Heterostructure Nanocomposites Research Articles

Formation of Mn4Si7/Si(111), CrSi2/Si(111), and CoSi2/Si(111) Thin Film and Evaluation of Their Optically Direct and Indirect Band Gap

Now, silicon-based heterostructured nanocomposites are of great interest. Despite the fact that silicon semiconductor films (crystalline, polycrystalline, amorphous) have been systematically studied for a long time, heterostructural films are new materials, the study of which began relatively recently. We will produce and investigate the properties of heterostructured Mn4Si7/Si(111), CrSi2/Si(111), and CoSi2/Si(111) thin films using infrared and ultraviolet spectroscopies. Absorption, transmission, and diffuse reflectance spectra are obtained applying FTIR spectroscopy instruments and a UV spectrophotometer. The band gap energies calculated from the transmission spectra are in the interval 0.32–1.31 eV for films deposited on the silicon substrates and in the interval 0.36–1.25 eV for the glass substrates.

Facile synthesis of NiMn2O4/ZnMn2O4 heterostructure nanocomposite for visible-light-driven degradation of methylene blue dye

Nowadays, waste discharge and contaminants in drinking water have emerged as a significant global problem. Therefore, it is necessary to remove these pollutants from the water and photocatalysis is the best technique for this purpose. The co-precipitation technique was employed to produce NiMn2O4 and ZnMn2O4 and a photocatalyst containing NiMn2O4/ZnMn2O4 heterostructure nanocomposite. Various analytical techniques have been ascribed to examine the physical, morphological and optical features of the fabricated catalysts. XRD diffraction peak patterns were utilized to confirm the presence of cubic NiMn2O4, tetragonal ZnMn2O4 and NiMn2O4/ZnMn2O4 phases in a nanocomposite. In photodegradation tests, the nanocomposite catalyst outperformed the individual catalysts. After 60 minutes of visible light exposure, this nanocomposite catalyst eliminated the methylene blue (MB) dye, attaining substantially higher degradation rates than pure NiMn2O4 (66%) and ZnMn2O4 (77%). The nanocomposite catalyst was highly effective against methylene blue (MB) dye with a degradation efficiency of 92%.

Enhanced charge carriers separation/transportation via S-scheme ZnCeS–ZnWO heterostructure nanocomposite for photodegradation of synthetic dyes under sunlight

Domestic wastage and liquid discharge from industries cause serious water pollution and severely damage the life cycle of living species. Therefore, it is necessary to construct efficient photocatalysts for the removal of toxic pollutants from water. Herein, a novel heterostructure ZnWO–ZnCeS nanocomposite was prepared by the sol-gel route and studied its physical and photocatalytic properties using various analytical techniques. Under sunlight irradiation, the ZnWO–ZnCeS photocatalyst eliminated 99.7, 99.1, 99.0 % rhodamine-B (RhB), methylene blue (MB), and safranin-O (SO) dyes within 70 min with excellent performance higher than individual ZnWO and ZnCeS catalysts. The optimization tests exhibit the catalyst loading = 30 mg, dye content = 25 ppm, solution pH = 8 of ZnWO–ZnCeS against MB dye for practical application. The heterojunction of coupled ZnWO and ZnCeS leads to a synergistic effect that facilitates the charge transport and hampers the recombination of photo-induced charge carriers thereby leading to boosted photocatalytic performance. Furthermore, based on the scavenging test, the hydroxyl and superoxide radicals were the reactive species during the photodegradation reaction. The designed photodegradation reaction mechanism has proposed the formation of an S-scheme in ZnWO–ZnCeS that led to the accumulation of electrons at ZnCeS and holes at ZnWO, favoring the formation of reactive species for dye degradation. Moreover, this work provides a novel direction to synthesize S-scheme heterostructure photocatalysts for application in wastewater treatment.

Recent Advances in Efficient Photocatalytic Degradation Approaches for Azo Dyes

In recent decades, the textile industry has contributed to continuous pollution in the environment. Synthetic dyes which are commonly found in waste water are azo, sulfur, anthraquinone, triphenylmethyl, indigoid, and phthalocyanine derivatives. These pollutants block the light penetration in water bodies and prevent photosynthesis activity, thereby affecting aquatic life. As an environmental crisis, several technologies have been explored to control pollution. Among all the techniques, the photocatalysis process is considered as a green, simple, and economical process. To improve the photocatalytic activity, researchers worldwide have investigated various photocatalysts such as metal oxides, metal ferrites, and heterostructured nanocomposites. The major goal of this review article is to propose a high-performing, cost-effective hybrid photocatalyst reported to date for prospective azo dye pollutant remediation. This review article also aimed to highlight the challenges and uncertainties associated with dye degradation in the photocatalytic process.

High discharge energy density in rationally designed graphene oxide@zinc oxide/polymer blend-polyetherimide heterostructured bilayer nanocomposites

The advancement of new dielectric materials exhibiting greater discharge energy density is crucial for current power systems and electronic devices. In this work, various weight percentages of graphene oxide@zinc oxide (GO@ZO) nanofillers were incorporated inside a polymer blend of poly(vinylidene fluoride-hexafluoropropylene)/polyetherimide (P(VDF-HFP)/PEI; shortened as BP) and used as a high dielectric top layer. In contrast, linear-type PEI (L) was used as a bottom insulation layer to achieve a high breakdown strength (Eb) in bilayer nanocomposites. As a result, the 2BP-L composite demonstrated a high discharged energy density of 12.63 J/cm3 at an electric field of 527 MV/m with only 2 wt% GO@ZO nanofillers addition in the top layer. Such a high discharge energy density with minimal nanofiller loading is attributed to the utilization of novel surface-decorated GO@ZO nanofillers and new bilayer-heterostructured linear/ferroelectric-linear polymer. In comparison to its counterparts (i.e., PEI, P(VDF-HFP) and 0BP-L), the 2BP-L nanocomposite showed ∼426.3 %, 92.5 %, and 9.8 % enhancement in discharge energy density, respectively. The discharge rate and stability analysis revealed a significantly higher power density of 0.55 MW/cm3, indicating its high potential to be used as a pulsed power system. Finite element simulation revealed that the effective internal electric field distribution and higher dielectric displacement in 2BP-L resulted in such enhancement over its counterparts. This study presents a new model to maximize the energy storage capability of flexible energy storage devices and advances knowledge of the polarization mechanisms and breakdown of bilayer nanocomposite dielectric materials.

Near-Infrared-II-Activatable Self-Assembled Manganese Porphyrin-Gold Heterostructures for Photoacoustic Imaging-Guided Sonodynamic-Augmented Photothermal/Photodynamic Therapy.

Porphyrins and their derivatives are widely used as photosensitizers and sonosensitizers in tumor treatment. Nevertheless, their poor water solubility and low chemical stability reduce their singlet oxygen (1O2) yield and, consequently, their photodynamic therapy (PDT) and sonodynamic therapy (SDT) efficiency. Although strategies for porphyrin molecule assembly have been developed to augment 1O2 generation, there is scope for further improving PDT and SDT efficiencies. Herein, we synthesized ordered manganese porphyrin (SM) nanoparticles with well-defined self-assembled metalloporphyrin networks that enabled efficient energy transfer for enhanced photocatalytic and sonocatalytic activity in 1O2 production. Subsequently, Au nanoparticles were grown in situ on the SM surface by anchoring the terminal alkynyl of porphyrin to form plasmonic SMA heterostructures, which showed the excellent near-infrared-II (NIR-II) region absorption and photothermal properties, and facilitated electron-hole pair separation and transfer. With the modification of hyaluronic acid (HA), SMAH heterostructure nanocomposites exhibited good water solubility and were actively targeted to cancer cells. Under NIR-II light and ultrasound (US) irradiation, the SMAH generates hyperthermia, and a large amount of 1O2, inducing cancer cell damage. Both in vitro and in vivo studies confirmed that the SMAH nanocomposites effectively suppressed tumor growth by decreasing GSH levels in SDT-augmented PDT/PTT. Moreover, by utilizing the strong absorption in the NIR-II window, SMAH nanocomposites can achieve NIR-II photoacoustic imaging-guided combined cancer treatment. This work provides a paradigm for enhancing the 1O2 yield of metalloporphyrins to improve the synergistic therapeutic effect of SDT/PDT/PTT.

Optimizing Gas Sensing Properties of Fe-Loaded Indium Zinc Oxide Nanocomposite for Efficient Detection of Ammonia Gas

The current study delineates the role of gas sensing properties of Fe-IZO (Iron loaded Indium Zinc oxide) a mixed metal oxide nanocomposite. The heterostructured Fe-IZO nanocomposite (NC) was synthesized via the facile co-precipitation method. The Fe-IZO NC was characterized by various experimental techniques and the results attained allowed us to suggest the mechanism for considering the connection between morphological variations and gas-sensing characteristics of Fe-IZO NC. One of the cutting-edge circumstances now-a-days is the prime use of gas sensors for environmental applications. The NC has a good selectivity for NH3 gas that has shown good stability up to 80 d. The response time (ℸres) is 64 s, recovery time (ℸrec) is 72 s for 50 ppm (parts per million) and obtained a highest response of 87% at room temperature. The Fe-IZO NC heterostructure with efficient charge transfer can enable the subsequent reaction mechanism with NH3 gas and the adsorbed oxygen ions leading to an increased response. Consequently, the results attained in this work has shown that the synthesized heterostructured NC sensor is suitable for room temperature NH3 sensing with high performance.

Synthesis of heterostructured nanocomposites as supercapacitor electrodes and investigation of their electrochemical properties

Synthesis of heterostructured nanocomposites as supercapacitor electrodes and investigation of their electrochemical properties

Design of rich defects carbon coated MnFe2O4/LaMnO3/LaFeO3 heterostructure nanocomposites for broadband electromagnetic wave absorption

The precise construction of abundant heterointerfaces and defects in manganese ferrite for efficient electromagnetic wave (EMW) absorption is highly appealing, yet remains a grand challenge. Herein, we report a class of carbon-coated MnFe2O4/LaMnO3/LaFeO3 heterostructure nanocomposites with foam-like porous structures for enhancing EMW absorption. The optimized sample (the molar ratio of Mn:Fe:La is 1:2:1) delivers extraordinary absorption performance of the minimum reflection loss reaches −68.25 dB at 4.24 GHz, along with the maximum effective absorption (RL ≤ -10 dB) bandwidth is 12.26 GHz (3.11–15.37 GHz) at a thickness of 3.9 mm. EMW absorption mechanism reveals that the multiple polarizations induced by adjustable heterointerfaces and abundant defects in spinel/perovskite nanocomposites enhance its dielectric loss capacity, resulting in impressive EMW absorption performance. Moreover, the amorphous carbon shell further optimizes impedance matching. This study not only provides a good reference for future preparation of microwave absorbing materials with rich heterogeneous interfaces and defects but also broadens the application of such kinds of carbon-coated spinel/perovskite nanocomposites.

Facile synthesis of green engineered CuO/Cu2O-C nano heterostructures with the controlled Cu2O content for the photodegradation of crystal violet

Copper oxide/cuprous oxide and carbon heterostructured nanocomposites (CuO/Cu2O-C NCs) were fabricated using an agro-biomass wheatgrass extract (WGE), presenting an innovative, eco-friendly, and facile green synthetic approach. The CuO/Cu2O-C nanocomposites engineered using WGE were extensively characterized using UV–Vis, IR, XRD, DLS, XPS, SEM, TEM, BET, and TGA characterization techniques. The synthesized CuO/Cu2O-C NCs were crystalline with a monoclinic phase and an average crystallite size of 32 nm, as confirmed by XRD. Tauc plots were utilized to calculate the band gap energies (2.05 and 1.53 eV). The synthetic procedure is optimized, and the effect of plant extract in the controlled synthesis of Cu2O content in the CuO/Cu2O-C NCs was investigated. These green CuO/Cu2O-C NCs were tested for photocatalytic activity. A detailed kinetic study was conducted to degrade pathological effluent crystal violet (CV). The nanocomposite with a higher concentration of Cu2O is potentially a superior photocatalyst and demonstrated an excellent synergistic action, removing around 80 % of the crystal violet stain in visible light. Apart from photodegradation, these CuO/Cu2O-C NCs were good antioxidants and displayed good antibacterial activity against the gram-positive and gram-negative bacterial strains. The key highlight of this work is the low-cost disruptive engineering strategy for synthesizing frugal nanomaterials for multifaceted applications.

Efficient photodegradation of paraquat herbicide over TiO2-WO3 heterojunction embedded in diatomite matrix and process optimization.

Photodegradation of paraquat herbicide was assessed over several TiO2-WO3 heterojunctions embedded in the diatomite matrix. The characterization results indicated that WO3 embedding in the TiO2 decorated-diatomite matrix could not only enhance the adsorption capacity, visible-light response, and distribution of semiconductor species but also lessen the recombination rate and band gap energy. These characteristics were more noticeable as 5 wt.% of WO3 was embedded. Despite better optical properties of immobilized TiO2-WO3 nanocomposites, overloading WO3 generally alleviates the synergetic effect of tungsten due to surface coverage of diatomite matrix and, subsequently, the significant attenuation of textural properties, more formation of agglomerations and defects as trapping centers in the oxidation sites of heterostructures, and also, less likely of forming TiO2-WO3 heterojunction. In accordance with characterization results, the highest UV-photodegradation of paraquat was attained over heterostructured nanocomposite containing 5 wt.% WO3 (T25-W5/Di). The effects of significant operating parameters were also investigated, modeled, and optimized using response surface methodology (RSM)-central composite design (CCD). Under optimized operation conditions, the experimental removal efficiency of paraquat reached 97.1 and 80% using UV and simulated solar light, respectively. Moreover, the reusability results confirm the sustained activity of the T25-W5/Di nanocomposite.

Constructing novel inorganic-organic α-Fe2O3/SNW-1 Z-scheme heterojunction for Methylene Blue photodegradation

A novel organic/inorganic heterostructured photocatalyst binary nanocomposite was typically prepared by the solvothermal method. The overwhelming superiority of this composite has been confirmed by spectroscopic and characterization methods, where the addition of α-Fe2O3 reduced the agglomeration of the Schiff-based covalent organic framework SNW-1 and significantly increased the specific surface area. The effects of operating parameters such as catalyst dosage, initial solution concentration, and pH on photocatalytic degradation of methylene blue (MB) dye were carefully investigated. Among them, a UV irradiation time of 80 min, a powder dose of 0.6 g/L, and pH=2 were the best choice. Under these favorable conditions, the α-Fe2O3/SNW-1 system exhibited excellent photocatalytic performance, and the degradation rate of MB reached more than 95%. In addition, the photocatalytic degradation efficiency of the pollutants acid orange 7 (AO7), rhodamine-B (RhB), and acid red (ArB) comfortably reached 92%, 92%, and 91%, respectively. After five cycles of testing, the prepared photocatalyst showed good stability and reusability. Through energy band calculation, free radical quenching experiment, and electron paramagnetic resonance (ESR) study, it was discovered that the main active substances were ·O2- and ·OH, and the photogenerated holes and electrons also participated in the photocatalytic reaction. The Z-scheme charge transfer mechanism of α-Fe2O3/SNW-1 was proposed. Photoelectric chemical tests further demonstrated the extraordinary photocatalytic activity, low internal resistance, and high carrier separation capability of the binary nanocomposites. This study presents the potential application of high-performance photocatalysts for the removal of organic dyes in water purification.

PtS-decorated WS2 microflakes based sensors for selective ammonia detection at room temperature

In this paper, platinum sulfide decorated WS2 microflakes (PtS/WS2) heterostructure nanocomposites were prepared by an in-situ chemical reduction process. The chemiresistive-type gas sensor based on the synthesized PtS/WS2 heterostructure nanocomposites exhibited a significantly improved sensing properties compared to that of the pure WS2 microflakes at different concentration of NH3 from 1 ppm to 10 ppm at room temperature. As the concentrations of PtS nanoparticles decorated on the surface of WS2 microflakes increased, the response of the PtS/WS2 heterostructure sensor to ammonia firstly increased when the concentration of PtS increased up to 1 wt%, whereas above 1%, the response decreased instead. Moreover, it was found that the response speeds of the PtS-decorated WS2 were significantly improved compared to that pure WS2. The sensors also exhibited excellent selectivity to formaldehyde, toluene, acetone, methanol and ethanol at room temperature. The sensing mechanisms were studied by using the in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The enhanced sensing properties could be explained by “electronic sensitization” effect induced by the PtS/WS2 heterostructure, being confirmed by density functional theory (DFT) calculations.

Novel ZnO/CdO heterostructure for high efficiency formaldehyde sensing with high response and low detection limit at low temperature

ZnO/CdO heterostructure nanocomposites were synthesized using a simple stirring method at room temperature combined with subsequent calcination. The ZnO/CdO nanocomposites-based sensors displayed higher selectivity and higher response at lower optimal operation temperature to formaldehyde gas than pure ZnO and CdO. Especially, the sensor based on the ZnO/CdO prepared with 0.2 g CdSO4 (ZnO/CdO-3 sensor) showed a response value of 104 to 50 ppm HCHO at 150 °C, which is around 5.9 times that of the pristine ZnO sensor. In addition, the ZnO/CdO-3 sensor showed a low experimental detection limit of 100 ppb and relatively good humidity resistance. Moreover, the sensor can work at even lower working temperature with high response, for example, the response is 7.5 to 50 ppm HCHO at 90 °C. The doping of CdO and the synergistic effect of the n-n heterojunction at the interface are the main reasons contributing to the improvement of HCHO sensing property.

Novel PWO/ ZnO heterostructured nanocomposites: Synthesis, characterization, and photocatalytic performance

Photocatalytic degradation is becoming an increasingly attractive method for addressing environmental remediation challenges. In this work, the novel pure PWO/ZnO and doped PWO: Er/ZnO: Ag heterostructure nanocomposites with premier photocatalytic efficiency were synthesized via a simple co-precipitation method followed by a solvothermal procedure. X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX), and ultraviolet–visible (UV–Vis) absorbance measurements techniques were employed to characterize the structural and optical properties. HRTEM images prove the possibility of intimate contact formation at the pure and doped PWO/ZnO heterostructure nanocomposite interfaces. The photocatalytic performance of the PWO/ZnO heterostructure nanocomposites in the degradation of the methylene blue (MB) and methyl orange (MO) dyes under UVA light was evaluated. The photocatalysts’ ability in the mineralization of organic pollutants was confirmed by the TOC test. BET and zeta potential analyses were used to study the dye adsorption mechanisms. Additionally, adsorption isotherms and kinetics have been investigated to describe the adsorption of MB and MO into the samples. The degradation rates of MB with PWO/ZnO and PWO: Er/ZnO: Ag heterostructure nanocomposites were 4.7 and 6.6 times higher than those of PWO and PWO: Er nanoparticles. This rate for MO degradation is 5.2 and 3.5 times higher than that of pure PWO and PWO: Er nanoparticles, respectively. This study outlines an easy method to develop innovative, highly effective heterostructure nanocomposites capable of converting UVA light into photocatalytic performance.

Slippery Graphene-Bridging Liquid Metal Layered Heterostructure Nanocomposite for Stable High-Performance Electromagnetic Interference Shielding.

Gallium-based liquid metal (LM) with intriguing high electrical conductivity and room-temperature fluidity has attracted substantial attention for its potential application in flexible electromagnetic interference (EMI) shielding. However, the EMI shielding performance of the existing LM-based composites is unsatisfying due to the irreconcilable contradiction between high EMI shielding efficiency (SE) and low thickness. In addition, the research on environmentally stable EMI shielding material has become an urgent need due to the increasingly sophisticated application scenarios. Herein, we prepared a reduced graphene oxide (rGO) bridging LM layered heterostructure nanocomposite with the liquid-infused slippery surface (S-rGO/LM), which exhibits an ultrahigh X-band EMI SE of 80 dB at a mere internal thickness of 33 μm, and an extremely high value of 100 dB at an internal thickness of 67 μm. More significantly, protected by the ultrathin (2 μm) yet effective slippery surface, the S-rGO/LM film exhibits exceptional EMI shielding stability (EMI SE stays above 70 dB) after enduring various harsh conditions (harsh chemical environments, extreme operating temperatures, and severe mechanical wearing). Moreover, the S-rGO/LM film also demonstrates satisfying photothermal behavior and excellent Joule heating performance (surface temperature of 179 °C at 1.75 V, thermal response <10 s), which endows it with the capability of anti-icing/de-icing. This work proposes a way to construct an LM-based nanocomposite with reliable high-performance EMI shielding capability, which shows great potential for applications in wearable devices, defense, and aeronautics and astronautics.

Facile Hydrothermal Synthesis of Visible‐Light‐Driven MnS/rGO Nanocomposite for Photocatalytic Degradation of Methylene Blue Dye

Currently, the global problem of poisonous and nondegradable organic water pollutants cannot be ignored. Heterogeneous photocatalysis is an advanced oxidation process (AOP) that uses semiconducting materials as a catalyst to clean water. Nanosize semiconductor photocatalysts are well recognized for their practical and cost‐effective way of cleaning up environmental pollution when exposed to visible light. Herein, a simple hydrothermal approach is used to create an MnS/rGO nanocomposite for the degradation of aromatic dyes under visible light. Powder X‐ray diffraction, scanning electron microscopy, and UV–visible spectroscopy are utilized to analyze the synthesized photocatalyst. Methylene blue is investigated for photocatalytic degradation using the MnS/rGO heterostructure nanocomposite. Under visible light, the composite shows photocatalytic degradation efficiency of 91.8% owing to the addition of rGO, its synergistic effects, high specific surface area, and a decrease in photoinduced electron–hole pair recombination. The fabricated nanocomposite MnS/rGO with significantly better photoresponse activity is successfully protected from charge recombination by reduced graphene oxide, which functions as a superb electron‐carrying material.

Synergistic effect of oxygen vacancy defects and TiO2/WO3 heterostructures in photocatalytic hydrogen production and dye degradation

The exploration of cost-effective and efficient photocatalysts for environmental remediation and hydrogen production is a topic of immense importance in contemporary research. Titanium dioxide (TiO2) has been extensively researched in the area of environmental and energy photocatalysis due to its outstanding photocatalytic activity. However, its high photogenerated carrier recombination rate and wide bandgap limit the application. In this work, a TiO2/WO3 heterostructure nanocomposite with oxygen vacancy defects was synthesized through a simple sol-gel method. The introduction of oxygen vacancies reduced the bandgap and expanded the light absorption range, while the TiO2/WO3 heterostructure increased the photogenerated carriers and facilitated their separation. The resulting TiO2/WO3 nanocomposites exhibited enhanced photocatalytic activity, producing 101.88 μmol of hydrogen in 2 h for 100 mg of the nanocomposites, while the reaction constant for degrading dyes reached 0.1414 min−1. Moreover, the nanocomposites showed excellent stability under sunlight. This exploration provides a novel approach for designing and preparing TiO2-based composite photocatalysts.

Ultrafast photodegradation of textile industry dyes using efficient sulfide based ternary nanocomposites

We developed novel zinc-cadmium-bismuth sulfide (Zn–Cd–Bi2S3) and Zn–Cd–SnS nanocomposites to fabricate a heterojunction by an easy chemical technique to improve photocatalytic degradation of textile dye. Crystalline size and lattice parameter are analyzed using X-ray diffraction (XRD) spectrometer. The obtained strong diffraction peaks with various diffraction planes confirm the fabrication of a high crystal quality nanocomposite as well as the identification of its mixed crystal structure. The morphological information is studied using scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (TEM). Due to its higher surface energy, the as-prepared nanocomposite displayed agglomeration by adjoining to tiny particles. The roughness of surface is studied by atomic force microscopy (AFM). Fourier transform-infrared spectroscopy (FT-IR) used to study about presence of organic functional groups on the surface of nanocomposite. Using UV–Visible and photoluminescence spectra, the impact of shifting the positions of Sn and Bi ions on the optical characteristics is investigated. Thermal property of the nanocomposite is studied by thermogravimetric–differential thermal analysis (TG–DTA) at air atmosphere. We examine and compared the photocatalytic activity of Zn–Cd–Bi2S3 and Zn–Cd–SnS nanocomposites for the crystal violet (CV) dye. Under the sun light irradiation Zn–Cd–Bi2S3 nanocomposite demonstrated a highest percentage of degradation (88.5%) within a short period (120 min). The obtained photocatalytic results indicate that the active radicals •O2-, h+, and •OH- are favourable for the photocatalytic reaction. A possible photocatalytic mechanism for the dye degradation for the photocatalyst is proposed. Due to the narrow band gap, wide range of incident light captured by the heterostructure nanocomposite and the photogenerated electrons and holes is effectively separated in the Zn–Cd–Bi2S3.

Hierarchically Structured Nanotube Arrays as Heterogenous Photocatalysts for Highly Efficient Broadband Photoinduced Controlled Radical Polymerization

Highly ordered TiO2 nanotube arrays (TNTAs) and their heterostructure nanocomposites by structural engineering design were utilized as heterogeneous photocatalysts for highly efficient broadband photoinduced controlled radical polymerization (photoCRP), including photoATRP and PET-RAFT. Highly efficient broadband UV-visible light responsive photoCRP was achieved by combining the acceleration effects of electron transfer derived from the distinctive highly ordered nanotube structure of TNTAs and the localized surface plasmon resonance (LSPR) effect combined with the formation of the Schottky barrier via modification of Au nanoparticles. This polymerization system was capable to polymerize acrylate and methacrylate monomers with high conversion, "living" chain-ends, tightly regulated molecular weights, and outstanding temporal control properties. The heterogeneous nature of the photocatalysts enabled simple separation and effective reusability in subsequent polymerizations. These results highlight the modular design of highly efficient catalysts to optimize the controlled radical polymerization process.