Fig. 5: Inelastic neutron scattering (INS) spectra for TaAlS-1(0.013/0.027/1) on the adsorption and catalytic conversion of methanol and proposed reaction mechanism.

All spectra shown here are difference spectra. Full spectra are shown in the SI. The INS spectra of reactant, intermediates and products were recorded and modelled via DFT calculations, allowing a full assignment of the spectral features. Where no error bars are visible these are smaller than the symbols used to represent the data points. Comparison of INS spectra obtained at TOSCA (a), at MAPS (b) at incident energy 250 meV over the momentum transfer range 0 Å⁻¹ ≤ Q ≤ 9 Å⁻¹ and, at MAPS (c) at incident energy 650 meV over the momentum transfer range 0 Å⁻¹ ≤ Q ≤ 9 Å⁻¹ for condensed solid methanol, adsorbed methanol, and reacted methanol on TaAlS-1(0.013/0.027/1). d Selected vibrational modes of methanol, DME, TMO and propene (C, grey; O, orange; H, white). Proposed reaction mechanism for the conversion of methanol in the induction period over e TaAlS-1 based on INS/SXPD experiments and f in the induction and dual-cycle period over HZSM-5 based on SXPD and literature reports^16,20.