Ammonia is the main precursor for the production of fertilizers, a hydrogen energy carrier and an emerging clean fuel that plays a crucial role in sustaining life on the globe.

We reported the fabrication of an electrochemical sensor for uric acid (UA) monitoring using metal-free electrode based on heteroatoms (S, N, P, and O) doped carbon (HADC) nanoparticles, derived from polyphosphazene, synthesized via precipitation polymerization reaction between hexachlorocyclotriphosphazene (HCCP) and 1,4-dithiane-2,5-diol (DD) under sonication irradiations at 40 °C, following its modification with benzimidazolium-1-acetate ionic liquid (BIL). The developed HADC-BIL electrode showed a highly sensitive and selective response toward UA even in the presence of highly electroactive interferences such as ascorbic acid (AA), dopamine (DA), glucose (Glu), and hydrogen peroxide (H2O2). Our results demonstrated that the as-fabricated HADC-BIL electrode allows us to detect UA over a linear range of 2–1050 μM with a detection limit of 1.27 μM. Further, we were able to monitor the amount of UA level in the blood of a gout patient using the developed HADC-BIL electrode, which ensures the effectiveness of the developed sensor for the sensitive and selective detection of UA from real samples.

Light-powered fuel-free colloidal motors possess significant potential for practical applications ranging from nanomedicine to environmental remediation. However, current lightpowered colloidal motors often require the incorporation of expensive metals or high concentrations of toxic chemical fuels, which is a severe limitation for their practical applications. Integrating highly ordered and porous materials with a large surface area into colloidal motors is a promising strategy for upsurging their self-propelled speed and adsorption, which will benefit many applications. Here, highly efficient, fuel-free, and light-activated metal organic framework (MOF)-3trimethoxysilyl propyl methacrylate Janus colloidal motors with a hierarchical morphology are reported. These colloidal motors can be driven by UV or visible light, with a self-propelled speed tuned by the light intensity. The speed can be further enhanced by morphology optimization or by the addition of H 2 O 2 as a fuel. The colloidal motors display a superior efficiency in removing heavy metal ions of Hg, which is up to ∼90% within 40 min from the contaminated water, attributed to their high surface area, hierarchical morphology, large number of active sites, and high mobility. This work not only offers a facile approach to incorporate a versatile MOF family into the design of fuel-free and light-powered Janus colloidal motors, but also demonstrates their potential for real-life applications such as environmental remediation.

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The synergy between nitrogen (N) and sulfur (S) in quaternary heteroatom-doped carbons is rarely probed, although these elements can significantly alter the performance of the oxygen evolution reaction (OER). Herein, quaternary heteroatom (N, S, P, O)-doped multishelled carbon (NSPO-C) nanospheres are synthesized from heteroatom-containing poly­(cyclotriphosphazene-codioxo-thiane) (PCD) polymer nanospheres. The contents of these quaternary heteroatoms were controlled via a facile carbonization process. The OER performance was tested, which was found to be related to the N and S contents, and the as-prepared NSPO-C-8 nanosphere anode with optimized contents of N (2.76 wt %) and S (1.52 wt %) showed a maximum OER activity, that is, it required a very low overpotential of 339 mV to obtain a current density of 10 mA cm–2 with a low Tafel slope value (39.40 mV dec–1), which is much lower than its conventional RuO2 (401 mV), 20% Pt/C (566 mV), and PO-C nanosphere (452 mV) counterparts. Higher performance is attributed to the synergy between N and S in the NSPO-C nanospheres, which provides maximum exposure to electroactive sites, while special morphology ensures efficient pathways for fast charge transportation. These findings advocate that polyphosphazene-derived heteroatom-doped carbons are potential candidates to fabricate high-performance devices for water oxidation.