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The solar-driven CO2 reduction reaction (CO2RR) for producing chemical fuels is considered to be a promising approach to dealing with the growing energy crisis and greenhouse effect. Herein, novel Ag/MnOx dual-cocatalyst-decorated brookite titania (BT) nanoparticles with remarkably boosted photocatalytic CO2RR performance are prepared through a facile photodeposition method. The resultant xAg-BT-yMn composite with optimal cocatalyst content delivers amazing CO/CH4 yields of 31.70/129.98 μmol g-1 with an overall photoactivity of 1103.28 μmol g-1 h-1, 11.98 times higher than that of the BT nanoparticles alone. Further investigations demonstrate that the dual cocatalysts decorating the BT nanoparticles not only effectively retard the photoinduced charge recombination but also significantly vary the surface chemical feature to promote the adsorption/activation of the reactants (CO2/H2O). In addition, the Ag nanoparticles can broaden the spectral response region, while the MnOx cocatalyst can promote the CH4 product selectivity and the water oxidation reaction. The synergistic effect of Ag/MnOx dual cocatalysts on the BT nanoparticles renders a remarkably boosted CO2RR performance, which provides a simple yet general synthesis strategy for brookite titania-based photocatalysts with high-performance solar-driven CO2 conversion.

The solar-driven CO

A vertically oriented rutile TiO2 nanorod (NR) array, as an efficient electron transport layer (ETL), has been used in the perovskite solar cells (PSCs), and its microstructure has a great impact on the corresponding photovoltaic conversion efficiency (PCE). Here we employ a facile control strategy to modulate the microstructures of rutile TiO2 NR arrays hydrothermally grown on the fluorine tin oxide (FTO) glass from a water–HCl solution of titanium n-butoxide (TBOT). It was found that introducing commercial TiO2 nanoparticles (P25, Degussa) into the hydrothermal reaction system can efficiently slow down the growth rate of rutile TiO2 NRs, thus causing the controllable preparation of an NR array on the FTO substrate. The device fabricated with an optimized NR array derived from the hydrothermal reaction solution containing P25 exhibits an improvement of 26.5% in PCE compared with the device fabricated with the NR array from the hydrothermal solution without P25, which is mainly attributed to the reduced c...

Solar-driven CO2 reduction reaction (CO2RR) for producing chemical fuels over semiconductors is considered to be a potential way to ameliorate the global warming and energy shortage. Herein, we report a facile and robust method by co-decorating Pt/MnOx dual cocatalysts on sea-urchin-like anatase TiO2 microspheres (AMS) to significantly improve the CO2RR activity and CH4 product selectivity. The xPt-yMn-AMS composite with optimal contents of dual cocatalysts manifests compelling CO/CH4 yields of 16.5/125.3 μmol g−1h−1 with a total photoactivity of 1035.4 μmol g−1h−1, 13 times higher than that of AMS alone. The Pt nanoparticles on AMS mainly improve the photoexcited charge separation and CO2RR efficiency, while the MnOx cocatalyst mainly promotes the adsorption/activation of reactants and the CH4 product selectivity by varying the surface chemistry. The synergistic effect of dual cocatalysts on AMS renders the significantly improved CO2RR performance, and thus provides a simple yet general strategy for fabricating high-performing CO2RR TiO2-based photocatalyst.

Photocatalytic CO2 reduction to solar fuels is considered as a promising strategy to address the global warming and energy shortages. Herein, a novel method is proposed to prepare g-C3N4/ZnO nanocomposites via refluxing zinc salt methanol solution containing pre-formed g-C3N4 with KOH methanol solution as precipitating agent. Some in-situ grown ultrafine ZnO nanoparticles are decorated on ultrathin g-C3N4 layers with well-defined interface, which not only causes efficient charge transfer and separation, but also creates more active sites for CO2 adsorption and activation. The resultant g-C3N4/ZnO composites demonstrate significant enhanced CO2 photoreduction activity and selectivity for CH4 production under visible light irradiation, and the optimal g-C3N4/ZnO composite delivers the best overall photoactivity (158.4 μmol g−1 h−1) with CH4/CO production rates of 19.8/0.37 μmol g−1 h−1, which is 9.42 times higher than that of g-C3N4 alone. This work provides an ideal synthetic strategy for g-C3N4-based hybrid materials with highly efficient CO2 photoreduction.

A study was conducted to characterize the effects of dietary oxidized fish oil on the intestinal enzyme activities, morphology, microbiome composition of genetically improved farmed tilapia (Oreochromis niloticus) and to determine the role of ferulic acid on the intestinal oxidative damage induced by the oxidized fish oil and intestinal microbiota. The tilapia (13.73 ± 0.31 g) were fed four experimental diets containing untreated (peroxide value, POV: 2.2 meq kg−1) and highly oxidized (POV: 120.6 meq kg−1) fish oil either with or without ferulic acid (0 or 400 mg kg-1) supplementation for 12 weeks. From the results, the oxidized fish oil treatments increased antioxidant enzyme activities and MDA values in serum and intestine, but decreased the activities of digestive enzymes. In the oxidized fish oil-receiving groups, intestinal villus height and villus width were significantly reduced, and the muscular thickness was significantly increased in tilapia. Besides, the oxidized fish oil might cause the dysbiosis of intestinal microbiota. Meanwhile, the addition of ferulic acid partially counteracted the free radical-induced damage and improved the intestinal health of tilapia. In conclusion, the oxidized fish oil may induce oxidative stress, destroy the intestinal morphology, lower digestive capacity as well as disturb the stability of microbial community, whereas ferulic acid supplementation partially offset the negative effects of the oxidized fish oil on tilapia.

WO 3 with various morphologies and crystal phases were prepared via a hydrothermal process in the presence of different Na 2 SO 4 concentrations. Experimental results indicated that the preferred growth face ((200) crystal plane) of hexagonal WO 3 could adsorb abundant Na + , which induced the WO 3 growing along [001] crystal direction to form nanorods, and hexagonal phase WO 3 nanorods with diameter of 30–150 nm and length of 0.5–5 μm were obtained in the presence of 0.25 M Na 2 SO 4 , while excessive Na 2 SO 4 led to a mixed crystal consisting of cubic H 2 W 2 O 7 and hexagonal WO 3 . The photoactivities for O 2 evolution for various products were investigated by using Fe(NO 3 ) 3 as a sacrificial reagent under visible-light irradiation, and the hexagonal phase WO 3 nanorods show a better photoactivity than the other products with different morphologies and crystal phases due to its fast three-dimensional photogenerated carrier transfer along its special rod-shaped structure.

CdS/Rectorite nanocomposites were prepared through hydrothermal method by using Cd[NH2CSNH2]2Ac2 complex as precursor of CdS which was derived from cadmium acetate and thiourea. The obtained nanocomposites were characterized by X-ray diffraction (XRD), Fourier transfer infrared spectra (FTIR), diffusion reflection spectra (DRS), transmission electron microscopy (TEM) and the selected area electron diffraction (SAED) patterns. Experimental results indicate that CdS exist in at least three forms: CdS adsorbed at surface, CdS pillared in montmorillonite-like layers of Rectorite and CdS pillared in the new layered structure formed during the hydrothermal process. Those CdS crystals are hexagonal symmetry. The photoactivity and photostability of the obtained CdS/Rectorite nanocomposites are improved significantly compared to that of the reference Rectorite and pure CdS.

CdS/rectorite nanocomposite was synthesized via a cation-exchange reaction followed by a sulfurization process. The obtained samples were characterized by using X-ray diffraction (XRD), fourier transform infrared spectra (FTIR), transmission electron microscope (TEM), UV-Vis diffuse reflectance spectra (DRS), and thermal analysis. The measured results indicate that CdS species in the composites exist in the form of pillars and nanoparticles, the crystallized CdS particles are in the hexagonal symmetry. The photocatalytic activities of the pillared nanocomposite were enhanced significantly comparing with the bare rectorite and the pure CdS. Moreover, the photostabilities of the obtained nanocomposites are also better than that of the pure CdS due to the hosts retard the photocorrosion of the CdS.

Nd 3+ -doped titania nanoparticles with mesostructures were synthesized via hydrothermal process by using cetyltrimethylammonium bromide (CTAB) as directing and pore-forming agent. The obtained materials were characterized by XRD, nitrogen adsorption–desorption, TEM and DRS. The existence of neodymium ion affect significantly the phase transition of the amorphous to anatase, and the band-gap energy was reduced because of the defect energy level induced by the 4 f atomic orbital of Nd 3+ with the optimal content of 1.5 at.% Nd. Density functional theory calculations can explain the band-gap narrowing. The maximum photocatalytic activity corresponds to the 0.5 at.% Nd 3+ -doped anatase nanopowders with mesostructures, which is higher than that of undoped samples.

Titania was synthesized from laurylamine hydrochloride (LAHC) and Ti(SO 4 ) 2 under different acidic conditions. The effect of acidity on the structural and textural evolution of titania has been investigated by X-ray diffraction (XRD), nitrogen adsorption–desorption, transmission electron micrographs (TEM), FTIR spectroscopy and thermogravimetric analysis (TGA). With increasing the pH value in the initial mixture, the obtained samples transformed from nanoparticles with intra-particle mesostructures (pH 0.6 and 2.0) to nanoparticles with nonporous structure (pH 3.7), and finally to worm-like porous materials with inter-particle mesostructures (pH 4.2) resulted from the aggregates of nanoparticles. The obtained mesoporous nanoparticles (pH 0.6 and 2.0) have mean diameter of ca . 25 nm, and the pore size distributions are bimodal with fine intra-particle pores and larger inter-particle pores. The intra-particle mesostructure not only retard the growth of nanocrystallites, but also prevent phase transition of anatase to rutile at high temperature. The BET surface area of the TiO 2 calcined at 300 °C decreased from 212 to 74 m 2 /g with pH increasing from 0.6 to 4.2.

Cerium-doped mesoporous TiO2 nanoparticles with high surface area and thermal stable anatase wall were synthesized via hydrothermal process in a cetyltrimethylammonium bromide (CTAB)/Ti(SO4)2/Ce(NO3)4/H2O system. The obtained materials were characterized by XRD, FESEM, HRTEM, FTIR spectroscopy, nitrogen adsorption and DRS spectra. Experimental results indicated that the doping of cerium not only increased the surface area of mesoporous TiO2 nanoparticles, but also inhibited the mesopores collapse and the anatase-to-rutile phase transformation. Moreover, the undoped, doped anatase mesoporous nanoparticles exhibit higher photocatalytic activity than commercial photocatalyst (Degussa, P25), but the maximum photodegradation rate corresponds to the undoped mesoporous TiO2 nanoparticles. The lower photocatalytic activities of cerium-doped samples compared with undoped one may be ascribed to that the doped cerium partially blocks titania's surface sites available for the photodegradation and absorption of Rhodamine B (RB).