当前位置: X-MOL 学术ACS Catal. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Controlling the Surface Reactivity of Titania via Electronic Tuning of Self-Assembled Monolayers
ACS Catalysis ( IF 11.3 ) Pub Date : 2017-11-08 00:00:00 , DOI: 10.1021/acscatal.7b02789
Lucas D. Ellis 1 , Ryan M. Trottier 1 , Charles B. Musgrave 1 , Daniel K. Schwartz 1 , J. Will Medlin 1
Affiliation  

Reactivity of molecular catalysts can be controlled by organic ligands that regulate the steric and electronic properties of catalyst sites. This level of control has generally been unavailable for heterogeneous catalysts. We show that self-assembled monolayers (SAMs) on titania with tunable electronic properties provided fine control over surface reactivity. Controlling the identity of substituents on benzylphosphonic acid SAMs modulated the near-surface electrostatics, enabling regulation of the dehydration activity of 1-propanol and 1-butanol over a wide range, with activities and selectivities of the optimal catalyst far exceeding those of uncoated TiO2. The dipole moment of the adsorbed phosphonate was strongly correlated to the dehydration activity; kinetic measurements and computational modeling indicated that the interfacial electric field altered the transition-state structure and energy. Coating catalysts with SAMs having controllable charge distributions may provide a general approach to heterogeneous catalyst design analogous to the variation of ligands in molecular catalysts.

中文翻译:

通过自组装单分子膜的电子调谐控制二氧化钛的表面反应性

分子催化剂的反应性可以通过调节催化剂位点的空间和电子性质的有机配体来控制。对于非均相催化剂,通常无法达到这种控制水平。我们显示二氧化钛上具有可调节电子性能的自组装单分子膜(SAMs)提供了对表面反应性的良好控制。通过控制苄基膦酸SAM上取代基的身份,可以调节近表面静电,从而可以在很宽的范围内调节1-丙醇和1-丁醇的脱水活性,最佳催化剂的活性和选择性远远超过未涂覆的TiO 2的活性和选择性。。吸附的膦酸酯的偶极矩与脱水活性密切相关。动力学测量和计算模型表明界面电场改变了过渡态结构和能量。具有可控制的电荷分布的SAM的涂布催化剂可以提供类似于分子催化剂中的配体变化的非均相催化剂设计的一般方法。
更新日期:2017-11-08
down
wechat
bug