Matheus Rossetto

In this work, the MOF HKUST-1 and a combination of HKUST-1 with graphene oxide (GO) were synthesized via a green ball milling (BM) method, and their carbon capture performance was evaluated under post-combustion scenarios. A significant increase was observed in both CO₂ capacity (5.37 mmol CO₂/g for the composite compared to 3.15 mmol CO₂/g for the pristine MOF) and water sorption capacity (49 wt% for the composite compared to 29 wt% for pristine HKUST-1). Multicomponent dynamic sorption experiments, including gravimetric cycling and breakthrough measurements, show improved performance stability of the composite under humid conditions, with sustained CO2 uptake over repeated cycles. These results indicate modified competitive adsorption behaviour in the presence of water.,A multi-technique experimental insight into the competitive adsorption behaviour of the system is then provided through in situ methods. Infrared and ¹³C NMR spectroscopy, together with adsorption measurements, offer complementary qualitative evidence of guest–host and guest–guest interactions under different environments.,Overall, this study demonstrates that a small level of GO incorporation via mechanochemical synthesis can modify the CO₂/H₂O competitive adsorption behaviour of HKUST-1 under relevant humid conditions, highlighting its potential for post-combustion CO₂ capture applications.

Hyperpolarization methods, which increase the sensitivity of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI), have the potential to expand the range of applications of these powerful analytical techniques and to enable the use of smaller and cheaper devices. The signal amplification by reversible exchange (SABRE) method is of particular interest because it is relatively low-cost, straight-forward to implement, produces high-levels of renewable signal enhancement, and can be interfaced with low-cost and portable NMR detectors. In this work, we demonstrate an in situ approach to SABRE hyperpolarization that can be achieved using a simple, commercially-available Earth’s field NMR detector to provide ¹H polarization levels of up to 3.3%. This corresponds to a signal enhancement over the Earth’s magnetic field by a factor of ε > 2 × 10⁸. The key benefit of our approach is that it can be used to directly probe the polarization transfer process at the heart of the SABRE technique. In particular, we demonstrate the use of in situ hyperpolarization to observe the activation of the SABRE catalyst, the build-up of signal in the polarization transfer field (PTF), the dependence of the hyperpolarization level on the strength of the PTF, and the rate of decay of the hyperpolarization in the ultra-low-field regime.