The high visible light photocurrent density and photovoltage achieved 30.24 μA/cm2 and -0.19 V, and the interface resistance was reduced that benefited the rapid electron transportation. The photocatalytic performances of methyl orange (MO), rhodamine b (RhB), methylene blue (MB) and Cr (VI) removal were enhanced, and 63.76%, 77.34%, 100% and 100% of these pollutants were photoremoved under solar irradiation. Moreover, the construction of direct Z-scheme Bi2Sn2O7/TiO2 NTAs heterojunction was beneficial to the photoelectron transfer and active radical formation, and the experimental results indicated that •OH and •O2- were the decisive species for the dye degradation. The samples also exhibited outstanding photocatalytic water splitting for H2 evolution, and the high efficiency (306.36 μmol·cm−2·h−1) and stability were confirmed. The excellent photocatalytic performances of the Bi2Sn2O7/TiO2 NTAs photoelectrodes showed extensive potential applications in environmental pollution and green resource exploitation.