Corredor Juan, Perez-Peña Eduardo, Rivero Maria J, Ortiz Inmaculada
Department of Chemical and Biomolecular Engineering, ETSIIT, University of Cantabria, Avda. de los Castros s/n, 39005 Santander, Spain.
Membranes (Basel). 2020 Sep 1;10(9):218. doi: 10.3390/membranes10090218.
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/TiO 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.
尽管光催化制氢具有良好的环境和能源特性，但在该技术大规模应用成为现实之前，必须克服两个主要缺点：（i）现有光催化剂报道的效率较低；（ii）光催化剂寿命短且回收困难，这些问题需要研发新型高性能催化剂。在这项工作中，将2%的rGO/TiO复合光催化剂负载在Nafion膜上，并测试了该光催化膜从20%体积的甲醇溶液中制氢的性能。将复合材料固定在Nafion膜上采用了三种不同的简单方法，这些方法保留了光催化剂的结构：溶剂浇铸（SC）、喷涂（SP）和浸涂（DP）。使用SC方法将光催化剂包含在基质膜中，而在SP和DP膜中，光催化剂位于膜表面，传质限制较小。比较了合成的光催化膜在紫外光照射下制氢的性能。通过测量溶液的浊度来测试催化膜的浸出情况。关于催化剂浸出，SC膜和SP膜都提供了非常好的结果，SC膜的浸出率更低。在初始产氢速率（HPR）方面，SP膜和DP膜取得了最佳结果。由于HPR高且光催化剂浸出可忽略不计，SP被选为最适合光催化制氢的方法。此外，还研究了该膜在更长运行时间下的稳定性。这项工作有助于增进对光催化膜制氢应用的了解，并有助于推动该工艺的大规模应用。
