Alternatively, straightforward synthesis is preferred because of the following advantages: 1) simplifying the preparation process, 2) avoiding the usage of additional acid or base solutions
that may increase the waste release, 3) resisting the formation of lattice defects and skeleton fragments, and 4) favoring higher thermal stability than post-dealuminated counterparts. However,direct synthesis of high-silica MOR zeolites in early attempts was usually proceeded in the presence of additional additives (fluoride, zeolitic seed, benzene-1,2-diol chelate agent, etc.), and the actual SAR in the final solid was restricted to below 74.2 . To our knowledge, no MOR zeolite with higher SAR has been reported with a straightforward synthesis. Therefore, it is still very difficult to facilely control the SAR of MOR in a wide range for achieving the high-silica MOR zeolites.