Effect of Preparation Parameters on Photoactivity of BiVO₄by Hydrothermal Method

Bismuth vanadate (BiVO4) was synthesized from a mixture of aqueous Bi(NO3)3and NH4VO3solutions by using hydrothermal method. Via conducting the orthogonal experiments and single-factor experiments, the best synthetic parameters were determined. The physical and photophysical properties of the as-obtained samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-Vis diffusion reflectance spectroscopy (UV-Vis). The result showed that the best experimental parameters of monoclinic BiVO4werepH=7,T=195 °C, and  t=6 h. The catalytic performance of BiVO4was evaluated by reducing carbon dioxide to methane under visible light irradiation. It was found that the methane production reached 145 μg/g-cat after 5 h irradiation with the catalyst dosage of 0.15 g in 200 mL mixed solution of 0.1 M NaOH and 0.1 M Na2SO3.</jats:p

Polymer Photoelectrodes for Solar Fuel Production: Progress and Challenges

Converting solar energy to fuels has attracted substantial interest over the past decades because it has the potential to sustainably meet the increasing global energy demand. However, achieving this potential requires significant technological advances. Polymer photoelectrodes are composed of earth-abundant elements, e.g. carbon, nitrogen, oxygen, hydrogen, which promise to be more economically sustainable than their inorganic counterparts. Furthermore, the electronic structure of polymer photoelectrodes can be more easily tuned to fit the solar spectrum than inorganic counterparts, promising a feasible practical application. As a fast-moving area, in particular, over the past ten years, we have witnessed an explosion of reports on polymer materials, including photoelectrodes, cocatalysts, device architectures, and fundamental understanding experimentally and theoretically, all of which have been detailed in this review. Furthermore, the prospects of this field are discussed to highlight the future development of polymer photoelectrodes

Directional manipulation of diffusio-osmosis flow by design of solute-wall and solvent-wall interactions

Abstract Understanding of diffusio-osmosis, the flow induced by a solute gradient acting in narrow interfacial layers at a nanoscale solid-liquid interface, is of great value in view of the increasing importance of micro- and nano-fluidic devices and self-propelling particles. Using molecular dynamics simulations, we employ an appropriate strategy for direct simulation of diffusio-osmosis flows, mimicking a realistic experiment without any assumed external forces. It allows us to obtain reliable flow details, which are hard to obtain in experiments. We found that the solvent-wall interaction, previously overlooked in the classical paradigm, plays a critical role in the diffusio-osmosis process. In particular, diffusio-osmosis is controlled by the interaction difference between the solute-wall and solvent-wall. When the solute-wall interaction is stronger (weaker) than the solvent-wall, a surface excess (depletion) of solute particles on the solid-liquid interface is formed, which induces diffusio-osmosis flow towards a low (high) concentration. We modified the classical Derjaguin expression to include the effect of nanoscale hydrodynamics boundary conditions for the accurate prediction of diffusio-osmosis characteristics. Overall, our results provide clear guidance for controlling fluid flow and manipulating the motion of colloids under tunable solute concentrations.</jats:p