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BiVO4, a narrow bandgap material (2.5 eV), has been widely explored for photocatalytic applications, but its applications in the optoelectronic field are unexplored. This work explores BiVO4 for photovoltaic devices using the oxygen vacancies mediated co‐sputtered Ti‐doped BiVO4 (Ti:BiVO4) that exhibits on‐site power production by photovoltaics and see‐through features. The structural, chemical, and optical properties of Ti:BiVO4 are investigated for heterojunction formation with p‐type NiO film. The sputtering power of Ti plays a significant role in improving the light absorption capability by increasing oxygen vacancy concentration, enhancing the device performance. The devices show an open‐circuit voltage value of 676 mV and a short‐circuit current density value of 4.83 mA cm−2 with a maximum power production value of 122.2 µW under UV illumination of intensity 53.1 mW cm−2. The obtained device performances correlate with the Ti dopant's deposition power that tunes the structural and optical properties of BiVO4 films. Moreover, in self‐powered mode, the fabricated devices show a fast photoresponse speed of 0.8 ms with a high detectivity value of 2.22 × 1012 Jones. This work establishes the suitability of co‐sputtered Ti:BiVO4 for the next generation of transparent self‐powered optoelectronic devices. [ABSTRACT FROM AUTHOR]

Cellulose acetate membrane has been applied to reverse osmosis for desalination due to chlorine tolerance and biofouling resistance. Since it requires optimized synthesis condition for application, we investigated the effect of different conditions on membrane performances. It was found that polymer concentration, solvent ratio, and evaporation time were critical to determine membrane selectivity and permeability. Based on the study, optimized conditions were obtained, which were 14 wt% of polymer concentration, 1:2.9 of ratio of 1,4-dioxane to acetone, and 30 s of evaporation time. Further, functionalized multi-walled carbon nanotubes (MWCNTs) were applied to the optimized bare membrane in order to enhance the performances. The composite membranes were characterized by fourier transform infrared spectroscopy, scanning electron microscopy, and contact angle measurement. It was found that the MWCNTs influenced the morphology and surface chemistry of the membrane. This study could contribute to develop a commercial composite RO membrane with nanomaterial for desalination application. [ABSTRACT FROM PUBLISHER]

Abstract For osmotic power generation using the pressure retarded osmosis (PRO) process, mechanically robust membranes with high osmotic water flux are needed to obtain high power density from a given osmotic pressure difference. Particularly in the case of support-free hollow fiber membranes (HFMs), the pressure tolerance is a critical factor in maximizing power density when operating at high applied pressure with concentrated brine. Here, mechanically robust integrally-skinned asymmetric (ISA) HFMs were developed by combining the nonsolvent induced phase separation (NIPS) with the quenching, into a facile approach called the thermally assisted NIPS (T-NIPS) method, to tailor the membrane structure for PRO applications. The prepared T-NIPS membranes exhibited two distinct layers: a dense ISA outer layer and an isoporous inner layer. Compared to conventional NIPS HFMs, the T-NIPS HFMs showed much higher power density and collapse pressure, up to 5.5 W/m2 and 18 bar, respectively. The effect of pore forming agents on the membrane structure during the T-NIPS process, and on PRO performance, were studied. In addition, the power density and the pressure tolerance were further enhanced by optimizing the membrane dimensions and structure of the T-NIPS HFMs. Graphical abstract Image 1 Highlights • PRO hollow fiber membranes were prepared via the T-NIPS method. • A dense outer layer with selective skin and an isoporous inner layer were formed. • The T-NIPS based membranes showed higher pressure tolerance than NIPS membranes. • The addition of PEG improved power density without sacrificing pressure tolerance. [ABSTRACT FROM AUTHOR]