RESUMEN
Solar water splitting has gained increasing attention in converting solar energy into green hydrogen energy. However, the construction of a photothermo-electro coupling field by harnessing light-induced heat and its enhancement on solar water splitting were seldom studied. Herein, we developed a full-spectrum responsive photoanode by depositing CdxZn1-xS onto the surface of hydrogenated TiO2 nanotube array (H-TNA), followed by modification with Ni2P. The resulting ternary photoanode exhibits a photocurrent density of 4.99 mA·cm-2 at 1.23 V vs. RHE with photoinduced heating, which is 11.9-fold higher than that of pristine TNA, with an optimal ABPE of 2.47%. The characterization results demonstrate that the ternary photoanode possesses superior full-spectrum absorption and efficient photogenerated carrier separation driven by the interface electric fields. Additionally, Ni2P reduces the hole injection barrier and increases surface active sites, accelerating the consumption of holes accumulating on the relatively unstable CdxZn1-xS to simultaneously improve the activity and stability of water splitting. Moreover, temperature-dependent measurements reveal that H-TNA and Ni2P significantly motivate the photothermal conversion to construct a photothermo-electro coupling field, optimizing photoelectric conversion and charge carrier-induced surface reactions. This work contributes to understanding the synergistic effect of the photothermo-electro coupling field on the photoelectrochemical water splitting.
RESUMEN
Photocatalytic CO2reduction is considered to be an appealing way of alleviating environmental pollution and energy shortages simultaneously under mild condition. However, the activity is greatly limited by the poor separation of the photogenerated carriers. Ion doping is a feasible strategy to facilitate the charge transfer. In this work, Ni-doped Bi4O5I2photocatalyst is successfully fabricated using a one-pot hydrothermal method. A few doping levels appear in the energy band of Bi4O5I2after Ni doping, which are used as springboards for electrons transition, thus promoting photoexcited electrons and holes separation. As a consequence, a remarkably enhanced yield of CO and CH4(6.2 and 1.9µmol g-1h-1) is obtained over the optimized Bi4O5I2-Ni15, which is approximately 2.1 and 3.8 times superior to pure Bi4O5I2, respectively. This work may serve as a model for the subsequent research of Bi-based photocatalysts to implement high-performance CO2photoreduction.
RESUMEN
Constructing a p-n heterojunction has been regarded as an effective way to restrain charge recombination and boost photocatalytic H2 production activity. Herein, a novel Mn0.2Cd0.8S/NiWO4 composite was fabricated by a hydrothermal process and which exhibited enhanced H2 production activity and excellent photostability. Particularly, the composite with 30 wt% of NiWO4 achieved the optimal H2 production rate of 17.76 mmol g-1 h-1, which was 2.9 times higher than that of Mn0.2Cd0.8S. The increased H2 production property was mainly due to the p-n heterojunction between Mn0.2Cd0.8S and NiWO4, which provided an efficient path for charge transfer and inhibited the photocorrosion of Mn0.2Cd0.8S. This work can offer technical support for the design and development of p-n heterojunctions that can be applied for photocatalytic H2 production.
RESUMEN
A new 3-D open-framework cadmium borovanadate with 6-connected topology was hydrothermally obtained and structurally characterized. It not only features new cadmium(II) borovanadate which possesses an open-framework structure with unique plane-shaped channels, but also exhibits interesting absorption properties and high catalytic activities for the oxidation of cyclohexanol.
Asunto(s)
Compuestos de Boro/química , Cadmio/química , Ciclohexanoles/química , Ciclohexanonas/síntesis química , Vanadatos/química , Catálisis , Ciclohexanonas/química , Modelos Moleculares , Oxidación-ReducciónRESUMEN
A novel open-framework copper borophosphate, Na5KCu3[B9P6O33(OH)3]·H2O (), has been synthesised by a boric acid flux method. Its structure can be viewed as a 3-D open framework constructed by the connection of Cu(II)O6 octahedra and 1-D (4,4)-connected borophosphate anionic structures composed of trigonal-planar BO2(OH) groups, tetrahedral BO4 and PO4 groups. The compound not only features a novel borophosphate anionic partial structure containing 1-D 12-MR channels, but also exhibits ferromagnetic interactions and high catalytic activity for the oxidative degradation of chitosan.
Asunto(s)
Compuestos de Boro/química , Cobre/química , Compuestos Organometálicos/química , Fosfatos/química , Aniones/química , Ácidos Bóricos/química , Catálisis , Quitosano/química , Magnetismo , Conformación Molecular , Oxidación-Reducción , Temperatura , Difracción de Rayos XRESUMEN
In the title 1:1 adduct, C(10)H(10)O(4)·C(12)H(10)N(2), the two components are linked by O-Hâ¯N hydrogen bonds to form a one-dimensional chain. The dihedral angle between the pyridine rings is 15.68â (8)° These chains are further inter-connected by weak inter-molecular C-Hâ¯O hydrogen bonds and weak C-Hâ¯π inter-actions to generate a three-dimensional network.
RESUMEN
Chitosan was effectively degraded by hydrogen peroxide under irradiation with ultraviolet light. The existence of a synergetic effect on the degradation was demonstrated by means of viscometry. In addition, the optimal conditions of degradation were determined on the basis of orthogonal tests. The structure of the degraded product was characterized by Fourier-transform infrared spectra (FTIR) analysis and diffuse reflectance spectra (DRS) analysis. The mechanism of the degradation of chitosan was correlated with cleavage of the glycosidic bond.