Exploring the Effects of the Photochromic Response and Crystallization on the Local Structure of Noncrystalline Niobium Oxide

Niobium oxide (Nb2O5) is a versatile semiconductor material with photochromic properties. This study investigates the local structure of noncrystalline, short-range-ordered niobium oxide synthesized via a sol-gel method. X-ray atomic pair distribution function analysis unravels the structural arrangements within the noncrystalline materials at a local scale. In the following, in situ scattering and diffraction experiments elucidate the heat-induced structure transformation of the amorphous material into crystalline TT-Nb2O5 at 550 °C. In addition, the effect of photocatalytic conditions on the structure of the material was investigated by exposing the short-range-ordered and crystalline materials to ultraviolet light, resulting in a reversible color change from white to dark brown or blue. This photochromic response is due to the reversible elongation of the nearest Nb-O neighbors, as shown by local structure analysis based on in situ PDF analyses. Optical band gap calculations based on the ultraviolet-visible spectra collected for both the short-range-ordered and crystalline materials show that the band gap values reduced for the darkened materials return to their initial state after bleaching. Furthermore, electron energy loss spectroscopy reveals the reduction of Nb5+ to Nb4+ centers as a persistent effect. The study establishes a correlation between the band gap and the structure of niobium oxide, providing insights into the structure-performance relation at the atomic level.

Photomodulated cryogenic temperature sensing through a photochromic reaction in Na0.5Bi2.5Ta2O9: Er/Yb multicolour upconversion

Optical temperature sensing of the non-thermally coupled energy levels (N-TCLs) based on fluorescence intensity ratio (FIR) technologies has excellent temperature sensitivity and signal recognition properties. In this study, a novel strategy is established to enhance the low-temperature sensing properties by controlling photochromic reaction process in Na_0.5Bi_2.5Ta₂O₉: Er/Yb samples. The maximum relative sensitivity reaches up to 5.99% K^-1 at cryogenic temperature of 153 K. After irradiation with commercial laser of 405 nm for 30 s, the relative sensitivity is increased to 6.81% K^-1. The improvement is verified to originate from the coupling of optical thermometric and photochromic behaviour at the elevated temperatures. The strategy may open up a new avenue to improve the thermometric sensitivity in photo-stimuli response photochromic materials.

Enhanced Acidic Water Oxidation by Dynamic Migration of Oxygen Species at the Ir/Nb2 O5-x Catalyst/Support Interfaces

Catalyst/support interaction plays a vital role in catalysis towards acidic oxygen evolution (OER), and the performance reinforcement is currently interpreted by either strain or electron donation effect. We herein report that these views are insufficient, where the dynamic evolution of the interface under potential bias must be considered. Taking Nb₂ O_5-x supported iridium (Ir/Nb₂ O_5-x ) as a model catalyst, we uncovered the dynamic migration of oxygen species between IrO_x and Nb₂ O_5-x during OER. Direct spectroscopic evidence combined with theoretical computation suggests these migrations not only regulate the in situ Ir structure towards boosted activity, but also suppress its over-oxidation via spontaneously delivering excessive oxygen from IrO_x to Nb₂ O_5-x . The optimized Ir/Nb₂ O_5-x thus demonstrated exceptional performance in scalable water electrolyzers, i.e., only need 1.839 V to attain 3 A cm^-2 (surpassing the DOE 2025 target), and no activity decay during a 2000 h test at 2 A cm^-2 .

Giant tunability of upconversion photoluminescence in Er3+-doped (K, Na)NbO3 single crystals

Perovskite oxides with luminescent ions hold great promise in optoelectronic devices because of their outstanding thermal stabilities and electro-optic performance. As one typical perovskite upconversion (UC) host material, lead-free potassium sodium niobate ((K, Na)NbO3/(KxNa1-x)NbO3 or KNN) has attracted much attention in recent years. In the present work, a novel routine was developed to tune the upconversion photoluminescence (UC PL) performance by controlling the oxygen vacancy concentration in the KNN matrix, based on the 0.1% Er3+-doped KNN (Er-KNN) single crystals grown for the first time. UC PL properties, conductivity and defect chemistry of the single crystals were systematically investigated. The UC PL intensity of the as-grown Er-KNN material could be enhanced by 20 times after oxygen atmosphere annealing at 800 °C and fully quenched after vacuum annealing. What's more, by annealing under an oxygen atmosphere and vacuum, the conductivity of the Er-KNN sample was successfully tuned for more than 8 orders of magnitude. The super-wide range tunability of UC PL performance and conductivity could be explained by oxygen vacancies which gave rise to Nb5+-Nb4+ valence alternation. Because of the modulated photoluminescence properties and conductivity, our grown Er-KNN single crystals have great potential for use in multifunctional devices.

A Facile One-Pot Synthesis of Biomimetic Photocatalyst Zn(II)-Porphyrin-Sensitized 3D TiO2 Hollow Nanoboxes and Synergistically Enhanced Visible-Light Degradation

A serials of biomimetic photocatalyst zinc(II) meso-tetra(4-carboxyphenyl)porphyrinato (ZnTCP)-sensitized 3D hierarchical TiO2 hollow nanoboxes (TiO2-HNBs) assembled by six ordered nanosheets with dominant {001} facets exposure (ZnTCP@TiO2-HNBs) have been successfully synthesized by a facile one-pot solvothermal method via a topological transformation process with TiOF2 as template. Infrared spectra (IR), UV-vis spectroscopy, and X-ray photoelectron spectroscopy (XPS) confirmed that ZnTCP played a decisive role in constructing 3D hollow nanoboxes through the formation of ester bond combined to TiO2-HNBs, which also provided a transferring photo excited electrons bridge to sensitize TiO2-HNBs for enhancing visible-light response. Due to the superior sensitization and biomimetic activity of ZnTCP, the photodegradation rate of rhodamine B (RhB) of as-prepared ZnTCP@TiO2-HNBs with ZnTCP/TiOF2 mass ratio of 2% (T-2p) improves 3.6 times compared to that of TiO2-HNBs with a degradation yield of 99% for 2 h under simulated sunlight irradiation (> 420 nm). The enhanced photodegradation ability was attributed to synergistic visible photocatalytic mechanism of biomimetic catalyst, which can not only produce hydroxyl radical (•OH) and superoxide radical (•O2-) coming from the excitation process of ZnTCP sensitized TiO2-HNBs, but also generate singlet oxygen (1O2) that was only provided by biomimetic enzyme porphyrins. Furthermore, the photocatalyst showed good recycling stability and dispersibility after five rounds, ascribed to ZnTCP strong chemical bonding to the support TiO2-HNBs. By means of electrochemical cyclic voltammetry analysis, the effect of central zinc ions and parent porphyrin rings on the redox property of biomimetic catalyst was studied.

Gold nanoparticle-functionalized niobium oxide perovskites as photocatalysts for visible light-induced aromatic alcohol oxidations

Spherical gold nanoparticles have been supported onto the surface of potassium niobium oxide perovskites, an underdeveloped class of semiconductor in photocatalytic organic transformations. The nanoparticle dopants of 9.5 nm in diameter and surface plasmon absorption at 530 nm are examined as possible visible light induced catalysts using alcohol photooxidation as the probe reaction. The nanomaterial-induced photooxidation of a series of aromatic alcohols is examined, in the absence of solvent, as a function of base, H2O2, and catalyst concentrations, as well as using multiple visible light sources. This experimental methodology affords extremely selective photooxidation to the carbonyl products (>99%) in as little as 2 h. Using the results obtained from the substitution of the aromatic alcohol, the proposed photocatalytic mechanism is suggested to rely heavily on plasmon-initiated electron transfer from the gold nanoparticle surface to the potassium niobium oxide perovskite and subsequent reductive decomposition of H2O2. This photodegradation step is proposed to favor the formation of ketyl radical species, a key intermediate in the visible light induced mechanism that undergoes both an electron and proton transfer to facilitate formation of the final, carbonyl products. Furthermore, the gold nanoparticle – potassium niobium oxide catalyst exhibits moderate reusability, highly desired in the realm of heterogeneous catalysis.

In situ formation of NbOx@NbN microcomposites: seeking potential in photocatalytic and Li-ion battery applications

A NbO_x@NbN microcomposite formed by in situ partial thermal oxidation is revealed to be potentially advantageous in photocatalytic hydrogen production and lithium-ion storage.

Light-activated Ullmann homocoupling of aryl halides catalyzed using gold nanoparticle-functionalized potassium niobium oxides

Lamellar, or layered, potassium niobium oxide perovskites are a class of underdeveloped semiconductors in organic photocatalysis that offer the inherent advantages of larger particle size and ease of recoverability as compared to traditional semiconductor materials.

Enhanced photocatalytic performance and stability of visible-light-driven Z-scheme CdS/Ag/g-C3N4 nanosheets photocatalyst

A novel Z-scheme CdS/Ag/g-C₃N₄ nanosheets photocatalyst was synthesized by combining the hydrothermal and photo-deposition techniques, where Ag nanoparticles as carrier transport channels significantly improve the separation efficiency of electron–hole pairs.

An unsaturated metal site-promoted approach to construct strongly coupled noble metal/HNb3O8 nanosheets for efficient thermo/photo-catalytic reduction

Creating two-dimensional (2D) crystal-metal heterostructures with an ultrathin thickness has spurred increasing research endeavors in catalysis because of its fascinating opportunities in tuning the electronic state at the surface and enhancing the chemical reactivity. Here we report a novel and facile Nb⁴⁺-assisted strategy for the in situ growth of highly dispersed Pd nanoparticles (NPs) on monolayer HNb₃O₈ nanosheets (HNb₃O₈ NS) constituting a 2D Pd/HNb₃O₈ NS heterostructure composite without using extra reducing agents and stabilizing agents. The Pd NP formation is directed via a redox reaction between an oxidative Pd salt precursor (H₂PdCl₄) and reductive unsaturated surface metal (Nb⁴⁺) sites induced by light irradiation on monolayer HNb₃O₈ NS. The periodic arrangement of metal Nb nodes on HNb₃O₈ NS leads to a homogeneous distribution of Pd NPs. Density functional theory (DFT) calculations reveal that the direct redox reaction between the Nb⁴⁺ and Pd²⁺ ions leads to a strong chemical interaction between the formed Pd metal NPs and the monolayer HNb₃O₈ support. Consequently, the as-obtained Pd/HNb₃O₈ composite serves as a highly efficient bifunctional catalyst in both heterogeneous thermocatalytic and photocatalytic selective reduction of aromatic nitro compounds in water under ambient conditions. The achieved high activity originates from the unique 2D nanosheet configuration and in situ Pd incorporation, which leads to a large active surface area, strong metal-support interaction and enhanced charge transport capability. Moreover, this facile Nb⁴⁺-assisted synthetic route has demonstrated to be general, which can be applied to load other metals such as Au and Pt on monolayer HNb₃O₈ NS. It is anticipated that this work can extend the facile preparation of noble metal/nanosheet 2D heterostructures, as well as promote the simultaneous capture of duple renewable thermal and photon energy sources to drive an energy efficient catalytic process.

Oxygen-Induced Bi5+-Self-Doped Bi4V2O11 with a p-n Homojunction Toward Promoting the Photocatalytic Performance

Bi⁵⁺-self-doped Bi₄V₂O₁₁ (Bi⁵⁺-BVO) nanotubes with p-n homojunctions are fabricated via an oxygen-induced strategy. Calcinating the as-spun fibers with abundant oxygen plays a pivotal role in achieving Bi⁵⁺ self-doping. Density functional theory calculations and experimental results indicate that Bi⁵⁺ self-doping can narrow the band gap of Bi₄V₂O₁₁, which contributes to enhancing light harvesting. Moreover, Bi⁵⁺ self-doping endows Bi₄V₂O₁₁ with n- and p-type semiconductor characteristics simultaneously, resulting in the construction of p-n homojunctions for retarding rapid electron-hole recombination. Benefiting from these favorable properties, Bi⁵⁺-BVO exhibits a superior photocatalytic performance in contrast to that of pristine Bi₄V₂O₁₁. Furthermore, this is the first report describing the achievement of p-n homojunctions through self-doping, which gives full play to the advantages of self-doping.

Facile preparation of protonated hexaniobate nanosheets and its enhanced photocatalytic activity

Exfoliated hexaniobate nanosheets E-H₂K₂Nb₆O_17-x (E-HKNO) with broad light absorption (up to 850 nm) and high adsorption properties were prepared via ion exchange and transient annealing processes with micron-size K₄Nb₆O₁₇ powders as the precursor. The as-prepared E-HKNO nanosheets show excellent visible light photodegradation performances when compared to degussa P25, which was evaluated in terms of degradation of Rhodamine B (Rh B). High adsorption and broad light absorption characteristics could be attributed to the exfoliation behavior and the reduction of surface Nb⁵⁺ to Nb⁴⁺, which was confirmed by x-ray photoelectron spectroscopy (XPS) and Raman spectra. From the Mott-Schottky analysis, the E-HKNO is an n-type semiconductor and has a higher flat band voltage (-0.46 V versus RHE at pH = 7), compared with K₄Nb₆O₁₇. In addition, the electrochemical impedance spectroscopy (EIS) indicates that the E-HKNO nanosheets have an increased semiconductor-electrolyte charge transfer resistance, which is not conducive to the separation of photogenerated carriers (e^--h⁺). Accordingly, a small amount of holes scavenger (EDTA) was added to improve the photodegradation performance of the E-HKNO, since the holes scavenger can inhibit the recombination of the photogenerated carriers. This work provides not only a facile method for the preparation of an efficient E-HKNO nanosheets photocatalyst, but also new insights for further enhancing the photodegradation performance by adding trace scavenger.

Exploring optoelectronic properties and mechanisms of layered ferroelectric K4Nb6O17 nanocrystalline films and nanolaminas

Two-dimensional layered K₄Nb₆O₁₇ (KN) was easily formed as a secondary phase caused by the volatilization of alkali metal ions, when preparing ferroelectric K_xNa_1−xNbO₃ based ceramics and films. In this work, it was believed that KN film is with weak ferroelectricity and has a little effect on the ferroelectric properties of K_xNa_1−xNbO₃ based films. Moreover, temperature dependent (77–500 K) dielectric functions of KN film have been firstly extracted by fitting ellipsometric spectra with the Adachi dielectric function model and a four-phase layered model. The high-frequency dielectric constant linearly increases and optical band gap slightly decreases with increasing the temperature. We also research its photoelectrochemical properties and its application in high-efficient light-induced H₂ evolution. In addition, X-ray photoelectron spectroscopy, Raman scattering, temperature dependent transmittance and infrared reflectance spectra, and first-principles calculation were conjointly performed to further reveal the intrinsic optoelectronic features and relevant mechanisms of KN.

Exploiting the photocatalytic activity of gold nanoparticle-functionalized niobium oxide perovskites in nitroarene reductions

Novel gold nanoparticle@niobium oxide perovskite composites promote the photoreduction of para-substituted nitroarenes, where electron-withdrawing groups accelerate the photocatalytic reaction.

The impact of nitrogen doping and reduced-niobium self-doping on the photocatalytic activity of ultra-thin Nb3O8− nanosheets

Ultra-thin [Nb₃O₈]⁻ nanosheets with N doping, reduced-Nb doping and N/reduced-Nb codoping were fabricated by combining chemically controlled syntheses and liquid exfoliation, which enable comparative studies on the doping effect for photocatalytic H₂ evolution.

Boosted adsorption–photocatalytic activities and potential lithium intercalation applications of layered potassium hexaniobate nano-family

We demonstrated that the KN nano-family (including KN nanolaminas and nano hollow spheres) can be derived from the same Nb₂O₅-based hydrothermal reaction.

Smart Utilization of Carbon Dots in Semiconductor Photocatalysis

Efficient capture of solar energy will be critical to meeting the energy needs of the future. Semiconductor photocatalysis is expected to make an important contribution in this regard, delivering both energy carriers (especially H₂ ) and valuable chemical feedstocks under direct sunlight. Over the past few years, carbon dots (CDs) have emerged as a promising new class of metal-free photocatalyst, displaying semiconductor-like photoelectric properties and showing excellent performance in a wide variety of photoelectrochemical and photocatalytic applications owing to their ease of synthesis, unique structure, adjustable composition, ease of surface functionalization, outstanding electron-transfer efficiency and tunable light-harvesting range (from deep UV to the near-infrared). Here, recent advances in the rational design of CDs-based photocatalysts are highlighted and their applications in photocatalytic environmental remediation, water splitting into hydrogen, CO₂ reduction, and organic synthesis are discussed.

Visible and Near-Infrared Photothermal Catalyzed Hydrogenation of Gaseous CO2 over Nanostructured Pd@Nb2O5

The reverse water gas shift (RWGS) reaction driven by Nb2O5 nanorod-supported Pd nanocrystals without external heating using visible and near infrared (NIR) light is demonstrated. By measuring the dependence of the RWGS reaction rates on the intensity and spectral power distribution of filtered light incident onto the nanostructured Pd@Nb2O5 catalyst, it is determined that the RWGS reaction is activated photothermally. That is the RWGS reaction is initiated by heat generated from thermalization of charge carriers in the Pd nanocrystals that are excited by interband and intraband absorption of visible and NIR light. Taking advantage of this photothermal effect, a visible and NIR responsive Pd@Nb2O5 hybrid catalyst that efficiently hydrogenates CO2 to CO at an impressive rate as high as 1.8 mmol gcat-1 h-1 is developed. The mechanism of this photothermal reaction involves H2 dissociation on Pd nanocrystals and subsequent spillover of H to the Nb2O5 nanorods whereupon adsorbed CO2 is hydrogenated to CO. This work represents a significant enhancement in our understanding of the underlying mechanism of photothermally driven CO2 reduction and will help guide the way toward the development of highly efficient catalysts that exploit the full solar spectrum to convert gas-phase CO2 to valuable chemicals and fuels.

Constructing bulk defective perovskite SrTiO3 nanocubes for high performance photocatalysts

Defects (Ti³⁺ or oxygen vacancies) have been demonstrated to promote the charge separation process in TiO₂ based photocatalysts. Particularly, the bulk defects within a certain concentration can give a great enhancement for both light absorption and charge separation efficiency. In this report, we explored a one-step molten salts route to synthesize SrTiO₃ nanocubes with bulk defects (Ti³⁺ doped) by using SrCO₃ as a Sr source, and TiO₂ and Ti powder as Ti sources. The amount of defects can be tuned by changing the molar ratio of Ti/TiO₂. The corresponding bandgap of SrTiO₃ can be changed from 3.29 to 2.73 eV with the increase of defects. X-ray diffraction and electron microscopy disclose that SrTiO₃ is highly crystalline and has a cubic morphology. X-ray photoelectron spectroscopy and electron paramagnetic resonance indicate that the as-prepared SrTiO₃ is close to the Ti³⁺ doped SrTiO₃. Surface photovoltage spectroscopy (SPS) and field-induced SPS confirm that Ti³⁺ doping in the SrTiO₃ turns it from an n-type semiconductor to p-type. The SrTiO₃ with an optimal amount of defects exhibits highly enhanced photocatalytic performance. An excess amount of defects results in a weak SPS response and photocatalytic performance.

Multicolour photochromism of colloidal solutions of niobate nanosheets intercalated with several kinds of metal ions

Colourless and transparent colloidal solutions of niobate nanosheets intercalated with some kinds of metal ions (M-NNS, M: metal) showed quasi-reversible photochromism. Ultraviolet light irradiation of the solutions induced a change in color while maintaining the transparency, and the color change was dependent on the metal ions. The coloured solutions were bleached by exposure to an oxidizing atmosphere. This cycle could be repeated several times.

Surface Defects Enhanced Visible Light Photocatalytic H2 Production for Zn-Cd-S Solid Solution

In order to investigate the defect effect on photocatalytic performance of the visible light photocatalyst, Zn-Cd-S solid solution with surface defects is prepared in the hydrazine hydrate. X-ray photoelectron spectra and photoluminescence results confirm the existence of defects, such as sulfur vacancies, interstitial metal, and Zn and Cd in the low valence state on the top surface of solid solutions. The surface defects can be effectively removed by treating with sulfur vapor. The solid solution with surface defect exhibits a narrower band gap, wider light absorption range, and better photocatalytic perfomance. The optimized solid solution with defects exhibits 571 μmol h(-1) for 50 mg photocatalyst without loading Pt as cocatalyst under visible light irradiation, which is fourfold better than that of sulfur vapor treated samples. The wavelength dependence of photocatalytic activity discloses that the enhancement happens at each wavelength within the whole absorption range. The theoretical calculation shows that the surface defects induce the conduction band minimum and valence band maximum shift downward and upward, respectively. This constructs a type I junction between bulk and surface of solid solution, which promotes the migration of photogenerated charges toward the surface of nanostructure and leads to enhanced photocatalytic activity. Thus a new method to construct highly efficient visible light photocatalysts is opened.

Niobate nanoscroll composite with Fe2O3 particles under moderate conditions: assembly and application research

Fe₂O₃ nanoparticles are crosslinked to the niobate nanoscroll surface by association with terminal Nb–OH groups.

A metastable cubic phase of sodium niobate nanoparticles stabilized by chemically bonded solvent molecules

A facile and green alternative was provided to prepare a metastable phase of cubic NaNbO₃ nanoparticles. A new insight into the stabilization of cubic NaNbO₃ nanoparticles by chemically bonded organic molecules was proposed on the basis of systematic structural and surface analyses.

Controllable doping of nitrogen and tetravalent niobium affords yellow and black calcium niobate nanosheets for enhanced photocatalytic hydrogen evolution

Yellow (N-doped) and black (N-/Nb⁴⁺-codoped) [Ca₂Nb₃O₁₀]⁻ nanosheets with molecular thickness were fabricated by liquid exfoliation of selectively doped KCa₂Nb₃O₁₀ perovskite.

Facile synthesis of ultrathin SnNb2O6 nanosheets towards improved visible-light photocatalytic H2-production activity

Ultrathin SnNb₂O₆ nanosheets with enhanced visible-light photocatalytic H₂-production activity were prepared for the first time via a facile hydrothermal route using ultrathin K₄Nb₆O₁₇ nanosheets as the precursor.

Synchronously Achieving Plasmonic Bi Metal Deposition and I(-) Doping by Utilizing BiOIO3 as the Self-Sacrificing Template for High-Performance Multifunctional Applications

Herein, we uncover simultaneously achieving plasmonic Bi metal deposition and I(-) doping by employing wide-band-gap BiOIO3 as the self-sacrificing template. It was synthesized via a facile NaBH4-assisted in situ reduction route under ambient conditions. The reducing extent as well as photocatalytic levels can be easily modulated by controlling the concentration of NaBH4 solution. It is interesting that the band gap of BiOIO3 can be continuously narrowed by the modification, and the photoresponse range is drastically extended to cover the whole visible region. Bi/I(-) codecorated BiOIO3 not only exhibits profoundly upgraded photoreactivity in comparison with pristine BiOIO3 but also shows universally strong photooxidation properties toward decomposition of multiple industrial contaminants and pharmaceutical, including phenol, 2,4-Dichlorophenol (2,4-DCP), bisphenol A (BPA), dye model Rhodamine (RhB), tetracycline hydrochloride, and gaseous NO under visible light (λ ≥ 420 nm) or simulated solar light irradiation. It also outperforms the well-known and important photocatalysts C3N4, BiOBr, and Bi2WO6 for NO removal. The cooperative effects from Bi SPR and I(-) doping endow BiOIO3 with a narrowed band gap and highly boosted separation of charge carriers, thus responsible for the outstanding catalytic activity. The present study provides an absorbing candidate for practical environmental applications and also furthers our understanding of developing high-performance photocatalysts by manipulating manifold strategies in a facile way.

Yolk@Shell Nanoarchitecture of Au@r-GO/TiO₂ Hybrids as Powerful Visible Light Photocatalysts

Yolk@shell nanostructures of Au@r-GO/TiO2 with mesoporous shells were prepared by a sol-gel coating process sequentially with GO and TiO2 on Au/SiO2 core/shell spheres, followed by calcination and template removal, where the silica interlayer acts as a template not only to produce the void space but also to promote the coating of the r-GO and TiO2 layer. The evaluation of visible light photocatalytic activities in dye decomposition and water-splitting H2 production demonstrated their superior photocatalytic performance, which indicates their potential as powerful photocatalysts.

Colloidal Synthesis of Quaternary Wurtzite Cu3 AlSnS5 Nanocrystals and Their Photoresponsive Properties

Novel wurtzite Cu₃ AlSnS₅ nanocrystals with uniform size and shape are synthesized for the first time using a facile colloidal synthetic approach. The nanocrystals are characterized in detail and have a band gap of 1.35 eV. The photoresponsive behavior indicates their potential application in solar energy conversion devices.

Bilayer TiO2photoanode consisting of a nanowire–nanoparticle bottom layer and a spherical voids scattering layer for dye-sensitized solar cells

A bilayer TiO₂photoanode prepared by a one-time spray technique on a TiO₂NW array shows significantly enhanced photovoltaic performance in DSSCs.

Steering charge kinetics in photocatalysis: intersection of materials syntheses, characterization techniques and theoretical simulations

This review outlines the recent progress on probing and steering charge kinetics toward designing highly efficient photocatalysts.

Controlling interfacial contact and exposed facets for enhancing photocatalysis via 2D–2D heterostructures

The BiOIO₃/BiOI 2D–2D layered heterostructures with intimate contact and exposed reactive facets endowed the heterostructures with highly enhanced visible photocatalysis.

Diethylenetriamine-assisted hydrothermal synthesis of dodecahedral α-Fe2O3 nanocrystals with enhanced and stable photoelectrochemical activity

A facile diethylenetriamine-assisted protocol is developed to prepare dodecahedral α-Fe₂O₃ nanocrystals, which exhibit efficient photoelectrocatalytic water splitting activity.

A novel heterogeneous hybrid by incorporation of Nb2O5 microspheres and reduced graphene oxide for photocatalytic H2 evolution under visible light irradiation

A novel heterogeneous hybrid composed of Nb₂O₅ microspheres and reduced graphene oxide as photocatalyst exhibits superior photocatalytic activity and stability.

Photocatalytic Water Splitting for Hydrogen Production with Gd₂MSbO₇ (M = Fe, In, Y) Photocatalysts under Visible Light Irradiation

Novel photocatalysts Gd₂FeSbO₇, Gd₂InSbO₇ and Gd₂YSbO₇ were synthesized by the solid state reaction method for the first time. A comparative study about the structural and photocatalytic properties of Gd₂MSbO₇ (M = Fe, In, Y) was reported. The results showed that Gd₂FeSbO₇, Gd₂InSbO₇ and Gd₂YSbO₇ crystallized with the pyrochlore-type structure, cubic crystal system and space group Fd3m. The lattice parameter a for Gd₂FeSbO₇, Gd₂InSbO₇ or Gd₂YSbO₇ was 10.276026 Å, 10.449546 Å or 10.653651 Å. The band gap of Gd₂FeSbO₇, Gd₂InSbO₇ or Gd₂YSbO₇ was estimated to be 2.151 eV, 2.897 eV or 2.396 eV. For the photocatalytic water-splitting reaction, H₂ or O₂ evolution was observed from pure water with Gd₂FeSbO₇, Gd₂InSbO₇ or Gd₂YSbO₇ as catalyst under visible light irradiation (wavelength > 420 nm). Moreover, H₂ or O₂ also spilt by using Gd₂FeSbO₇, Gd₂InSbO₇ or Gd₂YSbO₇ as catalyst from CH₃OH/H₂O or AgNO₃/H₂O solutions under visible light irradiation (λ > 420 nm). Gd₂FeSbO₇ showed the highest activity compared with Gd₂InSbO₇ or Gd₂YSbO₇. At the same time, Gd₂InSbO₇ showed higher activity compared with Gd₂YSbO₇. The photocatalytic activities were further improved under visible light irradiation with Gd₂FeSbO₇, Gd₂InSbO₇ or Gd₂YSbO₇ being loaded by Pt, NiO or RuO₂. The effect of Pt was better than that of NiO or RuO₂ for improving the photocatalytic activity of Gd₂FeSbO₇, Gd₂InSbO₇ or Gd₂YSbO₇.