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Harvesting solar energy to drive the semiconductor photocatalysis offers a promising tactic to address ever‐growing challenges of both energy shortage and environmental pollution. Design and synthesis of nano‐heterostructure photocatalysts with controllable components and morphologies are the key factors for achieving highly efficient photocatalytic processes. One‐dimensional (1D) semiconductor nanofibers produced by electrospinning possess a large ratio of length to diameter, high ratio of surface to volume, small grain sizes, and high porosity, which are ideally suited for photocatalytic reactions from the viewpoint of structure advantage. After the secondary treatment of these nanofibers through the solvothermal, gas reduction, in situ doping, or assembly methods, the multi‐component nanofibers with hierarchical nano‐heterostructures can be obtained to further enhance their light absorption and charge carrier separation during the photocatalytic processes. In recent years, the electrospun semiconductor‐based nano‐heterostructures have become a "hot topic" in the fields of photocatalytic energy conversion and environmental remediation. This review article summarizes the recent progress in electrospinning synthesis of various kinds of high‐performance semiconductor‐based nano‐heterostructure photocatalysts for H2 production, CO2 reduction, and decomposition of pollutants. The future perspectives of these materials are also discussed. [ABSTRACT FROM AUTHOR]

Mo-doped BiVO4 microcrystals with tetragonal structures were prepared by a hydrothermal method. The phase transformation from monoclinic to tetragonal was observed as the concentration of molybdenum ions increased up to 10 mol%. Accordingly, the morphology of the as-preparation samples evolved from plate-shaped (molybdenum-free BiVO4) to pie-like (BiVO4:Mo). The photocatalytic activity of BiVO4:Mo with a tetragonal structure was much higher than that of the pure BiVO4 host with a monoclinic phase by using RhB as the simulated pollutants under sun-like irradiation. The degradation rate of RhB was increased from 40% with molybdenum-free BiVO4 to 97.8% with the Mo-doped BiVO4 materials. [ABSTRACT FROM AUTHOR]

Plasmonic nanostructures have received significant attention in the field of solar-to-fuels conversion, because they can collect and utilize abundant low-energy photons to generate high-energy hot electrons for producing green chemical fuels. However, the ultrafast relaxation process of hot electron often leads to poor quantum yields of plasmonic nanostructures. Herein, we construct the one-dimensional W 18 O 49 /Carbon heterostructure for employing low-cost electrospun carbon fibers as the “electron mediator” to hinder the relaxation of hot electron in plasmonic W 18 O 49 nanowires. We confirm that the IR-excited plasmonic hot electrons in W 18 O 49 nanowires can quickly transfer to carbon fibers within only ∼50 fs in the W 18 O 49 /C heterostructure. This kinetics time is much shorter than the relaxation time of these hot electrons from high-energy surface plasmon (SP) to the ground state in W 18 O 49 nanowires (∼5.5 ps). As a result, upon low-energy IR-light excitation, the W 18 O 49 /C heterostructures exhibit nearly 2-fold enhancement on the catalytic H 2 production from ammonia borane as compared to single W 18 O 49 nanowires. Wavelength-dependent catalytic tests further indicate that this plasmon-enhanced catalytic activity is induced by the ultrafast transport process of plasmonic hot electron due to the localized surface plasmon resonance. [ABSTRACT FROM AUTHOR]

Rational arrangement of nanosized semiconductor components in the multi-heterojunction photocatalyst can lead to the formation of a high-speed transport channel for charge-carriers separation and migration, which provides a promising way to achieve excellent photocatalytic efficiency for solar fuels generation. Herein, we develop a photo-assisted self-optimization strategy to re-build the charge-carriers transport channel in the copper species nanocrystals/TiO 2 electrospun nanofibers with the organic hydrogen-carrier molecules as the photo-reactants. As a result of the dynamics difference of the excitons migration during the photocatalytic process, the binary CuO/TiO 2 heterojunction nanofibers are recrystallized to form the quaternary Cu/Cu 2 O/CuO/TiO 2 multi-heterojunction nanofibers that exhibits a higher rate constant ( ∼ 1.7 × 10 8 S − 1 ) for the interfacial electron-transfer than the former nanofibers ( ∼ 0.7 × 10 8 S − 1 ) due to the improved charge-carriers transport channel. In this way, a 40-fold enhanced H 2 generation rate was observed on the recrystallized nanofibers photocatalyst during the photocatalytic decomposition of formic acid as compared to the pure TiO 2 nanofibers. Our work presents an available paradigm to skillfully use a transient photo-physicochemical process to mildly engineer a high-quality charge-carriers transport channel in the hetero-nanophotocatalyst for realizing an optimal photocatalytic performance. [ABSTRACT FROM AUTHOR]

The photocatalytic activity of a semiconductor is heavily influenced by its photocatalytic cumulative effect on the four consecutive photo-physiochemical processes, including light harvesting, charge separation, charge migration, and charge utilization. Herein, we proposed and synthesized the well-designed plasmonic Au@Pt/CdS/C 3 N 4 heterostructure to enhance the photocatalytic cumulative effect by simultaneously sensitizing the total four processes. [Display omitted] • Pt/CdS-selective-coated Au nanocubes are assembled onto C 3 N 4 nanosheets. • Plasmon-enhanced photocatalytic cumulative effect on the Au@Pt/CdS/C 3 N 4 heterostructure. • Plasmon-induced HET, RET, and LEFE processes are achieved simultaneously. • Photocatalytic activities of H 2 generation and CO 2 reduction are remarkably enhanced. The photocatalytic activity of a semiconductor is heavily influenced by its photocatalytic cumulative effect on the four consecutive photo-physiochemical processes, including (I) light harvesting, (II) charge separation, (III) charge migration, and (IV) charge utilization. However, it is still a tremendous challenge to enhance the photocatalytic cumulative effect by simultaneously sensitizing the total above I-IV processes of the semiconductor. Herein, we synthesized the well-designed plasmonic Au@Pt/CdS/C 3 N 4 heterostructure through assembling Pt/CdS-selective-coated Au nanocubes onto the two dimensional (2D) ultrathin C 3 N 4 nanosheets (NSs). We have also demonstrated that selectively coating CdS nanoparticle-clusters (NPCs) and Pt nanoparticles (NPs) onto the surfaces and edges of Au NCs could boost the II and III processes of the formed Au@Pt/CdS NCs based on the resonance energy transfer (RET) and "hot electron" transfer (HET) behaviors, respectively, due to the localized surface plasmon resonance (LSPR) of Au NCs. The assembly of the Au@Pt/CdS NCs onto the C 3 N 4 NSs formed lots of 2D Au/CdS/C 3 N 4 interface, where the Au-LSPR not only boosted the I process at the "type II" heterojunction regions of CdS/C 3 N 4 , but also improved the II process of C 3 N 4 NSs via the local electromagnetic field enhancement (LEFE). Furthermore, the quasi-2D porous structure of CdS NPCs increased the surface active-sites at the 2D CdS/C 3 N 4 interface, therefore enhancing the IV process. As such, when normalizing the effective active area as the Au@Pt/CdS/C 3 N 4 hetero-interface region, the plasmonic heterostructure exhibited the ∼ 17.2-fold and ∼ 14.3-fold enhancements on the photocatalytic H 2 evolution and CO 2 reduction as compared to the CdS/C 3 N 4 heterojunction, respectively. [ABSTRACT FROM AUTHOR]

In this work, we present the 2D/2D type of heterojunction photocatalysts fabricated by horizontal loading ultrathin hexagonal SnS 2 nanosheets on g-C 3 N 4 nanosheets through a facile ultrasonic dispersion method. The sheet-like structures of these two nanomaterials induce a large contact region in the heterojunction interface, as evidenced by electron microscopic analyses. By taking advantage of this feature, the as-fabricated SnS 2 /g-C 3 N 4 heterojunction nanosheets exhibit considerable improvement on the photocatalytic activities for the degradation of organic dyes and phenols under visible light irradiation as compared to pure g-C 3 N 4 and SnS 2 nanosheets. In particular, the optimal heterojunction nanosheet with 5.0 wt.% SnS 2 shows the apparent rate constant of ∼0.2 min −1 for the RhB photodegradation, which is higher than that of pure g-C 3 N 4 and SnS 2 nanosheets by a factor of 4 and 8, respectively. Further studies by steady-state and transient photoluminescence spectroscopy indicate that the photosynergistic effect of SnS 2 /g-C 3 N 4 heterojunction can remarkably enhance the photoinduced interfacial charge transfer, thereby increasing the charge separation during the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

We present high-yield hydrogen production through selective photocatalytic decomposition of formic acid by using electrospun TiO 2 nanofibers decorated with AuPd bimetallic alloy nanoparticles under simulated sunlight irradiation. By using only 5 mg of the AuPd/TiO 2 nanofibers containing the 0.75% Au and 0.25% Pd, we could achieve an optimal H 2 generation rate of 88.5 μmol h −1 with an apparent quantum yield at 365 nm as 15.6%, which is higher than that of the Pd/TiO 2 and Au/TiO 2 nanofibers by a factor of 1.6 and 4.5, respectively. The enhanced photocatalytic decomposition of formic acid for H 2 generation could be attributed to the stronger electron-sink effect of AuPd alloy nanoparticles, the high selectivity of Pd for the dehydrogenation of formic acid, and the surface plasmon resonance effect of Au. More importantly, we demonstrate that the photocatalytic processes enable re-activation of the AuPd nanoparticles that were poisoned by CO during thermal decomposition of formic acid. As such, the presented AuPd/TiO 2 nanofibers are promising materials for re-generation of H 2 under mild conditions from liquid storage carrier of hydrogen. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) Pt/TiO 2 hybrid nanofibers (HNFs) with different concentrations of Pt were fabricated by a facile two-step synthesis route combining an electrospinning technique and calcination process. X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) results showed that the Pt nanoparticles (NPs) with the size of 5–10 nm were well dispersed in the TiO 2 nanofibers (NFs). Further investigations from the UV–Vis diffuse reflectance (DR) and X-ray photoelectron spectroscopy (XPS) analysis revealed that some Pt ions were incorporated into the TiO 2 lattice as Pt 4+ state, which contributed to the visible light absorption of TiO 2 NFs. Meanwhile, the Pt 2+ ions existing on the surface of Pt NPs resulted in the formation of Pt–O–Ti bond at Pt NPs/TiO 2 NFs interfaces that might serve as an effective channel for improving the charge transfer. The as-electrospun Pt/TiO 2 HNFs exhibited remarkable activities for photocatalytic H 2 evolution under visible light irradiation in the presence of l -ascorbic acid as the sacrificial agent. In particular, the optimal HNFs containing 1.0 at% Pt showed the H 2 evolution rate of 2.91 μmol h −1 and apparent quantum efficiency of 0.04% at 420 nm by using only 5 mg of photocatalysts. The higher photocatalytic activity could be ascribed to the appropriate amount of Pt ions doping and excellent electron-sink effect of Pt NPs co-catalysts. [ABSTRACT FROM AUTHOR]

Abstract: In this work, V-doped TiO2 nanofibers with different V contents have been fabricated by an electrospinning technique. The as-prepared nanofibers were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra, X-ray photoelectron spectroscopy (XPS), and UV–Vis diffuse reflectance (DR) spectroscopy. The results indicated that the V4+ or V5+ ions were successfully incorporated into the crystal lattice of anatase TiO2 nanofibers. Meanwhile, the V doping could extend the visible light absorption of TiO2 nanofibers. The photocatalytic experiments indicated that the obtained V-doped TiO2 nanofibers possessed high activity for the photodegradation of organic pollutant methylene blue (MB). Especially, the 1.0 and 5.0wt.% V-doped TiO2 nanofibers exhibited the best catalytic activity under visible and ultraviolet (UV) light irradiation, respectively. Also, these nanofibers could be easily recycled without a decrease of the photocatalytic activity. [Copyright &y& Elsevier]

Amine-functionalization of TiO2 nanoparticles, through a solvothermal approach, substantially increases the affinity of CO2 on TiO2 surfaces through chemisorption. This chemisorption allows for more effective activation of CO2 and charge transfer from excited TiO2, and significantly enhances the photocatalytic rate of CO2 reduction into methane and CO. [ABSTRACT FROM AUTHOR]

• The molecular-scale hetero-interface is achieved by assembling ultra-small HPW clusters onto g-C 3 N 4 nanosheets. • Abundant light-harvesting and catalytic sites expose on the HPW/g-C 3 N 4 hetero-interface. • The Z-scheme mechanism-enhanced photocatalytic solar-to-fuels conversion is demonstrated in the HPW/g-C 3 N 4 heterojunction. • The photocatalytic activity of HPW/g-C 3 N 4 heterojunction nanosheets is much higher than those of g-C 3 N 4 nanosheets. Rational assembly of small-sized photosensitizers onto 2D semiconductors can effectively promote the photocatalytic activity of the formed 2D heterojunction photocatalyst due to the hetero-interfacial charge-transfer process. However, the achievement of the 2D semiconductor-based heterojunction photocatalyst with the exposures of both abundant light-harvesting and catalytic sites at the hetero-interface region is still a huge challenge. Herein, we synthesized phosphotungstic acid/graphitic carbon nitride (HPW/g-C 3 N 4) heterojunction nanosheets (NSs) with the highly-dispersed distribution of ultra-small HPW clusters (1∼2 nm) by using a facile self-assembly method based on the static adsorption-deposition process. The formed molecular-scale hetero-interface between HPW clusters and g-C 3 N 4 NSs resulted in the exposure of abundant active-sites on the highly-dispersed HPW/g-C 3 N 4 hetero-interface. By combining the steady-state and transient photoluminescence spectra with the wavelength-controlled experiments, we demonstrated that the hetero-interfacial charge-transfer process occurring in the HPW/g-C 3 N 4 heterojunction NSs obeyed the Z-scheme mechanism rather than the common "type-II" heterojunction mechanism. In this way, the lifetimes of photoinduced electrons on the conduction band of g-C 3 N 4 could be prolonged for initiating the photocatalytic solar-to-fuels conversion. Upon interband excitations of both the two hetero-components in the HPW/g-C 3 N 4 heterojunction NSs, the photocatalytic activities of H 2 generation and CO 2 reduction could be enhanced by ∼2.2 and ∼6.7 times as compared to the pure g-C 3 N 4 NSs, even though the HPW component was photocatalytic-inert for either H 2 generation or CO 2 reduction upon UV–vis light irradiation. [ABSTRACT FROM AUTHOR]

In this work, the lacunary Keggin-type phosphotungstates of [PW9O34]9- (PW9) clusters were loaded onto the g-C3N4 nanosheets (NSs) to synthesize the phosphotungstate clusters-decorated 2D heterojunction photocatalysts by using the electrostatic-force driven self-assembly process. The surface charge polarity of g-C3N4 NSs was changed from a negative to a positive charge through the acidizing treatment. The positively-charged g-C3N4 NSs allowed the negatively-charged PW9 clusters to be adsorbed and deposited onto the g-C3N4 NSs, forming the PW9/g-C3N4 heterojunction NSs. The as-synthesized samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and UV-VIS absorption spectra, respectively. The photocatalytic activity tests indicated that, upon simulated sunlight irradiation, the photocatalytic H2-generation rate of PW9/g-C3N4 heterojunction NSs (~23.8 μmol h−1) was ~3.3 times higher than that of the pure g-C3N4 NSs (~7.3 μmol h−1). The enhanced photocatalytic activity of PW9 cluster-decorated g-C3N4 NSs could be attributed to the enhanced separation process of the photoinduced charge-carriers, due to the Z-scheme-mediate charge transfer behavior across their hetero-interface. [ABSTRACT FROM AUTHOR]

Macrostructural flexible photocatalysts have been proven to have desirable recyclable properties during the photocatalytic degradation of organic pollutants in water. However, the photocatalytic activities of these photocatalysts are often unsatisfactory due to the fast recombination of charge carriers and the limited surface active sites. Herein, we developed a novel flexible photocatalyst of AgBr/BiOBr/polyacrylonitrile (PAN) composite mats (CMs) through the controllable assembly of AgBr/BiOBr nano-heterostructures on electrospun polyacrylonitrile nanofibers (PAN NFs) via a three-step synthesis route. The component ratio of AgBr to BiOBr in the CMs could be easily adjusted by controlling the in situ ion exchange process. The charge–transfer process occurring at the interface of the AgBr/BiOBr nano-heterostructures strongly hindered the recombination of photoinduced electron–hole pairs, thereby effectively enhancing the photocatalytic activity of the AgBr/BiOBr/PAN CMs. Meanwhile, the unique hierarchical inorganic/organic heterostructure of the AgBr/BiOBr/PAN CMs not only led to good flexibility, but also provided an abundance of active sites for photocatalytic reactions. Upon visible-light irradiation, AgBr/BiOBr/PAN CMs with an optimal ratio of AgBr to BiOBr components exhibited both enhanced photocatalytic activity and excellent separability during the degradation of methyl orange in water compared to the BiOBr/PAN CMs. [ABSTRACT FROM AUTHOR]

The affinity of TiO2 nanoparticles for CO2 is greatly enhanced upon amine functionalization. In their Communication on page 10220 ff., C. Xue and co‐workers show that this enhanced chemisorption is coupled with a higher rate of photocatalytic reduction of CO2 into CH4 and CO. [ABSTRACT FROM AUTHOR]

With the rapid development of industry, organic pollutants and bacterial contamination in water resources are becoming increasingly severe. Photocatalysis is an effective approach to address this problem. ZnO, as a traditional n- type semiconductor photocatalyst, has a relatively wide bandgap, which results in a narrow range of light absorption and quick recombination of photogenerated charge carriers, thus limiting its development. In this work, we constructed p -type CuO/ n -type ZnO heterojunction nanofibers (HNFs) to extend the light harvesting range and improve the migration and separation of the photoinduced electrons and holes across the hetero-interface through. Afterwards, Ag nanoparticles were introduced into above HNF matrix to reinforce the photocatalytic activity. Results showed that, upon simulated sunlight irradiation, the Ag NPs-decorated p- type CuO/ n- type ZnO HNFs exhibited enhanced photocatalytic activities. After 20 min of simulated sunlight irradiation, approximately 98.5% of MB was degraded by 1.0 at% Ag NPs-decorated p- type CuO/ n- type ZnO HNFs. Additionally, after 10 min of irradiation, the disinfection efficiency of HNFs for Escherichia coli was > 99.99%. It is worth noting that this study has opened up a new pathway for the rational design of p-n junction photocatalysts with superior charge transfer properties, to achieve remarkable photocatalytic disinfection and degradation activities. [Display omitted] • A p -type CuO/ n -type ZnO photocatalyst was prepared, leading to the broadening of photoabsorption in the visible region. • The CuO/ZnO nanofibers possess excellent photocatalytic activity for the degradation of MB and disinfection of E. coli. • To further enhance the activity of binary photocatalysts, Ag nanoparticles were successfully modified on CuO/ZnO HNFs. • Ag nanoparticles-modified CuO/ZnO HNFs photocatalysts exhibit rapid dye degradation and bactericidal activity (<30 min). [ABSTRACT FROM AUTHOR]

In this letter, we developed a self-cleaning coating material through simply blending the TiO 2 porous microspheres (PMS) with the commercial cement. The TiO 2 PMS with the diameters around 500 nm were synthesized by an ultrasonic spray pyrolysis method. During the photocatalytic depollution tests, the as-prepared TiO 2 PMS/cement composite was processed into a hardened micro-film coated on the glass substrate via a doctor blade method. Upon UV–Vis light irradiation, the TiO 2 PMS/cement composite film exhibited the higher photocatalytic activity as compared to the conventional P25/cement composite film. This can be attributed to the fact that the unique micro-nano hierarchical porous structure of TiO 2 PMS not only boosts the light harvesting ability, but also provides more active sites for the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of 2D g-C 3 N 4 /SnS 2 /TiO 2 ternary photocatalyst was present. • g-C 3 N 4 /SnS 2 /TiO 2 showed broad photoresponsive range and promoted charge separation. • The continuous charge steps were fabricated at the hetero-interface of catalyst. • The photocatalytic disinfection activity of g-C 3 N 4 /SnS 2 /TiO 2 was highly enhanced. • Both O 2 - and h+ are responsible for photocatalytic process of g-C 3 N 4 /SnS 2 /TiO 2. The development of inexpensive and high-efficient semiconductor photocatalysts is of great significance for achieving the goal of environmental remediation. However, the fast recombination of the photoinduced charge-carriers in semiconductor photocatalysts still poses a huge obstacle. In this contribution, we pave "continuous charge steps" in multiple 2D-semiconductor hetero-interface through an orderly assembly of 2D semiconductors of g-C 3 N 4 , SnS 2 , and TiO 2 nanosheets (NSs) by using a facile ultrasonic dispersion and subsequent heat treatment. The matchable energy band structures between the above three 2D NSs allows their orderly composite (g-C 3 N 4 /SnS 2 /TiO 2 NSs) to possess two kinds of broad 2D hetero-interface configurations (g-C 3 N 4 /SnS 2 /TiO 2 and TiO 2 /g-C 3 N 4 /SnS 2) with the extended light-harvesting range. The time-resolved photoluminescence spectroscopy results prove that both of the above hetero-interface configurations could induce the formation of "continuous charge steps" to accelerate the interfacial electron transfer. Thus, upon UV–visible light irradiation, the as-synthesized g-C 3 N 4 /SnS 2 /TiO 2 NSs exhibited 4.2–7.5 fold enhancement for the photocatalytic degradation of Rhodamine B. Notably, the photocatalytic disinfection efficiency of the g-C 3 N 4 /SnS 2 /TiO 2 NSs for Escherichia coli could be over 99.99% after simulated sunlight irradiation for only 30 min. This study opens up a new path for sensible design of ternary heterostructure photocatalyst with continuous charge steps towards an extraordinary photocatalytic activity. [ABSTRACT FROM AUTHOR]

• TiO 2 /Cu 2 O/CuO CNFs is produced via a photoinduced phase-transition on the TiO 2 /CuO CNFs. • The TiO 2 /Cu 2 O/CuO CNFs exhibited the enhanced sensing property for glucose. • The sensitivity of TiO 2 /Cu 2 O/CuO CNFs depends on the TiO 2 content in the CNFs. • The sensing property of TiO 2 /Cu 2 O/CuO CNFs electrode is recoverable via the light irradiation. • The CNFs electrode possesses a good long-term stability, high anti-interference ability, and good reproducibility. The TiO 2 /Cu 2 O/CuO composite nanofibers (CNFs) were obtained via the photoinduced phase-transition process occurring in the electrospun TiO 2 /CuO CNFs. The TiO 2 /Cu 2 O/CuO CNFs electrode showed the higher sensitivity (2074.7 µA·mM−1·cm−2; 0–2 mM) than the pure CuO NFs, TiO 2 NFs, and TiO 2 / CuO CNFs electrodes, respectively. The enhanced glucose sensing performance is attributed to the existence of multiple valence-states and redox-couples in TiO 2 /Cu 2 O/CuO CNFs to promote the redox reaction. [Display omitted] Constructing metal-oxide-based composites with the multiple valence-states and redox-couples has been proved as an effective strategy to enhance the performance of non-enzymatic glucose sensing. Herein, we report a mild and efficient method to prepare multiple-valent copper-based oxide composite nanofibers (Cu x O CNFs) through introducing the TiO 2 photosensitizer into the CuO NFs for actuating the localized phase transition from tenorite CuO (Cu2+) to cuprite Cu 2 O (Cu+) upon UV–visible light irradiation. The sensitivity of the obtained TiO 2 /Cu 2 O/CuO CNFs for glucose sensing (0–2 mM) could be enhanced by 1.12–1.31 times as compared to that of the TiO 2 /CuO CNFs. The enhanced sensitivity is dependent on the TiO 2 -content in the primal TiO 2 /CuO CNFs. When introducing 5.0 at.% of TiO 2 into the CuO nanofibers, the photoinduced phase-transition process could result in the formation of optimal TiO 2 /Cu 2 O/CuO CNFs with the component ratio of Cu 2 O to CuO at 0.46:1. This TiO 2 /Cu 2 O/CuO CNFs (2074.7 µA·mM−1·cm−2; 0.25 µM) exhibited nearly 1.32-fold improvement on the sensitivity and 3.0-fold enhancement on the detection limit as compared to the corresponding values of the pure CuO electrospun nanofibers (1581 µA·mM−1·cm−2; 0.75 µM). After the continuous measurements for 14 days, the sensitivity of the optimal sample could maintain 89.4% of its initial value. Notably, its sensitivity could be further recovered to 97.4% of the initial value after UV–visible light irradiation for 1 h. [ABSTRACT FROM AUTHOR]

The long-range transfer of photoinduced charge-carriers was realized in the well-designed all 2D-layered heterojunction photocatalyst, which led to remarkable enhancements of both photocatalytic oxidation and reduction activities. [Display omitted] • A photo-assisted self-assembly strategy for making 2D heterojunction photocatalysts. • The novel 2D heterojunction photocatalyst is made of 2D-layered SnS 2 , RGO, and g-C 3 N 4. • An interesting long-range spatial separation of charge-carriers is realized. • The 2D heterojunction photocatalyst exhibits the enhanced photocatalytic redox ability. Constructing heterojunction photocatalysts has been proven as an ingenious tactic to adjust the lifetimes of the higher redox-active charge-carriers toward highly-efficient photocatalytic applications. Numerous recent efforts focused on the short-range spatial separation of charge-carriers in the heterojunction photocatalysts. However, engineering a long-range transfer channel in the well-designed heterojunction photocatalyst to further spatially separate the charge-carriers is still a huge challenge. In this contribution, we developed a facile photo-assisted self-assembly strategy to synthesize the all 2D-layered heterojunction photocatalysts of SnS 2 /RGO/g-C 3 N 4 nanosheets (NSs). During the synthesis process, the precursor of 2D graphene-oxide (GO) NSs was converted into the reduced GO (RGO) NSs by the photoactive semiconductors of 2D SnS 2 and g-C 3 N 4 NSs. Meanwhile, the above two 2D semiconductors were simultaneously anchored onto the surface of the RGO NSs. Upon visible-light irradiation of the synthesized SnS 2 /RGO/g-C 3 N 4 NSs, the 2D RGO component could provide a broad electron-transfer surface for the long-range spatial-separation of charge-carriers in the semiconductor components of the NSs. Thus, this all 2D-layered heterojunction photocatalyst exhibited ∼ 9.2 and ∼ 4.6-fold enhancement on the photocatalytic oxidation degradation of the organic dye, and ∼ 68 and ∼ 3.4-fold enhancement on photocatalytic protons reduction as compared to the pure SnS 2 and g-C 3 N 4 NSs, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Zn2TiO4@carbon core/shell nanofibers (Zn2TiO4@C NFs) with different thickness of carbon layers (from 2 to 8nm) were fabricated by combining the electrospinning technique and hydrothermal method. The results showed that a uniform carbon layer was formed around the electrospun Zn2TiO4 nanofiber (Zn2TiO4 NFs). By adjusting the hydrothermal fabrication parameters, the thickness of carbon layer varied linearly with the concentration of glucose. Furthermore, the core/shell structure formed between Zn2TiO4 and carbon enhanced the charge separation of pure Zn2TiO4 under ultraviolet excitation, as evidenced by photoluminescence spectra. The photocatalytic studies revealed that the Zn2TiO4@C NFs exhibited enhanced photocatalytic efficiency of photodegradation of Rhodamine B (RB) compared with the pure Zn2TiO4 NFs under ultraviolet excitation, which might be attributed to the high separation efficiency of photogenerated electrons and holes based on the synergistic effect between carbon and Zn2TiO4. Notably, the Zn2TiO4@C NFs could be recycled easily by sedimentation without a decrease of the photocatalytic activity. [Copyright &y& Elsevier]

Abstract: One-dimensional 2,9,16,23-tetra-nitrophthalocyanine iron(II) (TNFePc)/TiO2 nanofiber heterostructures have been successfully obtained by a simple combination of electrospinning technique and solvothermal process. The as-obtained products were characterized by field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDX) spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and IR spectrum. The results revealed that the TNFePc nanosheets were successfully grown on the primary TiO2 nanofibers. And, the coverage density of the secondary TNFePc nanostructures could be controlled by adjusting the experimental parameters. Photocatalytic tests displayed that the H2O2 assisted TNFePc/TiO2 nanofiber heterostructures (TNFePc/TiO2–H2O2) possessed a much higher degradation rate of methyl orange than the pure TiO2 and TNFePc/TiO2 nanofiber without H2O2 under visible light. Moreover, the TNFePc/TiO2 nanofiber heterostructures could be easily recycled without the decrease of the photocatalytic activity due to their one-dimensional nanostructural property of TiO2 nanofibers. [Copyright &y& Elsevier]

Abstract: A novel photocatalyst of nanostructured cadmium phthalocyanine (CdPc) immobilized on the surface of polyacrylonitrile (PAN) nanofibers had been successfully fabricated by a simple combination of electrospinning technique and the solvent-thermal process. FE-SEM micrographs indicated that the nanostructured CdPc uniformly immobilized on the surface of PAN nanofibers without agglomeration. And the obtained CdPc/PAN composite nanofibers exhibited high visible light photocatalytic activity for the degradation of rhodamine B. Moreover, this photocatalyst could be easily separated for reuse due to the one-dimensional nanostructural property of the CdPc/PAN composite nanofibers. [Copyright &y& Elsevier]

• TiO 2 was synthesized by a solvothermal method and treated with N-plasma at atmospheric pressure. • Ti3+ ions of N-TiO 2 form the Ti3+ self-doped system, which causing the light absorption range enhanced. • The catalytic H 2 evolution of N-TiO 2 is 14.85 times higher than that of the pristine TiO 2 NFs. [Display omitted] The N-TiO 2 was prepared by N-plasma treatment at room temperature and ambient, which caused the results of higher generation of oxygen vacancy. The reaction also resulted in reducing more Ti3+, and forming the Ti3+ self-doped system, changing the electronic structure of Ti3+, enhancing its light absorption range, and then enhancing its photocatalytic activity. The photocatalytic activity was ~14.85 times higher than that of the pristine TiO 2. An enhancement of the photocatalytic activity of Titanium dioxide nanosheets (TiO 2 NFs) by N 2 plasma (N-plasma) treatment has been suggested. TiO 2 NFs was synthesized by a solvothermal method and treated with N-plasma at atmospheric pressure. Then the as-prepared TiO 2 and N-plasma treated TiO 2 (N-TiO 2) NFs photocatalyst were extensively characterized. Interestingly, more oxygen vacancy and Ti3+ ions were found in the N-TiO 2 NFs. Meanwhile, Ti3+ ions form the Ti3+ self-doped system, which causing the light absorption range enhanced. The catalytic H 2 evolution of N-TiO 2 NFs at a rate of 8.1 mmol g−1 h−1, which is 14.85 times higher than that of the pristine TiO 2 NFs. These results might suggest new views for the photoactivity of TiO 2 NFs and provide a kind of feasibility for other metal oxides in the photocatalytic field. [ABSTRACT FROM AUTHOR]

Amine-functionalization of TiO2 nanoparticles, through a solvothermal approach, substantially increases the affinity of CO2 on TiO2 surfaces through chemisorption. This chemisorption allows for more effective activation of CO2 and charge transfer from excited TiO2, and significantly enhances the photocatalytic rate of CO2 reduction into methane and CO. [ABSTRACT FROM AUTHOR]

A flexible schottky-junction nanofiber membrane (NFM) consisted of rutile TiO 2 nanoparticles-decorated electrospun carbon NFs is fabricated to proactively capture and simultaneously in-situ convert the PM pollution. The filtration efficiency of this NFM for the ultrafine PM 0.3 reaches 92.98 %. More interestingly, some of the carbonaceous PM on the NFM can be converted into the fuels of such CO and CH 4 through a multi-step photoreaction. • A new idea is proposed to proactively capture and in-situ convert PM pollutions. • Flexible membranes of TiO 2 /carbon schottky-junction is new valid PM-filters. • Multilevel polarization fields in the membrane can enhance PM-capture abilities. • Some captured PM can be converted into CO and CH 4 via in-situ photoreactions. Atmospheric Particulate matter (PM) with small sizes has caused a serious air-pollution problem calling for high-performance PM-capture materials and promising remediation strategies. In this contribution, we propose a new idea to proactively capture PM and simultaneously in-situ convert the captured PM pollution over the flexible schottky-junctions nanofiber membrane (NFM) consisting of rutile TiO 2 nanoparticles (NPs)-decorated electrospun carbon NFs. We also demonstrate that both the interfacial electron-transfer process at the TiO 2 /carbon schottky-junctions and the photo-excitation process at the surface of TiO 2 NPs can induce polarization fields in the TiO 2 /carbon NFM due to the difference of the space-charge distribution. These multilevel polarization fields can drive the long-range electrostatic force to enhance the proactive PM-capture ability of the NFM. As such, the TiO 2 /carbon NFM exhibited a satisfactory quality factor (0.11 Pa−1) for balancing the PM 2.5 -filtration efficiency (99.92 %) and the pressure drop (only 63 Pa). More importantly, upon UV–vis-light irradiation, 92.98 % of the ultrafine PM 0.3 was removed over this TiO 2 /carbon NFM. Furthermore, the as-captured PM on the NFM could be photocatalytically decomposed by the photoactive-component of TiO 2 NPs, during which some of the carbonaceous PM was converted into the fuels of such CO and CH 4 through a multi-step photoreaction. [ABSTRACT FROM AUTHOR]