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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]

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 discriminate etching chemistry (crystal engineering) of metal–organic frameworks (MOFs) offers promising opportunities for tailoring electron–hole separation, and charge-carrier utilization plays a central role in photocatalysis. Herein, the noble metal-free examples of polyaniline (PANI)-sensitized cobalt oxide functionalized perfect crystal UiO-66 and defective crystal UiO-66D photocatalysts were synthesized and evaluated for photocatalytic hydrogen generation from water under visible light irradiation. A viable route for the simple yet effective modification of UiO-66 by implanting PANI and cobalt oxide was demonstrated for the development of a series of UiO-66-based catalysts. The UiO-66-PANI-Co3O4 catalyst showed staggeringly enhanced photocatalytic activity, which was 24 times that of the pristine UiO-66(Zr). [ABSTRACT FROM AUTHOR]

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.

Solid adsorbents with precise surface structural chemistry and porosity are of immense interest to decode the structure-property relationships and maintain an energy-intensive path while achieving high activity and durability. In this work, we reported a series of amine-modified zeolites and their CO 2 capture efficiencies. The amine impregnated molecular zeolite compounds were characterized and systematically investigated for CO 2 adsorption capacity through thermogravimetric analysis for the occurrence of atmospheric pure CO 2 gas at 75 °C with diethylenetriamine (DETA), ethylenediamine (EDA), monoethanolamine (MEA), and triethanolamine (TEA)-loaded zeolite 13X, 4A, and 5A adsorbents. The kinetics of the adsorption study indicated that the adsorption capacity for CO 2 adsorption was improved with amine loading up to a certain concentration over 13X-DETA-40, showing an adsorption capacity of 1.054 mmol of CO 2 per gram of zeolite in a very short amount of time. The result was especially promising in terms of the initial adsorption capacity of zeolite, which adsorbed approximately 0.8 mmol/g zeolite within the first two minutes of experimentation. A detailed flow chart that includes a brief look into the process adopted for adsorption was included. Lagergren pseudo-first- and pseudo-second-order models of 40 wt % DETA zeolite 13X gave CO 2 adsorption capacities of 1.055 and 1.058 mmol/g and also activation energies of 86 and 76 kJ/mol, respectively. The CO 2 adsorption capacity of 13X-DETA-40 in a lab-scale reactor was found to be 1.69 mmol/g. A technoeconomic study was conducted for the solid amine zeolites to understand the investment per ton of CO 2 adsorbed. This study was used as a basis to improve cost estimates from a microscale to a lab-scale reactor. The cost of investment for 13X-DETA-40 was reduced by 84% from $49,830/ton CO 2 adsorbed in a microscale reactor to $7,690/ton of CO 2 adsorbed in a lab-scale reactor., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

The discriminate etching chemistry (crystal engineering) of metal-organic frameworks (MOFs) offers promising opportunities for tailoring electron-hole separation, and charge-carrier utilization plays a central role in photocatalysis. Herein, the noble metal-free examples of polyaniline (PANI)-sensitized cobalt oxide functionalized perfect crystal UiO-66 and defective crystal UiO-66D photocatalysts were synthesized and evaluated for photocatalytic hydrogen generation from water under visible light irradiation. A viable route for the simple yet effective modification of UiO-66 by implanting PANI and cobalt oxide was demonstrated for the development of a series of UiO-66-based catalysts. The UiO-66-PANI-Co3O4 catalyst showed staggeringly enhanced photocatalytic activity, which was 24 times that of the pristine UiO-66(Zr).