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TiO2 has garnered a flourish of interest in the field of energy storage and energy conversion. Herein, a new generation of 3D Ni foam supported in situ grown 1D TiO2 nanoarray (Ni/TiO2) is successfully prepared, through an easy solution‐phase hydrothermal process, and then CdS nanorods branched Ni/TiO2 nanoarrays are fabricated (Ni/TiO2@CdS). Their formation parameters and growth mechanism are carefully studied. Both Ni/TiO2 and Ni/TiO2@CdS monolithic catalysts exhibit advantaged photocatalytic (PC) and photoelectrocatalytic (PEC) water splitting properties compared with that of most previously reported TiO2‐based film photocatalysts. Mechanism investigation reveals that both type II and Z‐scheme charge transport mechanisms coexist in Ni/TiO2@CdS sample, and an additional Z‐scheme charge transfer effect accelerates the photogenerated charge separation and transport efficiency. This study may open a new avenue for the utilization of TiO2‐based film catalysts in a broader field of energy and environmental catalysis areas. [ABSTRACT FROM AUTHOR]

The rational design and construction of cost‐effective nickel‐based phosphide or sulfide (photo)electrocatalysts for hydrogen production from water splitting has sparked a huge investigation surge in recent years. Whereas, nickel phosphides (NixPy) possess more than ten stoichiometric compositions with different crystalline. Constructing NixPy with well crystalline and revealing their intrinsic catalytic mechanism at atomic/molecular levels remains a great challenge. Herein, an easy‐to‐follow phase‐controllable phosphating strategy is first proposed to prepare well crystalline NixPy (Ni3P and Ni12P5) modified CdS@Ni3S2 heterojunction electrocatalysts. It is found that Ni3P modified CdS@Ni3S2 (CdS@Ni3S2/Ni3P) exhibits remarkable stability and bifunctional electrocatalytic activities in both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Density functional theory results suggest that P–Ni sites and P sites in CdS@Ni3S2/Ni3P, respectively, serve as OER and HER active sites during electrocatalytic water splitting processes. Moreover, benefiting from the advantageous photocatalyst@electrocatalyst core@shell structure, CdS@Ni3S2/Ni3P delivers an advantaged photoassisted electrocatalytic water splitting property. The champion electrical to hydrogen and solar to hydrogen energy conversion efficiencies of CdS@Ni3S2/Ni3P, respectively, reach 93.35% and 4.65%. This work will provide a general guidance for synergistically using solar energy and electric energy for large‐scale H2 production from water splitting. [ABSTRACT FROM AUTHOR]

Highly efficient and easy recyclable monolithic photocatalysts with ideal separation/transport route for photogenerated charge carriers are much desired. In this work, a ZnO seed‐induced growth approach is developed to fabricate a ternary monolithic photomembrane, that is, ZnS/CdS heterojunction nanorods in situ grow into the interspaces of multilayer reduced graphene oxide (rGO) sheets (denoted as ZnS/CdS/rGO). The monolithic ZnS/CdS/rGO photomembrane can serve as an efficient visible‐light photoactive membrane for photocatalytic (PC) or photoelectrochemical (PEC) hydrogen generation. The fast electron transport of 1D CdS nanorods, the excellent electronic conductivity of multilayer stacked rGO sheets, the intense visible‐light absorption of CdS, the unique hierarchical structure, and double heterojunctions (ZnS/CdS and CdS/rGO) efficiently boost the photogenerated electron‐hole pairs separation and transfer across the interfacial domain of the photomembrane under visible‐light irradiation. Furthermore, the superior stability and reusability of the photomembrane is achieved by the ideal process of photogenerated electron‐hole pair separation/transfer, i.e., holes transfer to ZnS and electrons transfer to rGO to inhibit CdS from photocorrosion. [ABSTRACT FROM AUTHOR]

In this work, the titanium dioxide () nanofilms co-doped with and ions were successfully fabricated by the sol-gel method with dip-coating process. Methylene blue was used as the target degradation chemical to study the photocatalytic properties affected by different doping contents of and ions. The samples were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and infrared (IR) spectroscopy. The results indicated that both pure nanofilms and single-doped samples possessed the photocatalytic activity in degradation of methylene blue. However, when the nanofilms co-doped with and ions were fabricated at the molar ratio of 3:1 (:), they exhibited the best photocatalytic activity after the heat treatment at C for 2h. The wettability property test indicated that the nanofilms co-doped with and ions in the molar ratio 3:1 owned an excellent hydrophilic property. [ABSTRACT FROM AUTHOR]

In the present work, the earth-abundant NiS co-catalyst modified mesoporous graphite-like C3N4 (mpg-C3N4)/CNT nanocomposites were prepared via a two-step strategy: the sol–gel method and the direct precipitation process. The mpg-C3N4/CNT/NiS composite photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis absorption spectroscopy, photoluminescence spectroscopy (PL), photoelectrochemical (PEC) and electrochemical impedance spectra (EIS) experiments. The photocatalytic H2-production activity over the composite catalysts was also evaluated by using an aqueous solution containing triethanolamine under visible light (λ≥ 420 nm). The results showed that the loading of earth-abundant NiS co-catalysts onto metal-free mpg-C3N4/CNT nanocomposites can remarkably enhance their photocatalytic H2-production activity. The optimal loading amount of NiS on metal-free mpg-C3N4/CNT nanocomposites was about 1 wt%. The as-obtained mpg-C3N4/CNT/1% NiS ternary composite photocatalyst exhibits the best H2-evolution activity with the highest rate of about 521 μmol g−1 h−1 under visible light (λ≥ 420 nm), which is almost 148 times that of a pure mpg-C3N4/CNT sample. The enhanced photocatalytic activity can be mainly attributed to the synergistic effect of effectively promoted separation of photo-generated electron–hole pairs and enhanced H2-evolution kinetics. The co-loading of nanocarbon materials and earth-abundant co-catalysts onto metal-free mpg-C3N4 photocatalysts offers great potential for practical applications in photocatalytic H2 evolution under visible light illumination. [ABSTRACT FROM AUTHOR]

Novel functional composite architectures, low-loading platinum (Pt) decorated aligned ZnO nanorods, have been synthesized by using a highly effective photochemical synthesis. X-ray diffraction, scanning electron microscope and transmission electron microscopy have been employed to characterize the samples. The analysis indicates that small Pt particles of about 3 nm in size are uniformly distributed on the surface of ZnO nanorods (about 60 nm in diameter). The as-prepared heterostructured Pt/ZnO catalyst shows the desirable activity for the photocatalytic degradation of Methyl Orange dye as well as electrocatalytic methanol oxidation. The findings suggest that this novel composite architecture could be used as a bi-functional catalyst for photocatalytic and electrocatalytic applications. [ABSTRACT FROM AUTHOR]

Novel SnO2/SiC hollow sphere nanochains were synthesized by topological morphology conversion of SnO2@C core–shell nanochains through a vapour–solid reaction. Evaluation of the SnO2/SiC HSNCs for the generation of hydrogen revealed that they exhibit excellent catalytic activity and durability. [ABSTRACT FROM AUTHOR]

Novel carbon nitride polymer sensitized TiO2nanotube arrays with high photocatalytic activity and photoelectrochemical response under visible light irradiation are prepared by electrodeposition. [ABSTRACT FROM AUTHOR]

Coating a protective agent or promoter on the surface of the photocatalyst is a proven good strategy to realize photocatalytic hydrogen production from pure water, but remains still a considerable challenge. Herein, a novel CdS@Mg(OH) 2 core/shell composite nanorods photocatalyst was synthesized by coating Mg(OH) 2 on CdS surface by hydrothermal and precipitation processes. The coated-Mg(OH) 2 layer did not change the structure of CdS, and the photocatalytic overall water splitting performance of the CdS@Mg(OH) 2 under visible light irradiation was improved obviously. After loading nano-Pt via the photodeposited method, the hydrogen production rate and stability of Pt/CdS@Mg(OH) 2 were 3.3 and 2.4 times that of the Pt/CdS under the visible light irradiation, respectively. The surface Mg(OH) 2 layer improved the hydrophilicity and stability of the core/shell composites and increased the amount of active sites, thus improving the photocatalytic properties. It is believed that Mg(OH) 2 can be used as a new co-catalyst to enhance the performance of photocatalytic overall water splitting. [Display omitted] • CdS@Mg(OH) 2 core/shell composite nanorods photocatalyst was synthesized. • The Mg (OH) 2 layer improves the hydrophilicity, stability and active sites of the CdS nanorods. • The CdS@Mg(OH) 2 exhibites efficient visible-light photocatalytic overall water splitting. • The CdS@Mg(OH) 2 shows excellent stability and reusability. [ABSTRACT FROM AUTHOR]

A novel Co 3 O 4 /BiOBr catalyst with p-n heterojunction structure (COBB) is fabricated by loading p-type Co 3 O 4 nanoparticles on n -type BiOBr nanosheets, and used as a photocatalyst for efficient degradation of glyphosate driven by sunlight. [Display omitted] • A p-n heterojunction photocatalyst of Co 3 O 4 loaded BiOBr nanosheets (COBB) is reported. • Built-in electric field in COBB inhibits recombination of photogenerated e--h+ pairs. • Only 1.3 % of COBB photocatalytic activity for degrading glyphosate is lost after 4 cycles. The environmental stresses posed by glyphosate, an organic phosphorus herbicide with inert C P and C N bonds, necessitate its effective degradation. Herein, we present a novel p-type Co 3 O 4 / n -type BiOBr heterojunction (COBB) photocatalyst as an efficient solution for this challenge. Owing to the built-in electric field as well as the synergistic matching band potentials of the p-Co 3 O 4 and n -BiOBr, the COBB considerably enhances the separation efficiency and transfer rates of photogenerated carriers. As a result, it displays remarkable activity in degrading 16.9 mg/L of glyphosate under simulated sunlight with 88.5 % efficiency, outperforming both the pure Co 3 O 4 and BiOBr by 51.8 and 3.3 times, respectively. In addition, COBB also demonstrates promising performance under natural sunlight and maintains a high level of stability in four cycles. Furthermore, intermediate product and toxicity analyses illustrate that the toxicity of glyphosate is greatly reduced in the COBB system. Altogether, this study provides renewed opportunities for the use of heterojunction photocatalysts in natural environments. [ABSTRACT FROM AUTHOR]

A simple and facile two-step method, including electrophoretic deposition and chemical bath deposition strategies, has been used to fabricate a novel interlocking g-C 3 N 4 /CdS photoanode on conductive substrate. Integrating a large area of intercontact g-C 3 N 4 /CdS heterojunction with an intimate connection between the photocatalysts and the substrate, the separation and migration of the photogenerated carriers by g-C 3 N 4 and CdS are significantly improved, and the internal resistance of the photoanode is effectively reduced. The optimal g-C 3 N 4 /CdS photoanode exhibits an excellent visible light photocurrent density of 5.4 mA cm -2  at 0.0 V bias ( vs. Ag/AgCl) and the photoelectrochemical H 2 production rate reaches 81.1 μmol h -1  cm -2 . Moreover, the stability of this interlocking g-C 3 N 4 /CdS photoanode not only reflects in a 9-hour long time recycling photoelectrochemical H 2 production test, but also in an outstanding steady structure which even be stabilized in an ultrasonic treatment. The present study provides a practical and convenient technique to develop such an earth abound and low-cost CdS/C 3 N 4 photoanode which can be used for high efficiency and stable photoelectrochemical solar energy conversion. [ABSTRACT FROM AUTHOR]

In recent years, tremendous efforts have been devoted to develop new photocatalyst with wide spectrum response for H 2 generation from water or aqueous solution. In this work, CdS nanoparticles (NPs) have been immobilized on hydrogenated three-dimensional (3D) branched TiO 2 nanorod arrays, resulting in a highly efficient photocatalyst, i.e, CdS/H-3D-TiO 2 . In addition, electrochemical reduction of H + ion is identified as a limiting step in the photocatalytic generation of H 2 at this catalyst, while here a Pt wired photocatalysis system (CdS/H-3D-TiO 2 /Pt-wire) is designed to overcome this barrier. Without the application of potential bias, visible light photocatalytic hydrogen production rate of CdS/H-3D-TiO 2 /Pt-wire is 18.42 μmol cm −2 h −1 , which is 11.2 times that of CdS/H-3D-TiO 2 without Pt (1.64 μmol cm −2 h −1 ). The Pt wire acts as an electron super highway between the FTO substrate and H + ions to evacuate the generated electrons to H + ions and catalyze the reduction reaction and consequently generate H 2 gas. This work successfully offers a novel direction for dramatic improvement in H 2 generation efficiency in photocatalysis field. [ABSTRACT FROM AUTHOR]

The hierarchical Ag NPs with a bimodal size distribution were auto-decorated on the surface of rice-like N-TiO 2 (named h-Ag/N-TiO 2 ) by semiconductor-metal double excitation process under solar light irradiation. The photoinduced growth process of self-assembled h-Ag/N-TiO 2 and its photocatalytic mechanism of photo-splitting ethanol into hydrogen have been discussed in detail. The synthesized h-Ag/N-TiO 2 as a plasmonic photocatalyst for photo-splitting ethanol exhibited a higher hydrogen production rate (4.7 mmol h −1 g −1 ) than Ag NPs universally loaded N-TiO 2 (3.4 mmol h −1 g −1 ) and pure N-TiO 2 (2.1 mmol h −1 g −1 ). This work presents a reversed photo-induced synthesis strategy to design a stable Ag-TiO 2 plasmonic photocatalyst with high photocatalytic efficiency under solar light. A better understanding of this solar light induced self-assembled process for Ag-TiO 2 is crucial in developing metal-semiconductor system for solar energy materials. [ABSTRACT FROM AUTHOR]

In this study, a novel efficient photocatalytic nanomaterial, TiO 2 nanocrystals supported on graphene-like bamboo charcoal, has been successfully synthesized via a facile multi-step process. The structural and optical properties of the as-prepared samples were characterized by different techniques, such as X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–vis absorption spectroscopy, photoluminescence spectra (PL), Raman spectra and nitrogen adsorption–desorption isotherms. The photocatalytic activities under sunlight were evaluated by the degradation of methylene blue (MB). The results indicated that the ternary hybrid photocatalysts exhibited much higher photocatalytic activities toward the degradation of MB than the pure TiO 2 under UV light irradiation. Moreover, the optimum weight content of graphene-like bamboo charcoal in composite photocatalysts was 6 wt% for achieving the maximum photocatalytic degradation rate. The apparent rate constant of the best sample (0.0509 min −1 ) was about 3 times greater than that of the commercial P25 (0.0170 min −1 ). The adsorption and degradation kinetics of MB can be described by the pseudo-first-order model and apparent first-order kinetics model, respectively. The highly enhanced photocatalytic performance was attributed to the synergetic effect of graphene-like carbon and bamboo charcoal, which lead to the promoted charge separation and reduction reaction of oxygen, and enhanced adsorption capacities of MB, respectively. The composite photocatalysts displayed a high photochemical stability under repeated irradiation. This work may provide new insights and understanding on the graphene-like bamboo charcoal as an excellent support for photocatalyst nanoparticles to enhance their visible-light photocatalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the electrodeposition potential on the morphology of Cu2O/TiO2 nanotube arrays (Cu2O/TNA) and their visible-light-driven photocatalytic activity for hydrogen evolution have been investigated for the first time in this work. The photocatalytic hydrogen evolution rate of the as-prepared Cu2O/TNA at the deposition potential of −0.8 V was about 42.4 times that of the pure TNA under visible light irradiation. This work demonstrated a feasible and simple electrodeposition method to fabricate an effective and recyclable visible-light-driven photocatalyst for hydrogen evolution. [Copyright &y& Elsevier]

Abstract: Cu(OH)2/TNAs photocatalyst was prepared by loading Cu(OH)2 nanoparticles on TiO2 nanotube arrays (TNAs) using a chemical bath deposition method. The amount of Cu(OH)2 loaded on the arrays was controlled by the repeated deposition times. The prepared catalyst was used to generate hydrogen under simulated solar light irradiation, and the results demonstrated that the hydrogen yield of Cu(OH)2/TNAs was 20.3 times that of the pure TNAs. Furthermore, the photocatalytic efficiency for hydrogen production decreased only 5.8% after five cycles, indicating that Cu(OH)2/TNAs photocatalyst showed excellent stability and reusability. This work presents an applicable and facile method to fabricate a highly active and stable photocatalyst for hydrogen production. [Copyright &y& Elsevier]

Abstract: A facile approach for the preparation of Fe3O4/g-C3N4 nanospheres with good porous structure has been demonstrated by a hydrothermal method. The as-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), ultraviolet–visible light (UV–vis) absorbance spectra and X-ray photoelectron spectroscopy (XPS). The photocatalytic decomposition of methyl orange (MO) by the as-prepared samples was carried out under visible light irradiation. The reusability and magnetic properties were also investigated. The results revealed that the porous Fe3O4/g-C3N4 nanospheres showed considerable photocatalytic activity, and exhibited excellent reusability and magnetic properties with almost no change after five runs. [Copyright &y& Elsevier]

Abstract: TiO2 nanotubes (TNTs) photocatalyst was synthesized by hydrothermal reaction, while the heterostructure CdS(or Bi2S3)/TiO2 nanotube photocatalysts were prepared by direct precipitation reaction. The photocatalysts were studied by TEM, EDX, XRD and XPS to characterize its structure and chemical compostion. Their photocatalytic activities for reducing CO2 to CH3OH under visible light irradiation and the performance for CO2 adsorption were also investigated. The results indicate that the synthetical TNTs photocatalyst is almost in good and uniform shapes, with the diameter of 17.77nm and the surface area of 99.57m2/g. The amounts adsorbed of CO2 on TNTs are 0.269mmol/g at 1atm pressure and 298K,which are larger than those on other two heterostructure photocatalysts. The adsorption isotherms of CO2 on three photocatalysts can be well described by the Freundlich adsorption equation. The modification of Bi2S3 or CdS can enhance the visible light absorbance and photocatalytic performance of TNTs photocatalyst. The photocatalytic activity, the amounts adsorbed of CO2 and visible light absorption capability of Bi2S3-modified TNTs photocatalyst are all better than those of CdS-modified TNTs photocatalyst. Especially, the largest yield of methanol on TNTs photocatalyst modified by Bi2S3 under visible light irradiation over 5h is 224.6μmol/g, which was about 2.2 times as large as that of TNTs. [Copyright &y& Elsevier]

Phosphorus-doped graphitic-C3N4 nanosheets coupled with BiPO4 nanorods are hydrothermally synthesized from aqueous solutions containing CH2N2, NaH2PO4, Bi(NO3)3, and HNO3 (autoclave, 483 K, 4 h), followed by calcination at 823 K for 4 h. [ABSTRACT FROM AUTHOR]