Performance of rGO/TiO2 Photocatalytic Membranes for Hydrogen Production

Abstract

Although there are promising environmental and energy characteristics for the photocatalytic production of hydrogen, two main drawbacks must be overcome before the large- scale deployment of the technology becomes a reality, (i) the low efficiency reported by state of the art photocatalysts and, (ii) the short life time and difficult recovery of the photocatalyst, issues that need research and development for new high performance catalysts. In this work 2% rGO/TiO2 composite photocatalysts were supported over Nafion membranes and the performance of the photocatalytic membrane was tested for hydrogen production from a 20% vol. methanol solution. Immobilization of the composite on Nafion membranes followed three different simple methods which preserve the photocatalyst structure: solvent-casting (SC), spraying (SP), and dip-coating (DP). The photocatalyst was included in the matrix membrane using the SC method, while it was located on the membrane surface in the SP and DP membranes showing less mass transfer limitations. The performance of the synthesized photocatalytic membranes for hydrogen production under UVA light irradiation was compared. Leaching of the catalytic membranes was tested by measuring the turbidity of the solution. With respect to catalyst leaching, both the SC and SP membranes provided very good results, the leaching being lower with the SC membrane. The best results in terms of initial hydrogen production rate (HPR) were obtained with the SP and DP membrane. The SP was selected as the most suitable method for photocatalytic hydrogen production due to the high HPR and the negligible photocatalyst leaching. Moreover, the stability of this membrane was studied for longer operation times. This work helps to improve the knowledge on the application of photocatalytic membranes for hydrogen production and contributes in facilitating the large-scale application of this process.

Prospects of Synthesized Magnetic TiO2-Based Membranes for Wastewater Treatment: A Review

“…TiO 2 was then successfully deposited onto the functionalized membrane surface [82,105]. Some researchers have investigated the photocatalytic behavior of TiO 2 nanoparticles photografted onto commercial polymer membranes, such as polyester membranes [24,82,108,110]. Dong et al [98] used the activation reaction to coat TiO 2 nanotubes on a polyurethane (PU) membrane surface.…”

“…Polymer membranes are one of the most popular membranes used in wastewater treatment and water purification (Table 4). Polymers reported as support membranes of photocatalysts include polyamide, polyvinylidene fluoride (PVDF) [23], polyethersulfone (PES), poly (vinylidene fluoride) (PVDF) [24], sulfonated polyethersulfone (SPES), poly (vinylidene fluoride) [105][106][107][108], polyurethane (PU) [98], polyethylene terephthalate (PET) [82], polyester [58], polyacrylonitrile (PAN) [43] and polytetrafluoroethylene (PTFE) [109][110][111][112][113][114]. Polymer-inorganic nanoparticle composite membranes can be divided into two groups based on their structure: (a) polymer and inorganic phases linked by covalent bonds, and (b) polymer and inorganic phases linked by van der Waals forces or hydrogen bonds [113].…”

Past, Present and Future of Membrane Technology in Spain

“…The size growth of the research groups on membrane science and development has led to the subdivision of the former departments into subgroups specialized in a certain approach of membrane research and the type of publications and journals their members divulgate their results on, belonging to a wide range of applications and membrane materials and module fabrication methods. See, for instance in the directory, the IEC and PROMETEO groups of the Polytechnic University of Valencia, distinguish themselves between electrochemical applications and membrane processes for water treatment [62][63][64], the subgroups of the GIQA group at Rey Juan Carlos University, one devoted to polymeric membranes for wastewater treatment, the other on inorganic membranes for gas separation [65][66][67], or the division of the Chemical and Biomolecular Engineering Department at the University of Cantabria into four subgroups covering almost all the membrane topics [68][69][70][71][72][73][74][75][76]. Likewise, the CREG group at the University of Zaragoza has been divided by the results obtained in the later years in two subgroups, one devoted to membrane reactors and inorganic membranes, and the other on the synthesis and characterization of mixed matrix membranes for molecular separations [77][78][79], while the consolidation of membranes in health issues such as bone regeneration, grows in groups similar to that from the University of Seville here [80][81][82].…”

MXene potassium titanate nanowire/sulfonated polyether ether ketone (SPEEK) hybrid composite proton exchange membrane for photocatalytic water splitting

“…Thus, making this hybrid composite PEM as a photocatalytic active membrane that produces H 2 from water without the addition of any noble metals as co-catalysts in the same way as that of the photocatalytic membranes prepared by immobilizing rGO/TiO 2 into Naon membranes. 41 The membranes before and aer H 2 evolution testing under UV irradiation were characterized by XPS wide scan and core level high resolution. Fig.…”