Photocatalytic conversion of carbon dioxide (CO(2)) to hydrocarbons such as methanol makes possible simultaneous solar energy harvesting and CO(2) reduction, two birds with one stone for the energy and environmental issues. This work describes a high photocatalytic conversion of CO(2) to methanol using graphene oxides (GOs) as a promising photocatalyst. The modified Hummer's method has been applied to synthesize the GO based photocatalyst for the enhanced catalytic activity. The photocatalytic CO(2) to methanol conversion rate on modified graphene oxide (GO-3) is 0.172 μmol g cat(-1) h(-1) under visible light, which is six-fold higher than the pure TiO(2).

Flexible supercapacitors, a state-of-the-art material, have emerged with the potential to enable major advances in for cutting-edge electronic applications. Flexible supercapacitors are governed by the fundamentals standard for the conventional capacitors but provide high flexibility, high charge storage and low resistance of electro active materials to achieve high capacitance performance. Conducting polymers (CPs) are among the most potential pseudocapacitor materials for the foundation of flexible supercapacitors, motivating the existing energy storage devices toward the future advanced flexible electronic applications due to their high redox active-specific capacitance and inherent elastic polymeric nature. This review focuses on different types of CPs-based supercapacitor, the relevant fabrication methods and designing concepts. It describes recent developments and remaining challenges in this field, and its impact on the future direction of flexible supercapacitor materials and relevant device fabrications.

The production of renewable solar fuel through CO2 photoreduction, namely artificial photosynthesis, has gained tremendous attention in recent times due to the limited availability of fossil-fuel resources and global climate change caused by rising anthropogenic CO2 in the atmosphere. In this study, graphene oxide (GO) decorated with copper nanoparticles (Cu-NPs), hereafter referred to as Cu/GO, has been used to enhance photocatalytic CO2 reduction under visible-light. A rapid one-pot microwave process was used to prepare the Cu/GO hybrids with various Cu contents. The attributes of metallic copper nanoparticles (∼4-5 nm in size) in the GO hybrid are shown to significantly enhance the photocatalytic activity of GO, primarily through the suppression of electron-hole pair recombination, further reduction of GO's bandgap, and modification of its work function. X-ray photoemission spectroscopy studies indicate a charge transfer from GO to Cu. A strong interaction is observed between the metal content of the Cu/GO hybrids and the rates of formation and selectivity of the products. A factor of greater than 60 times enhancement in CO2 to fuel catalytic efficiency has been demonstrated using Cu/GO-2 (10 wt % Cu) compared with that using pristine GO.

Photocatalytic formation of hydrocarbons using solar energy via artificial photosynthesis is a highly desirable renewable-energy source for replacing conventional fossil fuels. Using an l-cysteine-based hydrothermal process, here we synthesize a carbon-doped SnS2 (SnS2-C) metal dichalcogenide nanostructure, which exhibits a highly active and selective photocatalytic conversion of CO2 to hydrocarbons under visible-light. The interstitial carbon doping induced microstrain in the SnS2 lattice, resulting in different photophysical properties as compared with undoped SnS2. This SnS2-C photocatalyst significantly enhances the CO2 reduction activity under visible light, attaining a photochemical quantum efficiency of above 0.7%. The SnS2-C photocatalyst represents an important contribution towards high quantum efficiency artificial photosynthesis based on gas phase photocatalytic CO2 reduction under visible light, where the in situ carbon-doped SnS2 nanostructure improves the stability and the light harvesting and charge separation efficiency, and significantly enhances the photocatalytic activity.

Selective formation of 2,5-dimethylfuran (DMF) by hydrogenolysis of lignocellulosic biomass-derived 5-hydroxymethylfurfural (HMF) is highly desirable for renewable liquid biofuel production. Here we have synthesized Cu–Pd bimetallic nanoparticles embedded in carbon matrix (Cu–Pd@C) by simple pyrolysis of Pd-impregnated Cu-based metal–organic frameworks (MOFs) followed by conventional hydrogenation route. It was found that Cu–Pd@C-B (solid–gas-phase hydrogenation route) with Cu–Pd bimetallic alloying exhibited brilliant catalytic performance at 120 °C under 15 bar H2 pressure to produce liquid DMF biofuel with 96.5% yield from HMF as compared with the Cu–Pd@C-A catalyst (liquid phase hydrogenation route), which gave 46.4% yield under the same conditions. X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge structure (XANES) studies reveal that Pd in Cu–Pd@C-B catalyst is electronically promoted by Cu with the unique intrinsic synergy of increased Pd–Pd bond distance and decreased Cu–Cu bond length, which eventually modulate the local atomic structural environment and result in enhanced catalytic activity. Moreover, the entrapped bimetallic nanoparticles with carbon shells in Cu–Pd@C-B catalyst further protect the active catalytic site from migration, aggregation, and leaching during hydrogenolysis reaction and improve the stability of the catalyst.

One of the key challenges in artificial photosynthesis is to design a photocatalyst that can bind and activate the CO molecule with the smallest possible activation energy and produce selective hydrocarbon products. In this contribution, a combined experimental and computational study on Ni-nanocluster loaded black TiO (Ni/TiO ) with built-in dual active sites for selective photocatalytic CO conversion is reported. The findings reveal that the synergistic effects of deliberately induced Ni nanoclusters and oxygen vacancies provide (1) energetically stable CO binding sites with the lowest activation energy (0.08 eV), (2) highly reactive sites, (3) a fast electron transfer pathway, and (4) enhanced light harvesting by lowering the bandgap. The Ni/TiO photocatalyst has demonstrated highly selective and enhanced photocatalytic activity of more than 18 times higher solar fuel production than the commercial TiO (P-25). An insight into the mechanisms of interfacial charge transfer and product formation is explored.

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Porous-Organic-Polymers (POPs) constructed through covalent bonds have raised tremendous research interest because of their suitability to develop robust catalysts and their successful production with improved efficiency. In this work, we have designed and explored the properties and catalytic activity of template-free construction hydroxy (-OH) group enriched porous-organic-polymer (Ph-POP) bearing functional Pd nanoparticles (Pd-NPs) by one-pot condensation of phloroglucinol (1,3,5-trihydroxybenzene) and terephthalaldehyde followed by solid phase reduction with H 2 . The encapsulated Pd-NPs rested within welldefined POP nanocages and remained undisturbed from aggregation and leaching. This polymer hybrid nanocage Pd@Ph-POP is found to enable efficient liquid-phase hydrodeoxygenation (HDO) of acetophenone (AP) with high selectivity (99%) of ethylbenzene (EB) and better activity than its Pd@Al 2 O 3 counter-part. Our investigation demonstrates a facile, scalable, catalyst-template free methodology for developing novel porous-organic-polymer catalysts and next generation efficient greener chemical processes from platform molecules to value-added chemicals. With the aid of comprehensive in situ ATR-IR spectroscopic experiments, it is suggested that EB can be more easily desorbed in solution, reflecting from the much weaker but resolved signals at 1494 cm -1