Temperature-programmed surface reactions (TPSR) can be used to understand reactions within ICCU-DRM. The following methods were reported by Tian et al. (DOI: 10.1126/sciadv.aav507):
“TPSRs were performed in an automated chemisorption flow analyzer (ChemBET PULSAR TPR/TPD, Quantachrome Instruments), and two separate programs were executed to characterize the prepared sorbent-catalyst. For program I, a small amount of the freshly calcined sorbent-catalyst (~50 mg) was placed in a quartz U-tube and heated to 1073 K at a rate of 10 K min−1 under a gas flow of 50 ml min−1 containing 5 volume % H2 (balance in N2). Upon cooling to 373 K under a N2 flow, the sample was heated to 1173 K at a rate of 10 K min−1 under a gas flow of 50 ml min−1 containing 5 volume % CH4 (balance in N2). After that, the sample was cooled to 373 K under a N2 flow and then heated to 1273 K at a rate of 10 K min−1 under a gas flow of 50 ml min−1 containing 20 volume % CO2 (balance in N2). For program II, another ~50 mg of the freshly calcined sorbent-catalyst was placed in a quartz U-tube. After H2-TPR, as described in the first heating procedure of program I, the sample was cooled to 373 K under a N2 flow and then directly heated to 1273 K at a rate of 10 K min−1 under a gas flow of 50 ml min−1 containing 20 volume % CO2 (balance in N2). During each heating period, the change in the thermal conductivity of the gas flow passing through the sample was continuously recorded using a chemisorption analyzer.”