Sulfuric acid (SA) decomposition is one of the key reactions in the sulfur-iodine (SI) cycle to produce hydrogen. Catalysts for the SA decomposition should be active and stable in a wide temperature range of 550–850 °C to absorb latent heat generated from a thermal solar heat or a very high temperature nuclear reactor. Here, mesoporous mSiC-15 is prepared using the SBA-15 template. TEM analysis shows that the morphology of the mSiC-15 has the replica structure of SBA-15. Pt/SBA-15 and Pt/mSiC-15 catalysts are prepared by impregnation and the catalytic activity is examined under the reaction condition of 650–850 °C and a GHSV of 76,000 mL/g_cat/h. The Pt/mSiC-15 catalyst is relatively stable for 50 h at 850 °C, while the Pt/SBA-15 was severely deactivated. The Pt amounts on the Pt/SBA-15 and Pt/mSiC-15 catalysts decreased from 0.73 and 0.80 wt% at initial reaction time to 0.39 and 0.68 wt% after 12 h reaction, respectively. The Pt loss during the SA reaction is main cause of deactivation, which is caused by the evaporation of Pt oxides under O₂ environment produced during the SA decomposition. It is observed that the Pt particles are embedded in porous SiO₂ (Pt/mSiO₂), which is transformed from Pt/mSiC-15 during the SA decomposition for 6 h. The Pt/mSiC-15 was relatively active and stable for the SA decomposition and the Pt loss was minimized by the structural change from Pt/mSiC-15 to Pt/mSiO₂ after 6 h.

硫酸（SA）分解是硫碘（SI）循环中产生氢的关键反应之一。用于SA分解的催化剂应在550-850°C的宽温度范围内保持活性且稳定，以吸收太阳热或高温核反应堆产生的潜热。在此，使用SBA-15模板制备了介孔mSiC-15。TEM分析表明，mSiC-15的形态具有SBA-15的复制结构。通过浸渍制备Pt / SBA-15和Pt / mSiC-15催化剂，并在650–850°C和GHSV为76,000 mL / g _cat的反应条件下检查催化活性。/H。Pt / mSiC-15催化剂在850°C下相对稳定50小时，而Pt / SBA-15则严重失活。Pt / SBA-15和Pt / mSiC-15催化剂上的Pt量分别从初始反应时间的0.73和0.80 wt％降低到12 h反应后的0.39和0.68 wt％。SA反应期间的Pt损失是失活的主要原因，这是由于在SA分解过程中在O ₂环境下Pt氧化物的蒸发引起的。观察到，Pt颗粒嵌入多孔SiO ₂（Pt / mSiO ₂）中，在SA分解6 h时，其从Pt / mSiC-15转变。Pt / mSiC-15对SA分解相对活跃且稳定，并且通过从Pt / mSiC-15到Pt / mSiO的结构变化将Pt损失最小化₂后6小时。