Development of Sustainable Catalyst Coating of Ni₂P Engineered SrTiO₃ Nanocubes for Hydrogen Generation

Abstract

Ni 2 P has a significant importance in the field of photocatalytic water splitting, irrespective of its narrow band gap (1.0 eV). The photocatalytic performance of bare Ni 2 P is highly limited due to the fast recombination rate of the electron−hole pairs. However, it can be used suitably for tuning the band gap of wide band gap semiconductors. The present study involves the development of an effective heterojunction with tuned band gap by Ni 2 P engineered SrTiO 3 nanocubes in the form of a coating after successful compositional tuning. This is accomplished by an in situ decoration of SrTiO 3 nanocubes at the active sites of Ni 2 P via a chemical reduction method. Morphological and physical features of the developed catalyst are tuned in the coating in order to have Ni 2 P as the major phase for maintaining the physical structure and to impart enhancement in photocatalytic performance and stability to the catalyst system. As the conduction band of SrTiO 3 lies at a more negative potential compared to that of Ni 2 P, the excited electrons from SrTiO 3 can easily be injected to the active sites of Ni 2 P for proton reduction. Thus, in addition to tuning the composite energy band gap, Ni 2 P acts as the reaction center for hydrogen generation and as the stable catalyst bed for SrTiO 3 nanocube decoration. The appearance of SrTiO 3 enriches the electron density at the Ni 2 P active sites, and Ni 2 P with negatively charged phosphorus has the ability to capture more protons at these sites for accelerating the rate of hydrogen generation. The enhancement in the microsurface properties of Ni 2 P in the composite coating are evaluated with OSP technique. The hydrogen generation rate as high as 7.03 mmol/g/h is achieved with the as-engineered catalyst coating, with an apparent quantum yield of 23.72% at 400 nm. The catalyst system shows a sustained hydrogen generation rate even after 15 cycles confirming the suitability of large scale production for industrial applications.

Yeast Reduced Ti3+ Self-Doped SrTiO3/rGO-In-Ni2P Nanocomposite for Efficient Visible Light-Driven Hydrogen Generation

“…The composite incorporated coating exhibited a notably higher current density compared to bare Ni 2 P, suggesting a substantial reduction in the energy consumption linked with the electrochemical process . Further, the competency in the hydrogen production efficiency of the optimized 5_SrTiO 3 /yrGO-Ni 2 P photocatalytic coating is analyzed with recently published similar photocatalysts and the data are summarized in Table . − The results show the industrial importance of the photocatalytic coating developed in the present work for the large-scale generation of hydrogen with a prolonged cycle life.…”

Tuning and Sustainment of High Surface Area of Nano CeO2-Anchored NiMOF Flake Heterojunctions for Efficient Photocatalytic Hydrogen Generation

“…CeO 2 and NiMOF are oppositely charged, which means that the positively charged CeO 2 particles can be strongly deposited over negatively charged NiMOF via electrostatic attraction . Also, the higher magnitude of zeta potential in 0.2:1-CeO 2 @NiMOF compared to the pure components reveals that the particles tend to repel each other in the composite which imparts improved stability and better dispersibility as seen from the FESEM micrographs . The surface modification strategy adopted as per this study has a major intention that the SSA of pure NiMOF should be increased for enhanced flexibility in catalytic applications.…”

“…42 Also, the higher magnitude of zeta potential in 0.2:1-CeO 2 @ NiMOF compared to the pure components reveals that the particles tend to repel each other in the composite which imparts improved stability and better dispersibility as seen from the FESEM micrographs. 43 The surface modification strategy adopted as per this study has a major intention that the SSA of pure NiMOF should be increased for enhanced flexibility in catalytic applications. As one of the major drawbacks of pure NiMOF is its poor surface area as reported, the extent of improvement in the SSA of smooth NiMOF flakes with CeO 2 anchoring is studied with BET studies as depicted in the next section.…”

Development of an intense yellow-coloured BiVO4/ZrO2composite coating for anticorrosion multifunctional cool roofing

“…Initially, a mild steel substrate was subjected to hot-dip galvanization after different pre-treatment processes and fixing of the galvanization process's operating parameters. [25][26][27] After various processes, such as cleaning with acetone followed by drying, the traditional hot-dip galvanization was modified by a process of phosphating, which included immersion of the coatings in a phosphating bath for 20 min in the presence of BVZ composite. The bath compositions are summarized in Table S1 (ESI †).…”