Heping Li,Zhiqiang Ke,Jing Li,Lihong Xue,Youwei Yan
Pores and cracks are usually inevitable in the coatings fabricated by plasma spraying . Herein, thermal chemical reaction technique was developed as an effective low-temperature strategy for addressing this issue. Dense α-Al 2 O 3 /AlPO 4 coating was synthesized on the surface of the plasma sprayed Al 2 O 3 -based coating by thermal chemical reaction at 500 °C. The α-Al 2 O 3 /AlPO 4 composites permeated into the coating and effectively filled up the pores and cracks inside. The sealed coating showed a uniform and dense morphology. The hydrogen permeation rate of the sealed coating sharply decreased by a factor of 15, which further confirmed its significantly improved compactness. In addition, the coating exhibited good thermal shock resistance and bond strength after sealing. Considering its low-temperature heat treatment, facile fabrication process and wide applicability, thermal chemical reaction method can be potentially used as a cost-saving strategy for sealing plasma sprayed ceramic coatings .
Hydrogen separation and purification are key to widespread application of hydrogen energy. Hydrogen permeable membranes based on lanthanum tungstate (LWO) attract attention due to favorable mechanical strength and chemical stability. However, industrial application of LWO-based membranes has remained challenging because of modest hydrogen permeances. Here we report a novel graded porous supported symmetric (GPSS) LWO-based membrane with improved transport properties, gas exchange dynamics, and operational stability, boosting stable hydrogen flux by several times over previously reported state-of-the-art membranes.
危险品化学品经营许可证（带存储）