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The enhanced photocatalytic hydrogen evolution performance of g-C3N4–Co3O4 2D–1D Z-scheme heterojunctions was achieved by employing the cobalt ion redox and conductive polymers (polyaniline, PANi) for the first time. Specifically, a Co3O4 1D nanobelt acting as the Z-scheme heterostructure component could promote the separation of photo-excited charge carriers and increased the redox capacity, and the conductive PANi brought about the boosted transport efficiency of the charge carriers. Notably, cobalt ions were adopted as the intermediate of the electron transfer between two components for boosting the carrier transport and utilization efficiency. Consequently, the Co3O4 nanobelt, PANi and cobalt ions exhibited a synergistic effect on facilitating the photocatalytic HER performance of the g-C3N4-based heterostructure, and the optimal ternary heterostructure (g-C3N4–PANi–Co3O4) exhibited a photocatalytic H2-evolution rate of 4.61 μmol h−1 under visible light, which further increased to 9.95 μmol h−1 by adding Co2+ solution owing to the further facilitated transport of charge carriers through the redox reaction of cobalt ions. Moreover, even in the absence of sacrificial agents, this Z-scheme system exhibited a photocatalytic hydrogen production activity of 3.35 μmol h−1 in the Co2+ aqueous solution under UV-visible light.

The phosphomolybdic acid hydrate (PMo12)-based g-C3N4-PANI-MoS2 with the conductive polyaniline mediator and the nanosized MoS2 cocatalyst were designed and in situ fabricated onto earth-abundant a...

A highly porous ternary TiO2/Co3O4/Ni photocatalyst is successfully constructed from a hetero-metal organic framework (H-MOF) template and via a facile photoreduction method. The photocatalytic H2 production coupled with the formation of H2O2 on TiO2 is improved by co-loading an oxidation promoter (Co3O4) and a reduction promoter (Ni) owing to the following factors: porous Co3O4 promotes the optical-response ability and surface water oxidation kinetics of TiO2, and in situ photo-deposited Ni facilitates the transport and utilization efficiency of photo-excited electrons. Owing to the synergy of the improved specific surface area and improved separation as well as utilization of photogenerated charge carriers, the optimal ternary TiO2/5at%Co3O4/0.5at%Ni heterostructure exhibits a hydrogen production activity 8.7 times higher than that of pure TiO2, and demonstrates obvious photocatalytic hydrogen evolution even in pure water, with stoichiometric H2O2 production. This work will provide insights into the design and synthesis of noble metal-free dual cocatalyst systems for efficient charge separation and transfer.

In order to further study the relationship between sorption properties of ZrCoCe thin films and magnetron sputtering process parameters, ZrCoCe getter films were deposited on the Si(100) substrate by DC magnetron sputtering. In this paper, background vacuum, sputtering pressure and sputtering power as experimental variables were discussed in detail. The surface and cross section microstructure and phase of the film were determined by scanning electron microscopy (SEM) and H2 sorption measurement of films was carried out by a dynamic sorption method. It is demonstrated that porous columnar structure film can be achieved under the conditions of the background degree less than 5.0×10-4 Pa, sputtering pressure is 4 Pa and sputtering power is 120 W. As a result of the optimization of the porous columnar structure, the sorption properties of the films are also improved.

A visible light-driven cadmium-free ZnS/rGO/CuS porous photocatalyst heterojunction was synthesized by simple hydrothermal and cation exchange methods using a zeolitic imidazolate framework (ZIF-8) as the template and Zn precursor. Due to the ZIF-8 templated high porous microstructure and/or the high carrier conductivity of the graphene (rGO), ZnS/CuS and ZnS/rGO/CuS heterojunctions exhibited a photocatalytic H2-production activity 9 and 13 times larger than that of the counterpoint heterojunction derived from the inorganic precursors under visible light irradiation, respectively. This work will provide an insight into the design and synthesis of ternary composite photocatalyts with high porosity and efficient charge separation and transfer.

Nickel coated Zr-V-Fe non-evaporable getter (NEG) powders were prepared using electroless plating. The microstructure and composition of the Ni-coated Zr-V-Fe powders were analyzed by XRD, SEM and EDS. The hydrogen absorption performance of Ni-coated Zr-V-Fe powders and as-prepared powders were analyzed by dynamic method after an activation at 300°C for 2 hours. The hydrogen absorption performance of Ni-coated Zr-V-Fe powders and as-prepared powders at 100°C, 200°C, 300°C, 400°C, and 500°C were also analyzed. The results indicated that Ni existed as crystalline phase. The Ni coating played an important role as a catalyst which favored the dissociation of hydrogen on surface and Ni lowers the hydrogen diffusion energy for the Zr-V-Fe powders. The hydrogen absorption kinetics of Ni-coated Zr-V-Fe powders was improved in comparison with that of the as-prepared powders, and a relatively higher absorption rate was exhibited.

Statistical experimental design strategy (SES) was employed to optimize the culture conditions for the mycelial growth of C. militaris by submerged culture. Using Plackett-Burman design (PBD), liquid volumes in flask and fermentation time were identified as the significant variables that would highly influence mycelial growth, and these variables were subsequently optimized using response surface method (RSM). The steepest ascent method was used to access the optimal region of the culture condition. The results showed that the optimum values of the tested variables were 47.3 mL of liquid volumes in flask and 7.6 days of fermentation time. Under optimized culture conditions, the mycelial production was enhanced from 10.33 to 19.97 g/L. In comparison with that of original culture conditions, 1.9-fold increase was obtained. The validation experiment showed that the experimentally determined production values were in close agreement with the statistically predicted ones.