Heterostructured Nanoparticles Research Articles

Sol-Gel Combustion-Assisted Electrostatic Spray Deposition for Durable Solid Oxide Fuel Cell Cathodes.

The chemical instability of perovskite oxides containing Sr is a critical issue for the long-term operation of solid oxide fuel cells. In this study, we demonstrate a remarkable improvement in the chemical and electrochemical stability of a heterostructured La0.6Sr0.4CoO3-δ (LSC)-Ce0.9Gd0.1O1.95 (GDC) electrode. Electrostatic spray deposition was employed to fabricate heterostructured nanoparticles in a single step with a coaxial nozzle supplying the LSC powders in the core nozzle and the GDC precursors in the shell nozzle. Moreover, the reducing fuel added to the GDC precursor solution induced the sol-gel combustion reaction in the droplet to form a uniform nanocrystalline GDC coating with high surface coverage. The high surface coverage of GDC on the LSC more significantly improved long-term stability compared with than of the bare LSC cathode at a constant current density of 1 A/cm2 at 600°C for 100 h.

Injectable Hydrogel Based on Defect-Rich Multi-Nanozymes for Diabetic Wound Healing via an Oxygen Self-Supplying Cascade Reaction.

Diabetic wound healing remains challenging owing to the risk for bacterial infection, hypoxia, excessive glucose levels, and oxidative stress. Glucose-activated cascade reactions can consume glucose and eradicate bacteria, avoiding the direct use of hydrogen peroxide (H2 O2 ) and wound pH restriction on peroxidase-like activity. However, the anoxic microenvironment in diabetic wounds impedes the cascade reaction due to the oxygen (O2 ) dependence of glucose oxidation. Herein, defect-rich molybdenum disulfide nanosheets loaded with bovine serum albumin-modified gold nanoparticle (MoS2 @Au@BSA NSs) heterostructures are designed and anchored onto injectable hydrogels to promote diabetic wound healing through an O2 self-supplying cascade reaction. BSA decoration decreases the particle size of Au, increasing the activity of multiple enzymes. Glucose oxidase-like Au catalyzes the oxidation of glucose into gluconic acid and H2 O2 , which is transformed into a hydroxyl radical (•OH) catalyzed by peroxidase-like MoS2 @Au@BSA to eradicate bacteria. When the wound pH reaches an alkalescent condition, MoS2 @Au@BSA mimicks superoxide dismutase to transform superoxide anions into O2 and H2 O2 , and decomposes endogenous and exogenous H2 O2 into O2 via catalase-like mechanisms, reducing oxidative stress, alleviating hypoxia, and facilitating glucose oxidation. The MoS2 @Au@BSA nanozyme-anchored injectable hydrogel, composed of oxidized dextran and glycol chitosan crosslinked through a Schiff base, significantly accelerates diabetic wound healing.

Particle trapping, size-filtering, and focusing in the nonthermal plasma synthesis of sub-10 nanometer particles

Low-pressure nonthermal flowing plasmas are widely used for the gas-phase synthesis of nanoparticles and quantum dots of materials that are difficult or impractical to synthesize using other techniques. To date, the impact of temporary electrostatic particle trapping in these plasmas has not been recognized, a process that may be leveraged to control particle properties. Here, we present experimental and computational evidence that, during their growth in the plasma, sub-10 nm silicon particles become temporarily confined in an electrostatic trap in radio-frequency excited plasmas until they grow to a size at which the increasing drag force imparted by the flowing gas entrains the particles, carrying them out of the trap. We demonstrate that this trapping enables the size filtering of the synthesized particles, leading to highly monodisperse particle sizes, as well as the electrostatic focusing of the particles onto the reactor centerline. Understanding of the mechanisms and utilization of such particle trapping will enable the design of plasma processes with improved size control and the ability to grow heterostructured nanoparticles.

Morphology of ZnO nanorods and Au–ZnO heterostructures on different seed layers and their influence on the optical behavior

Zinc oxide nanorods were synthesized by low cost and low temperature chemical synthesis path by taking both ZnO and metal as the seed layer on the silicon substrate. The morphological study depicts seed layer as one of the key parameter in the growth process. ZnO NR/Au nanoparticles heterostructures were also fabricated. The enhancement of the visible emissions of the ZnO nanostructures is seen after the incorporation of gold nanoparticles at the surface. The visible (defect) emission corresponds to the yellow emission caused by oxygen interstitials. Luminescence vary considerably with position on the nanorod. The optical band gap obtained for Au–ZnO heterostructure to be 2.63 eV, which is lower than that of ZnO NRs. This changing trend of optical band gap for prepared Au/ZnO sample originated from the variety of defects. Tuning of the band gap energy of such wide band gap semiconductor is highly important for room temperature optical devices.

Carrier localization in zero-dimensional and one-dimensional CdSe-CdS heterostructures.

Mobile charge carriers in heterostructured nanoparticles are relevant for applications requiring charge separation and extraction. We investigate the benchmark systems CdSe-CdS core-shell quantum dots and quantum dots in quantum rods by optical and THz pump-probe spectroscopy. We relate photoconductivity and carrier location and observe that only shell-located electrons in quantum rods contribute to an observable photoconductivity. Despite the shallow electron confinement in the quasi-type II heterostructures, core-located carriers are bound into immobile excitons that respond on external electrical fields by polarization.

Design of hydrangea-type Co/Mo bimetal MOFs and MOF-derived Co/Mo2C embedded carbon composites for highly efficient oxygen evolution reaction

Transition metal organic framework (MOF)-derived catalysts are considered as promising electrocatalysts for the oxygen evolution reactions (OER) owing to their large surface area and abundant catalytic sites. However, to overcome the remaining limitations of their catalytic performance, it is imperative to develop catalysts with more efficient structure and sufficient intrinsic activity. Herein, we report a creative strategy for preparing efficient OER catalysts based on the Co/Mo MOFs with a two-dimensional (2D) hydrangea-type structure by employing molecular binders. In addition, these MOFs were successfully converted into hydrangea-type 2D Co/Mo2C heterostructure nanoparticles embedded in a N-doped carbon composite (H-2D Co/Mo2C@NC). Remarkably, H-2D Co/Mo2C@NC exhibited excellent OER performance with a low overpotential of 256 mV@η10 and a low Tafel slope of 48 mVdec−1. This can be attributed to the large accessible surface area of the nanoparticles owing to their hydrangea-type structure with open active sites and the modulation of the electronic structure of Co by Mo2C. This strategy will provide useful insights into the design of MOF-derived bimetal catalyst and heterojunction catalysts.

High-capacity and ultrastable lithium storage in SnSe2-SnO2@NC microbelts enabled by heterostructures.

The ingenious design of high-performance tin-based lithium-ion batteries (LIBs) is challenging due to their poor conductivity and drastic volume change during continuous lithiation/delithiation cycles. Herein, we present a strategy to confine heterostructured SnSe2-SnO2 nanoparticles into macroscopic nitrogen-doped carbon microbelts (SnSe2-SnO2@NC) as anode materials for LIBs. The composites exhibit an excellent specific capacity of 436.3 mA h g-1 even at 20 A g-1 and an ultrastable specific capacity of 632.7 mA h g-1 after 2800 cycles at 5 A g-1. Density Functional Theory (DFT) calculations reveal that metallic SnSe2-SnO2 heterostructures endow the lithium atoms at the interface with high adsorption energy, which promotes the anchoring of Li atoms, and enhances the electrical conductivity of the anode materials. This demonstrates the superior Li+ storage performance of the SnSe2-SnO2@NC microbelts as anode materials.

A New Nanoparticle Heterostructure Strategy with Highly Tunable Morphology Via Sequential Infiltration Synthesis

A New Nanoparticle Heterostructure Strategy with Highly Tunable Morphology Via Sequential Infiltration Synthesis

The effect of NiO-Ni3N interfaces in in-situ formed heterostructure ultrafine nanoparticles on enhanced polysulfide regulation in lithium-sulfur batteries

Inhibiting the “shuttle effect” of soluble polysulfides and improving reaction kinetics are the key factors necessary for further exploration of high-performance Li-S batteries. Herein, an effective interface engineering strategy is reported, wherein nitriding of an Ni-based precursor is controlled to enhance Li-S cell regulation. The resulting in-situ formed NiO-Ni3N heterostructure interface not only has a stronger polysulfide adsorption effect than that of monomeric NiO or Ni3N but also has a faster Li ion diffusion ability than a simple physical mixture. More importantly, this approach couples the respective advantages of NiO and Ni3N to reduce polarization and facilitate electron transfer during polysulfide reactions and synergistically catalyze polysulfide conversion. In addition, ultrafine nanoparticles are thought to effectively improve the use of additive materials. In summary, Li-S batteries based on this NiO-Ni3N heterostructure have the features of long cycle stability, rapid charging-discharging, and good performance under high sulfur loading.

Interface Dynamics in Ag-Cu3P Nanoparticle Heterostructures.

Earth-abundant transition metal phosphides are promising materials for energy-related applications. Specifically, copper(I) phosphide is such a material and shows excellent photocatalytic activity. Currently, there are substantial research efforts to synthesize well-defined metal–semiconductor nanoparticle heterostructures to enhance the photocatalytic performance by an efficient separation of charge carriers. The involved crystal facets and heterointerfaces have a major impact on the efficiency of a heterostructured photocatalyst, which points out the importance of synthesizing potential photocatalysts in a controlled manner and characterizing their structural and morphological properties in detail. In this study, we investigated the interface dynamics occurring around the synthesis of Ag–Cu3P nanoparticle heterostructures by a chemical reaction between Ag–Cu nanoparticle heterostructures and phosphine in an environmental transmission electron microscope. The major product of the Cu–Cu3P phase transformation using Ag–Cu nanoparticle heterostructures with a defined interface as a template preserved the initially present Ag{111} facet of the heterointerface. After the complete transformation, corner truncation of the faceted Cu3P phase led to a physical transformation of the nanoparticle heterostructure. In some cases, the structural rearrangement toward an energetically more favorable heterointerface has been observed and analyzed in detail at the atomic level. The herein-reported results will help better understand dynamic processes in Ag–Cu3P nanoparticle heterostructures and enable facet-engineered surface and heterointerface design to tailor their physical properties.

WO₃ Nanosheets/FeCo₂O₄ Nanoparticles Heterostructures for Highly Sensitive and Selective Ammonia Sensors

The gas - sensitive properties of metal oxide nanocomposites mainly depend on their structure and composition. In this paper, a highly sensitive ammonia sensor based on FeCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> nanoparticles modified WO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> nanosheet nanocomposite is prepared. The structure and composition of the sensor material are characterized by the systematic spectral and structural characterization. The results show that FeCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> nanoparticles grow on the surface of WO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> nanosheet and the interfacial contact is close, which leads to the P-N heterojunction and the increase of the relative specific surface area. The gas sensitivity test results show that the WO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> /FeCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> gas sensor has the highest sensitivity to NH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> (33.5 at 100 ppm) at 300 °C, with the characteristics of satisfactory selectivity, short response/recovery time, high repeatability and long stability. Compared with the intrinsic properties of WO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> and FeCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> , the sensitivity of WO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> /FeCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> nanocomposites is improved by tens of times. These excellent properties are attributed to the P-N heterojunction between WO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> nanosheets and FeCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> nanoparticles, as well as the good catalytic activity of FeCo <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> , which make it become a practical gas sensitive material for ammonia detection.

Heterostructures Made of Upconversion Nanoparticles and Metal-Organic Frameworks for Biomedical Applications.

Heterostructure nanoparticles (NPs), constructed by two single‐component NPs with distinct nature and multifunctional properties, have attracted intensive interest in the past few years. Among them, heterostructures made of upconversion NPs (UCNPs) and metal–organic frameworks (MOFs) can not only integrate the advantageous characteristics (e.g., porosity, structural regularity) of MOFs with unique upconverted optical features of UCNPs, but also induce cooperative properties not observed either for single component due to their special optical or electronic communications. Recently, diverse UCNP‐MOF heterostructures are designed and synthesized via different strategies and have demonstrated appealing potential for applications in biosensing and imaging, drug delivery, and photodynamic therapy (PDT). In this review, the synthesis strategies of UCNP‐MOF heterostructures are first summarized, then the authors focus mainly on discussion of their biomedical applications, particularly as PDT agents for cancer treatment. Finally, the authors briefly outlook the current challenges and future perspectives of UCNP‐MOF hybrid nanocomposites. The authors believe that this review will provide comprehensive understanding and inspirations toward recent advances of UCNP‐MOF heterostructures.

Fabrication of La2O3/g-C3N4 Heterojunction with Enhanced Photocatalytic Performance of Tetracycline Hydrochloride

In this study, La2O3/g-C3N4 heterojunction photocatalysts doped with different dosages of La2O3 were constructed by a facile ultrasound-assisted calcination approach. The as-prepared photocatalysts were characterized by XRD, FTIR, FESEM, TEM, XPS, PL and DRS to verify the composite photocatalysts’ purity and to investigate their structural, morphological and elemental composition, and their energy band. According to the results, a type of pure rod–sheet-shaped, heterostructured nanoparticle was successfully obtained. Decorated with 10% La2O3, 2 g/L of the composite sample had a 93% degradation rate for 20 mg/L tetracycline hydrochloride within 2 h under visible light at a pH of 7. After four successive photocatalytic runs, satisfactory stability and reusability was exhibited, with 70% of the tetracycline hydrochloride being removed in the final experiment. Electrons (e−), photogenerated holes (h+), superoxide radical anions (·O2−) and hydroxyl radicals (·OH) were the fundamental active species during the photocatalytic process and were investigated via quenching experiments. Furthermore, possible photocatalytic mechanisms were analyzed in this work.

Nickel and manganese oxide heterostructure nanoparticles supported by carbon nanotube for highly efficient oxygen evolution reaction catalysis

Heterostructures have been shown to play a key role in promoting electrocatalysis. However, it is still a challenge to design and prepare multi metals heterostructure catalyst with high performance. In this paper, a simple and efficient preparation method was used to anchor Nix|Mn1-xO heterostructure nanoparticles on CNTs with oxygen defect sites. The treated CNT were used to provide stable anchor sites for metal ions, and effectively induced the production of highly fused Nix|Mn1-xO nanoparticles with atomic-level heterogeneous interfaces. The Ni0.95|Mn0.05O/CNT catalyst shows a nice oxygen evolution reaction performance. At a current density of 10 mA cm−2, the overpotential is only 293 mV, and the Tafel slope is 55.6 mV dec-1, which is much better than that of Ni/CNT and MnO/CNT catalyst under the same conditions. According to the experimental result and density functional theory calculation, it is suggested that the proportion of heterogeneous metal elements, the phase composition at the heterogeneous interface, the heterostructure size and the heterostructure carrier will affect the oxygen evolution catalyst performance. This work is benefit for the design of cheap and high-performance catalyst with multi metal heterogeneous interfaces.

Ni@Ni3N Embedded on Three-Dimensional Carbon Nanosheets for High-Performance Lithium/Sodium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries are recognized as one of the most promising next-generation energy storage devices, but their practical application is greatly limited by several obstacles, such as the highly insulating nature and sluggish redox kinetics of sulfur and the dissolution of lithium polysulfides. Herein, three-dimensional carbon nanosheet frameworks anchored with Ni@Ni3N heterostructure nanoparticles (denoted Ni@Ni3N/CNS) are designed and fabricated by a chemical blowing and thermal nitridation strategy. It is demonstrated that the Ni@Ni3N heterostructure can effectively accelerate polysulfide conversion and promote the chemical trapping of polysulfides. Meanwhile, the carbon nanosheet frameworks of Ni@Ni3N/CNS establish a highly conductive network for fast electron transportation. The cells with Ni@Ni3N heterostructures as the catalyst in the cathode show excellent electrochemical performance, revealing stable cycling over 600 cycles with a low-capacity fading rate of 0.04% per cycle at 0.5 C and high-rate capability (594 mAh g-1 at 3 C). Furthermore, Ni@Ni3N/CNS can also work well in room-temperature sodium-sulfur (RT-Na/S) batteries, delivering a high specific capacity (454 mAh g-1 after 400 cycles at 0.5 C). This work provides a rational way to prepare the metal-metal nitride heterostructures to enhance the performance both of Li-S and RT-Na/S batteries.

Synthesis and Characterization of WO3/CeO2 Heterostructured Nanoparticles for Photodegradation of Indigo Carmine Dye.

WO3/CeO2 heterostructured nanocomposites containing different WO3 ratios (0.1, 0.3, 0.5, and 1.0 wt %) were synthesized by a precipitation method. The coupling of CeO2 and WO3 with a high specific surface area noticeably enhanced the photocatalytic activity of indigo carmine (IC) degradation under visible-light irradiation. The degradation rate constants (k) of 0.5 wt % WO3/CeO2 nanocomposites reached 4 and 5 times higher than those of CeO2 and WO3, respectively. Regarding the experimental results, the X-ray diffraction (XRD) patterns of the CeO2 spherical nanoparticles and rod-shaped WO3 were assigned to the cubic fluorite and orthorhombic phase structures, respectively. The increasing photocatalytic activity of nanocomposite samples could be attributed to the heterojunction of the photocatalysts with efficient charge separation and strong oxidative ability, which were confirmed by the photoluminescence spectra and diffuse reflectance spectrometry. The staggered heterojunction of the nanocomposite promoted efficient electron transfer and suppressed the recombination of photogenerated electrons and holes during the process.

Enhanced photocatalytic activity of cobalt-doped titanate nanotube heterostructures decorated with Cu2O-CuO nanoparticles for organic pollutant degradation under UV and visible irradiation

In this work, Co-doped titanate nanotubes decorated with Cu2O/CuO nanoparticle heterostructures (TNTs-Co-Cu) were successfully synthesized by hydrothermal method followed by an impregnation method. The photocatalysts were characterized by TEM, XRD, Raman spectroscopy, XPS, N2 adsorption/desorption, DRS, and Photoluminescence. The results confirm the success of the TNTs-Co-Cu heterojunctions synthesis and the excellent absorption exhibited in the visible light region. Furthermore, the photocatalytic activity of the TNTs-Co-Cu materials was higher than that of pure titanate nanotubes (TNTs) and doped with cobalt (TNTs-Co) for Methyl Blue (MB) photodegradation under UV and visible light irradiation. The improved photocatalytic activity may can explained due to the increased the lifetime of photogenerated electron/hole pairs. The photocatalytic mechanism study suggested that the photogenerated electrons in conduction band (CB) of the Cu2O flow through the CuO CB to CB of TNTs-Co, whereas the photogenerated holes migrate in the opposite direction. These transfers result in the production of O2– and OH radicals to promote the photooxidation reaction of MB. This study provides the understanding on the heterojunction mechanism of the MB photodegradation by TNTs-Co-Cu under UV irradiation and shows their high photocatalytic activity after 5 cycles, which make the TNTs-Co-Cu a promising photocatalyst for the multifunctional heterogeneous photocatalysis applications.

Lowering the voltage-hysteresis of CuS anode for Li-ion batteries via constructing heterostructure

Conversion-reaction anode materials always deliver high capacities when used for Li-ion batteries (LIBs). However, the large voltage-hysteresis between the discharge and charge potentials slide down the round-trip efficiency of the electrodes, which restricts their further application on commercial LIBs. Herein, an assumption that lowering the voltage-hysteresis by constructing heterostructure is proposed and further verified by CuS based electrode. As a proof of concept, CuS/MnS heterostructure nanoparticles confined by carbon layers are designed and further crosslinked into a 3D network, constructing CuS/MnS-C heterostructure nanofibers (HNFs). The as-formed heterointerfaces facilitate the charge separation and transfer, and further improve the kinetics. Meanwhile, the confinement and conductive network of the carbon nanofibers improve the structural stability and conductivity of the hybrid electrode. As a result, the voltage-hysteresis values of the CuS anode are lowered to 0.30 and 0.35 V in the well-designed CuS/MnS-C HNFs electrode, much smaller than the original values (0.82 and 0.70 V) in the CuS-C NFs electrode. Moreover, the CuS/MnS-C HNFs electrode exhibits the best excellent rate capability among their counterpart electrodes (493.5 mAh g−1 at 2.0 A g−1 with the coulombic efficiency of about 100%). This work would shed light on the development of practical conversion-reaction anode materials with low voltage-hysteresis.

Constructing defect-rich Ni9S8/Fe5Ni4S8 heterostructure nanoparticles for efficient oxygen evolution reaction and overall water splitting

Designing electrocatalysts from the perspective of modulating electronic structure and morphology has received considerable research interest in enhancing the electrocatalytic performance for oxygen evolution reaction (OER). In this work, nickel–iron based sulfides were synthesized through a one-pot hydrothermal approach which is characterized as defect-rich Ni9S8/Fe5Ni4S8 heterostructured nanoparticles. The presence of two phases, numerous defects, and uniformly distributed nanoparticles with the porous structure are conducive to modulating electronic structure, facilitating electron and mass transport, allowing the effective accessibility of active sites. The as-prepared Ni9S8/Fe5Ni4S8 exhibits enhanced electrocatalytic OER activity and long-lasting stability, which needs an overpotential of 239 mV for yielding 10 mA cm−2 and long-term stability better than RuO2. Furthermore, when employed in a two-electrode overall water splitting system, the catalyst coupled with Pt/C configuration exhibits comparable electrocatalytic performance to Pt/C and RuO2 based electrolyzer. This work not only offers a highly efficient and promising candidate catalyst for electrocatalytic water oxidation but also provides a simple synthesis method to heterostructured nanoparticles for other energy-related applications.

Construction of Smart Nanotheranostic Platform Bi-Ag@PVP: Multimodal CT/PA Imaging-Guided PDT/PTT for Cancer Therapy.

High-efficiency nanotheranostic agents with multimodal imaging guidance have attracted considerable interest in the field of cancer therapy. Herein, novel silver-decorated bismuth-based heterostructured polyvinyl pyrrolidone nanoparticles (NPs) with good biocompatibility (Bi-Ag@PVP NPs) were synthesized for accurate theranostic treatment, which can integrate computed tomography (CT)/photoacoustic (PA) imaging and photodynamic therapy/photothermal therapy (PDT/PTT) into one platform. The Bi-Ag@PVP NPs can enhance light absorption and achieve a better photothermal effect than bismuth NPs. Moreover, after irradiation under an 808 nm laser, the Bi-Ag@PVP NPs can efficiently induce the generation of reactive oxygen species (ROS), thereby synergizing PDT/PTT to exert an efficient tumor ablation effect both in vitro and in vivo. Furthermore, Bi-Ag@PVP NPs can also be employed to perform enhanced CT/PA imaging because of their high X-ray absorption attenuation and enhanced photothermal conversion. Thus, they can be utilized as a highly effective CT/PA imaging-guided nanotheranostic agent. In addition, an excellent antibacterial effect was achieved. After irradiation under an 808 nm laser, the Bi-Ag@PVP NPs can destroy the integrity of Escherichia coli, thereby inhibiting E. coli growth, which can minimize the risk of infection during cancer therapy. In conclusion, our study provides a novel nanotheranostic platform that can achieve CT/PA-guided PDT/PTT synergistic therapy and have potential antibacterial properties. Thus, this work provides an effective strategy for further broad clinical application prospects.