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Zeolite imidazolate frameworks (ZIFs) have recently attracted eminent attention in the field of photocatalytic hydrogen generation. Herein, we first report and demonstrate the π–π interactions among bimetallic ZnCd-ZIF-8 and GO and their probed catalytic activity over the photocatalytic hydrogen generation efficiency. The successful synthesis of bimetallic ZIFs (ZnCd-ZIF-8) with the confined loading of a porous nanospace on GO enhances photocatalytic efficiency. The synthesized GO/ZnCd-ZIF-8(10) exhibited exceptional photocatalytic hydrogen generation efficiency of 2.4 mmol g–1 h–1 and AQY of 1.56% in 4 h. The optical and photoelectrochemical studies of the photocatalysts demonstrate the proximity of the catalytic active centers of GO toward water splitting and the Zn-Cd metal centers, with their chemical binding and stabilization, with increased electron–hole separation efficiency and charge transfer over the nanopores. The real-time studies demonstrate that the strong π–π interactions between ZnCd-ZIF-8 and GO are highly efficient toward photoinduced charge separation, confirmed through the Nyquist plot, which demonstrates their easy electron transfer over the hybrid photocatalyst, further leading to effectively enhanced water splitting. [ABSTRACT FROM AUTHOR]

With the most advances made so far in terms of photocatalyst design and preparation (inorganic photoredox nanoparticles), researchers of different expertise joined together to address sustainable energy conversion. Despite notable advancements in creating exceptionally active photocatalysts, the practical scalability of these innovations is hindered by issues such as ineffective utilization of solar energy and mass transport, recombination reactions, catalyst instability, and photo corrosion of the catalyst. In this roadmap review, we brief the fundamentals, latest progress, outstanding challenges, and novel design methodology for anticorrosive photocatalysts favorable to large‐scale hydrogen production. To enable the effective scaling of photocatalysis, beyond the inherent activity of photocatalysts, a range of additional factors are considered, with a primary focus on the design of photocatalytic systems. This review underlines the significance of well‐structured photocatalyst design and evaluation for achieving reproducibility and using dependable research methodology for conducting rigorous experiments. The recommendations are directed at reducing the uncertainty surrounding the optimism presented in published research, and we spotlight our recent research advancements. Importantly, the synergistic integration of design principles and research methodologies to enhance the anti‐corrosion properties of photocatalysts may pave the way for a practical technology to utilize solar energy for large‐scale hydrogen production efficiently. This article is categorized under:Sustainable Energy > Solar Energy [ABSTRACT FROM AUTHOR]

Developing acid-stable oxygen evolution/reduction reaction (OER/ORR) electrocatalysts is essential for high-performance water splitting. Still, the slow kinetics of the ORR and OER during the discharge and charge processes seriously impede their advancement in these performances. This report outlines the creation of a nitrogen-doped porous carbon matrix (NC) produced from a zeolitic imidazolate framework (ZIF-8). The matrix includes spatially engineered ultra-low loaded Ru atomic sites and is examined in the context of electrocatalytic oxygen evolution studies. The systematic analysis and computational studies reveal that the Ru atomic sites act as central driving forces, and their formation is confirmed through X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) analyses, specifically X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). These analyses emphasize the presence of Ru–O bonds at approximately 1.4 Å. Moreover, these results were validated by HRTEM, STEM, and HAADF investigations which emphasize the dispersion of atom-scale Ru on the NC(ZnO). Ru1.75@NC(ZnO) shows a low overpotential (320 mV) at a current density of 10 mA cm−2 for the OER because of the high active site utilization. Importantly, the Ru1.75@NC(ZnO) electrode displays an admirable specific capacitance value of 0.0501 mF cm−2 with notable durability of the capacitor after 500 cycles. The studies revealed that the introduction of monometallic Ru into ZIF-derived ZnO tunes intermediate adsorption energies and promotes the reactions by demanding lesser free energy in the water dissociation process. This research advances the pursuit of creating high-efficiency electrocatalysts with single-site structures, aiming for maximum atomic utilization efficiency in oxygen evolution reactions (OERs), particularly on templates derived from ZIFs. [ABSTRACT FROM AUTHOR]

We report here the design and synthesis of hybrid ternary heterostructure, Cu-(OH)2/P-(g-C3N4)/MoS2, toward efficient visible-light driven hydrogen production through water reduction. The proposed hierarchical composite comprising of MoS2 and Cu-(OH)2 as a cocatalyst is stabilized onto P-(g-C3N4). The robust hybrid photocatalyst demonstrates remarkable HER activity, superior light harvesting and charge transfer kinetics, resulting in a high hydrogen production rate of 12.01 mmol h–1 g–1 and AQY of 19.8%, where the efficiency is enhanced by approximately 40 times compared to the pristine P-(g-C3N4). Our advanced heterostructure composite design strategies supported by X-ray, XPS, EPR, PL-TCSPC, and electron microscopy with DFT calculations enabled us to correlate the electronic structure with charge transfer kinetics for higher activities and thereby satisfy all the stringent requirements for practical solar-driven hydrogen evolution applications. [ABSTRACT FROM AUTHOR]

The presence of transition-metal single-atom catalysts effectively enhances the interaction between the substrate and reactant molecules, thus exhibiting extraordinary catalytic performance. In this work, we for the first time report a facile synthetic procedure for placing highly dispersed Ru single atoms on stable CNF(ZnO) nanocages. We unravel the atomistic nature of the Ru single atoms in CNF(ZnO)/Ru systems using advanced HAADF-STEM, HRTEM, and XANES analytical methods. Density functional theory calculations further support the presence of ruthenium single-atom sites in the CNF(ZnO)/Ru system. Our work further demonstrates the excellent photocatalytic ability of the CNF(ZnO)/Ru system with respect to H 2 production (5.8 mmol g -1 h -1 ) and reduction of CO 2 to CH 3 OH [249 μmol (g of catalyst) -1 ] with apparent quantum efficiencies of 3.8% and 1.4% for H 2 and CH 3 OH generation, respectively. Our studies unambiguously demonstrate the presence of atomically dispersed ruthenium sites in CNF(ZnO)/Ru catalysts, which greatly enhance charge transfer, thus facilitating the aforementioned photocatalytic redox reactions.

The S-scheme heterojunction photocatalyst holds potential for better photocatalysis owing to its capacity to broaden the light absorption range, ease electron-hole separation, extend the charge carrier lifespan, and maximize the redox ability. In this study, we integrate zeolitic imidazolate frameworks (ZIFs-67) with the CuFe-LDH composite, offering a straightforward approach towards creating a novel hybrid nanostructure, enabling remarkable performance in both photocatalytic hydrogen (H 2 ) evolution and carbon dioxide (CO 2 ) to methanol (MeOH) conversion. The ZIF-67/CuFe-LDH photocatalyst exhibits an enhanced photocatalytic hydrogen evolution rate of 7.4 mmol g -1 h -1 and an AQY of 4.8%. The superior activity of CO 2 reduction to MeOH generation was 227 μmol g -1 h -1 and an AQY of 5.1%, and it still exhibited superior activity after continuously working for 4 runs with nearly negligible decay in activity. The combined spectroscopic analysis, electrochemical study, and computational data strongly demonstrate that this hybrid material integrates the advantageous properties of the individual ZIF-67 and CuFe-LDH exhibiting distinguished photon harvesting, suppression of the photoinduced electron-hole recombination kinetics, extended lifetime, and efficient charge transfer, subsequently boosting higher photocatalytic activities.