Design of in situ Solid-State NMR Rotor Inserts and Their Application to Catalytic Reactions

doi:10.11938/cjmr20243118

Abstract

Abstract:

In situ solid-state nuclear magnetic resonance (NMR) serves as a powerful means to study catalytic reactions under operating conditions. Standard solid-state NMR rotors typically struggle to match the pressure and temperature of active reactions during sampling. Here, we introduce specialized inserts for commercial solid-state NMR rotors capable of withstanding pressures from atmospheric to 618.3 kPa and temperatures ranging from room temperature up to 433 K. With this innovative design, we examine the isomerization of dihydroxyacetone (DHA) on Sn-MFI zeolite catalyst using in situ ¹H MAS NMR, revealing the presence of a gem-diols-type intermediate during the transformation of DHA into glyceraldehyde.

Key words: solid-state NMR, in situ, NMR rotors, catalytic reactions, spectroscopic characterization

CLC Number:

O482.53

SHEN Xueyuan, WANG Ruichen, QI Guodong, XU Jun, DENG Feng. Design of in situ Solid-State NMR Rotor Inserts and Their Application to Catalytic Reactions[J]. Chinese Journal of Magnetic Resonance, 2025, 42(1): 13-21.

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插件	温度/K	压强/kPa	重量变化/%
插件	温度/K	压强/kPa	第1次测试	第2次测试	第3次测试
4 mm PTFE	393	198.6	0	0	-0.5
4 mm PEEK	433	618.3	0	-2.0	-0.5
7 mm PTFE	433	618.3	-0.3	-0.1	-0.5
7 mm PEEK	433	618.3	-0.5	-0.3	-0.3

T_Set/K	样品位置
	顶部		中部		底部
	δ/ppm	T_Real/K	δ/ppm	T_Real/K	δ/ppm	T_Real/K
300	-0.05	300.41	-0.07	301.11	-0.06	299.11
307	-0.26	308.84	-0.28	309.54	-0.23	305.94
314	-0.41	314.87	-0.42	315.17	-0.38	311.96
321	-0.55	320.49	-0.54	319.99	-0.48	315.98
327	-0.62	323.30	-0.61	322.80	-0.56	319.19

插件	转速/kHz	耐受温度	耐受压力	适用体系
4 mm PTFE	0~10	室温~393 K	常压~198.6 kPa	除¹³C和¹⁹F以外的其他原子核观测
7 mm PTFE	0~4	室温~433 K	常压~618.3 kPa	除¹³C和¹⁹F以外的其他原子核观测
4 mm PEEK	0~10	室温~433 K	常压~618.3 kPa	除¹H和¹³C以外的其他原子核观测
7 mm PEEK	0~4	室温~433 K	常压~618.3 kPa	除¹H和¹³C以外的其他原子核观测