An electrocatalytic nitrogen reduction reaction is considered a potential approach for green ammonia productiona zero-carbon fertilizer, fuel, and energy storage for renewable energy. To harness the synergistic properties of perovskites, the inherent dipole moment due to their non-centrosymmetric structure (that facilitates better charge separation), oxygen vacancies, and the presence of Ni metal sites that permit activation and reduction of N2 efficiently, the NiTiO3-based nanoelectrocatalysts have been synthesized. Further, these catalysts have been modified with ultra-small metal nanocrystal co-catalysts to form heterointerfaces that not only aid to improve the charge separation but also activate N2 and lower overpotential requirements. The appearance of peaks corresponding to (012), (104), (110), (11–3), (024), (11–6), (018), (027), and (300) confirms the formation of rhombohedral NiTiO3. The shift in the XRD peak corresponding to the (104) plane to a smaller 2θ value and peak shifting and widening of Raman spectra imply the lattice distortion that signifies the formation of Pd–NiTiO3 and Pt–NiTiO3 heterojunction electrocatalysts with the loadings of 0.4 and 0.3 wt % of Pd and Pt, respectively, as confirmed by ICP-OES analysis. The detailed XPS analysis reveals the presence of Pd (0), Pd (II), and Pt (0), Pt (II) in respective electrocatalysts. The appearance of XPS peaks at 528.7 and 531.1 eV suggests the presence of oxidative oxygen species (O2–/O–) and the presence of oxygen defects due to oxygen vacancy. The detailed nitrogen reduction (NRR) investigation exhibits a 5-fold enhancement in ammonia yield rate (∼14.28 μg h–1 mg–1 at −0.003 V vs RHE), a faradic efficiency of 27% (at 0.097 V vs RHE) for Pd–NiTiO3 electrocatalysts than that for bare NiTiO3 (3.08 μg h–1 mg–1), and 9-folds higher than that of the activity shown by the commercial TiO2 (P25) (1.52 μg h–1mg–1). The formation of ammonia was further confirmed by using isotopic nitrogen as the feeding gas. Furthermore, the highest NRR is observed at lower cathodic potential (−0.003 V vs RHE) in the case of the Pd–NiTiO3 electrocatalyst than that of the Pt–NiTiO3 electrocatalyst (−0.203 V vs RHE), implying significantly reduced overpotential requirement. Such enhanced NRR activity with lower overpotential requirement in the case of the Pd–NiTiO3 electrocatalyst is due to efficient charge separation as shown by the semicircle Nyquist plot, decreased photoluminescence emission intensity, shorter average lifetime (∼29 ns) of excitons, appropriate band bending, and improved activation of N2 by the oxygen vacancies and heterointerface formed between Pd nanocrystals and NiTiO3. Furthermore, no change is observed in the current density, after stabilization in the initial few seconds, even up to 2 h, which signifies that these electrocatalysts are stable. The structural and morphological integrity of the optimized catalyst remained even after the nitrogen reduction reactions, as revealed by no significant change observed in FESEM, elemental mapping, and EDS ana...

The growing contamination of endocrine-disrupting compounds (EDCs) in water is posing a serious threat to the reproductive, neuro, and other endocrine intercedes functions in humans and animals. One of the...

The design of heterostructured photocatalysts comprising of 2-D mesoporous C 3 N 3 (π-conjugated bonds with one less nitrogen atom in the ring to promote the better electron transport unlike conventional g-C 3 N 4 ) donor coupled with the MoS 2 acceptor by a template-directed thermal synthesis followed by hydrothermal synthesis is presented. The formation and coupling of MoS 2 through basal planes on the surface of mpg-CN has been confirmed by the XRD, XPS (C/N ratio of the order of 1), and lengthening of the CÀ N bond as revealed by increasing intensity of FTIR peak (1232 cm À 1 ), respectively. Upon optimization, MS-mpg-CN exhibits 10-fold enhancement in hydrogen generation rate and efficiency (~86500 μmolg À 1 h À 1 , IPCE: ~64 %) than that of observed for MS-mpg-C 3 N 4 photocatalyst (~8250 μmolg À 1 h À 1 , IPCE: ~5.6 %). The lower PL emission intensity, average lifetime (1.91 ns) of charge carriers, precise semicircle in Nyquist plot and higher degree of band bending (E fb À 0.64 eV), higher 'g' value (2.0038) in the EPR imply improved charge carrier separation, transfer kinetics and formation of intimate heterojunction, respectively. Furthermore, hydrogen evolution measured for subsequent days while reusing photocatalyst shows no significant change in the activity (~1.2 % variation over three consecutive cycles), confirming their photostability and reusability.