Publications by authors named "J T Gittins"

Conductive layered metal-organic frameworks (MOFs) have demonstrated promising electrochemical performances as supercapacitor electrode materials. The well-defined chemical structures of these crystalline porous electrodes facilitate structure-performance studies; however, there is a fundamental lack in the molecular-level understanding of charge storage mechanisms in conductive layered MOFs. To address this, we employ solid-state nuclear magnetic resonance (NMR) spectroscopy to study ion adsorption in nickel 2,3,6,7,10,11-hexaiminotriphenylene, Ni(HITP).

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Emissions reduction and greenhouse gas removal from the atmosphere are both necessary to achieve net-zero emissions and limit climate change. There is thus a need for improved sorbents for the capture of carbon dioxide from the atmosphere, a process known as direct air capture. In particular, low-cost materials that can be regenerated at low temperatures would overcome the limitations of current technologies.

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Article Synopsis
  • Layered metal-organic frameworks (MOFs), particularly Cu(HHTP), show promise in supercapacitance applications, with performance influenced by the size of electrolyte ions.
  • Smaller tetraalkylammonium (TAA) cations provide better capacitive performance than larger ones, leading to more efficient energy storage in both positive and negative charging.
  • The study reveals that while charging, larger ions saturate Cu(HHTP) pores, causing unusual charging dynamics and involving solvent molecules, which enhances our understanding of ion behavior in MOF systems.
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Electroconductive metal-organic frameworks (MOFs) have emerged as high-performance electrode materials for supercapacitors, but the fundamental understanding of the underlying chemical processes is limited. Here, the electrochemical interface of Cu(HHTP) (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) with an organic electrolyte is investigated using a multiscale quantum-mechanics/molecular-mechanics (QM/MM) procedure and experimental electrochemical measurements. Our simulations reproduce the observed capacitance values and reveals the polarization phenomena of the nanoporous framework.

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Metal-organic frameworks (MOFs) are among the most promising materials for next-generation energy storage systems. However, the impact of particle morphology on the energy storage performances of these frameworks is poorly understood. To address this, here we use coordination modulation to synthesise three samples of the conductive MOF Cu(HHTP) (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) with distinct microstructures.

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