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Chalcogel represents a unique class of meso‐ to macroporous nanomaterials that offer applications in energy and environmental pursuits. Here, the synthesis of an ion‐exchangeable amorphous chalcogel using a nominal composition of K₂CoMo₂S₁₀(KCMS) at room temperature is reported. Synchrotron X‐ray pair distribution function (PDF), X‐ray absorption near‐edge structure (XANES), and extended X‐ray absorption fine structure (EXAFS) reveal a plausible local structure of KCMS gel consisting of Mo⁵⁺₂and Mo⁴⁺₃clusters in the vicinity of di/polysulfides which are covalently linked by Co²⁺ions. The ionically bound K⁺ions remain in the percolating pores of the Co–Mo–S covalent network. XANES of Co K‐edge shows multiple electronic transitions, including quadrupole (1s→3d), shakedown (1s→4p + MLCT), and dipole allowed 1s→4p transitions. Remarkably, despite a lack of regular channels as in some crystalline solids, the amorphous KCMS gel shows ion‐exchange properties with UO₂²⁺ions. Additionally, it also presents surface sorption via [S∙∙∙∙UO₂²⁺] covalent interactions. Overall, this study underscores the synthesis of quaternary chalcogels incorporating alkali metals and their potential to advance separation science for cations and oxo‐cationic species by integrating a synergy of surface sorption and ion‐exchange.

Producing hydrochar from landfill municipal solid wastes (MSW) is a sustainable alternative to existing waste management practices in low‐ and middle‐income countries. In this study, mixed MSW feedstock (sent for landfilling) was subjected to hydrothermal carbonization to produce hydrochars. The hydrochar showing the highest heating value was subjected to pyrolysis at 5, 10, and 20 K min⁻¹heating rates. Based on the pyrolysis characteristics, a three pseudo‐component‐based distributed activation energy model was employed to describe the pyrolysis kinetics. The activation energy distributions for the three pseudo‐components were 140 ± 8.7 kJ mol⁻¹, 190 ± 1 kJ mol⁻¹and 175.9 ± 24.9 kJ mol⁻¹, which were able to predict the pyrolysis profile at all heating rates withR² > 0.999. Differential thermogravimetric profiles of the hydrochar revealed its pyrolytic reactivity to resemble lignocellulosic constituents. Fourier‐transform infrared analysis of the hydrochar showed retention of oxygen‐containing functional groups (associated with lignocellulosic constituents) from the parent feedstock. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.

Hyperpolarized orthohydrogen (o‐H₂) is a frequent product of parahydrogen‐based hyperpolarization approaches like signal amplification by reversible exchange (SABRE), where the hyperpolarizedo‐H₂signal is usually absorptive. We describe a novel manifestation of this effect wherein large antiphaseo‐H₂signals are observed, with¹H enhancements up to ≈500‐fold (effective polarizationP_H≈1.6 %). This anomalous effect is attained only when using an intact heterogeneous catalyst constructed using a metal–organic framework (MOF) and is qualitatively independent of substrate nature. This seemingly paradoxical observation is analogous to the “partial negative line” (PNL) effect recently explained in the context of Parahydrogen Induced Polarization (PHIP) by Ivanov and co‐workers. The two‐spin order of theo‐H₂resonance is manifested by a two‐fold higher Rabi frequency, and the lifetime of the antiphase HPo‐H₂resonance is extended by several‐fold.