No abstract

No abstract

No abstract

In the present work, change in electronic properties due to structural modification of bilayer g-C3N4 using density functional theory has been studied. We have considered shifting and rotation of one layer parallel to the second fixed layer and optimised three different arrangements. The stability of the bilayer was examined by calculating the total energy of all the structures. Specific bilayer arrangement having 180° rotation has been found most stable. The study of density of states reveals band gap of this structure to be 0.60 eV. From HOMO-LUMO and partial density of states it is seen that the stability and properties of bilayer g-C3N4 highly depends on the arrangement of N-2p and C-2p orbitals in both the layers. The inclusion of van der Waals (vdW) interaction changes the properties in z axis due to coupled orbital and columbic interaction between the layers and individual orbitals.

Amorphous materials are used in multitude of catalytic applications, including electrocatalytic water-splitting. Identification and investigation of active sites in amorphous catalysts are rarely reported, mainly owing to the complexity of the systems. Herein, we report an amorphous bifunctional Co–W–B electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The optimized Co–W–B catalyst showed promising overpotential values of 97 mV (HER) and 292 mV (OER), respectively, to achieve 10 mA cm–2 in 1 M KOH, with good stability. The promoting effect of W in Co–B was investigated experimentally, while computational tools were used to identify all the possible catalytic sites in an amorphous Co–W–B model and classify the most preferred sites for HER and OER. The presence of multi-catalytic sites with specific selectivity toward HER and OER was observed, which explained the bifunctional activity of Co–W–B. This study will foster better understanding of the origin of catalytic activity in similar amorphous systems.