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Atomic‐level tailoring of active sites is an efficient strategy for designing high‐performance photocatalysts for clean energy. Asymmetric atomic sites (AAS) like MSA‐Ov‐M2 created through hetero‐metal single atoms (MSA) doping on defect‐rich metal oxides (M2‐Ov‐M2) are favored for better activation of targeted molecules. However, creating AAS typically demands high energy input, hindering their widespread use in photocatalytic H2 production. Furthermore, precise control over surface defects to create AAS remains challenging. Here, CuSA‐Ov‐Ti3c highly asymmetric atomic sites catalyst (HAASC) is constructed by strategically trapping Cu single atoms on high‐index (111) faceted TiO2. This material combines single‐atom catalysis and facet engineering, achieving unprecedented H2 production rates (8.3 mmol h−1 g−1 in pure water and 784.5 mmol h−1 g−1 in water/methanol mixture). Experimental and theoretical analyses reveal CuSA substituting five‐coordinated Ti atoms (Ti5c) next to three‐coordinated (Ti3c) ones, forming CuSA‐Ov‐Ti3c HAAS. HAAS plays multiple roles in i) improving light harvesting, charge‐transfer dynamics, and redox capability of photoexcited electrons; ii) enhanced adsorption and polarization of H2O molecules; iii) facilitating electron transfer from CuSA‐Ov‐Ti3c to H2O molecules, and iv) raising d‐band center toward Fermi level resulting in ≈250‐fold enhanced H2 production than Ti5c‐O‐Ti3c AASC. This work opens new avenues for future structural designs in heterogeneous catalysis for energy‐related applications. [ABSTRACT FROM AUTHOR]

Ionic tactile sensors (ITS) represent a new class of deformable sensory platforms that mimic not only the tactile functions and topological structures but also the mechanotransduction mechanism across the biological ion channels in human skin, which can demonstrate a more advanced biological interface for targeting emerging human‐interactive technologies compared to conventional e‐skin devices. Recently, flexible and even stretchable ITS have been developed using novel structural designs and strategies in materials and devices. These skin‐like tactile sensors can effectively sense pressure, strain, shear, torsion, and other external stimuli with high sensitivity, high reliability, and rapid response beyond those of human perception. In this review, the recent developments of the ITS based on the novel concepts, structural designs, and strategies in materials innovation are entirely highlighted. In particular, biomimetic approaches have led to the development of the ITS that extend beyond the tactile sensory capabilities of human skin such as sensitivity, pressure detection range, and multimodality. Furthermore, the recent progress in self‐powered and self‐healable ITS, which should be strongly required to allow human‐interactive artificial sensory platforms is reviewed. The applications of ITS in human‐interactive technologies including artificial skin, wearable medical devices, and user‐interactive interfaces are highlighted. Last, perspectives on the current challenges and the future directions of this field are presented. [ABSTRACT FROM AUTHOR]

A key challenge remains the preparation of an active and robust water oxidation photocatalyst with abundant earth materials. As a useful to improve photocatalytic efficiency, the development of α‐Fe2O3 nanocrystals with different exposed facets and interfaces has attracted enormous attention. But literature survey shows that α‐Fe2O3 nanomaterials were mainly used in photoelectrochemical cell for water splitting as anode materials. In this work, highly efficient Pt/PtOx cocatalyst decorated α‐Fe2O3 shaped‐photocatalysts were derived as photocatalyst for white light‐induced O2 generation from water without any electric potential. The maximum apparent quantum efficiency of photooxidation reaction was reached 55.33 % by Pt/PtOx decorated bitruncated‐dodecahedron shaped α‐Fe2O3 and around 30.5, 2.3, 1.28 times better than the Pt/PtOx decorated nanocuboid, nanorod and bitruncated‐octahedron shape respectively. The Pt/PtOx decorated bitruncated‐dodecahedron shaped α‐Fe2O3 display an unusual photooxidation activity with a high TOF (1.96×10−2 s−1) due to presence of destabilized and unsaturated Fe centre containing high energy {104} and {100} facets. The present findings clearly demonstrate that the selective O2 evolution from water can possible without any sacrificial agent. [ABSTRACT FROM AUTHOR]

Highlights • Gold nanoparticles deposited on mesoporous titania with isolated Si sites was synthesized. • Au/Ti 0.72 Si 0.28 O 2 catalyst exhibited superior activity for photocatalytic reduction of CO 2 into CH 3 OH. • The effects of Si sites on enhancing photocatalytic activity of TiO 2 were shown. Abstract Solar-driven chemical production of methanol from CO 2 has become a hot topic of research due to high-value addition, with methanol as a product, as well as reduction of CO 2 which is a greenhouse gas. Here we report gold nanoparticles deposited on mesoporous titania with isolated Si sites, which converted CO 2 into methanol under visible light irradiation using LED light source. Si amount in titania lattice was optimized to obtain the best methanol yield. DFT calculation showed that Si sites incorporation was responsible for higher adsorption of CO 2 onto the surface, which was further proved experimentally with CO 2 uptake results. We achieved highest methanol production of 1835 μmolg cat −1 using Au/Ti x Si 1− x O 2 material with 28 mol% Si in titania lattice and 1.0 wt% Au nanoparticles deposition. The Au/Ti x Si 1− x O 2 photocatalysts were thoroughly characterized by inductively coupled plasma atomic emission (ICP-AES) spectrometry, powder X-ray diffraction (PXRD), field emission scanning electron microscopy (FE-SEM), high angle annular dark field-scanning transmission electron microscopic (HAADF-STEM), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDX), 29Si MAS NMR, UV-vis diffuse reflection spectroscopy (DRS), N 2 sorption studies, CO 2 uptake experiments, cyclic voltammetry (CV) and DFT calculations. The products were analyzed by GC-FID, GC–MS, and HPLC. The photocatalytic reaction was monitored using in situ FT-IR which established the formation of formaldehyde as an intermediate product which further converted into methanol. [ABSTRACT FROM AUTHOR]

A novel MnFe2O4-porous organic polymer (POP) nanocomposite was synthesized by a facile hydrothermal method and using the highly cross-linked N-rich benzene-benzylamine POP. The nanocomposite presented highly efficient photocatalytic performance in the hydrogen evolution reaction (HER) from pure water without addition of any sacrificial agent under one AM 1.5 G sunlight illumination. A photocatalytic activity of 6.12 mmol h−1 g−1 was achieved in the absence of any noble metal cocatalyst, which is the highest H2 production rate reported for nonprecious metal catalysts. The photocatalytic performance of MnFe2O4-POP could be attributed to the intrinsic synergistic effects of manganese ferrite (MnFe2O4) nanoclusters interacting with the nitrogen dopant POP with a unique mesoporous nanoarchitecture and spatially confined growth of MnFe2O4 in the interconnected POP network, leading to high visible-light absorption with fast electron transport. [ABSTRACT FROM AUTHOR]

A large number of scientific investigations are needed for developing a sustainable solid sorbent material for precombustion CO 2 capture in the integrated gasification combined cycle (IGCC) that is accountable for the industrial coproduction of hydrogen and electricity. Keeping in mind the industrially relevant conditions (high pressure, high temperature, and humidity) as well as good CO 2 /H 2 selectivity, we explored a series of sorbent materials. An all-rounder player in this game is the porous organic polymers (POPs) that are thermally and chemically stable, easily scalable, and precisely tunable. In the present investigation, we successfully synthesized two nitrogen-rich POPs by extended Schiff-base condensation reactions. Among these two porous polymers, TBAL-POP-2 exhibits high CO 2 uptake capacity at 30 bar pressure (57.2, 18.7, and 15.9 mmol g -1 at 273, 298, and 313 K temperatures, respectively). CO 2 /H 2 selectivities of TBAL-POP-1 and 2 at 25 °C are 434.35 and 477.93, respectively. On the other hand, at 313 K the CO 2 /H 2 selectivities of TBAL-POP-1 and 2 are 296.92 and 421.58, respectively. Another important feature to win the race in the search of good sorbents is CO 2 capture capacity at room temperature, which is very high for TBAL-POP-2 (15.61 mmol g -1 at 298 K for 30 to 1 bar pressure swing). High BET surface area and good mesopore volume along with a large nitrogen content in the framework make TBAL-POP-2 an excellent sorbent material for precombustion CO 2 capture and H 2 purification.

A novel MnFe 2 O 4 -porous organic polymer (POP) nanocomposite was synthesized by a facile hydrothermal method and using the highly cross-linked N-rich benzene-benzylamine POP. The nanocomposite presented highly efficient photocatalytic performance in the hydrogen evolution reaction (HER) from pure water without addition of any sacrificial agent under one AM 1.5 G sunlight illumination. A photocatalytic activity of 6.12 mmol h -1  g -1 was achieved in the absence of any noble metal cocatalyst, which is the highest H 2 production rate reported for nonprecious metal catalysts. The photocatalytic performance of MnFe 2 O 4 -POP could be attributed to the intrinsic synergistic effects of manganese ferrite (MnFe 2 O 4 ) nanoclusters interacting with the nitrogen dopant POP with a unique mesoporous nanoarchitecture and spatially confined growth of MnFe 2 O 4 in the interconnected POP network, leading to high visible-light absorption with fast electron transport., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We report a non-trivial facile chemical approach using ionic liquid ([bmim][Cl]) as a porogen for the synthesis of (001) faceted TiO2 nanocrystals having mesoscopic void space. This faceted TiO2 nanomaterial has been doped with Pt nanoclusters through chemical impregnation. The resulting Pt-doped TiO2 nanomaterials are thoroughly characterized by powder X-ray diffraction (PXRD), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), ultra high resolution transmission electron microscopy (UHR-TEM), energy dispersive X-ray spectrometry (EDX), UV-vis diffuse reflection spectroscopy (DRS) and N2 sorption studies. These Pt/TiO2 nanocrystals with (001) exposed facets are employed as efficient and benign catalysts for hydrogen production from pure water and methanol-water systems under one AM 1.5G sunlight illumination. The effect of platinum loading and methanol-water ratio on the photocatalytic activity of the faceted TiO2 nanocrystals are investigated and it is found that hydrogen evolution rates have been enhanced significantly upon Pt loading. Under optimized reaction conditions the highest photocatalytic activity of 11.2 mmol h(-1) g(-1) has been achieved over ca. 1.0 wt% Pt loaded Pt/TiO2 nanocrystals with (001) exposed facets, which is one of the highest hydrogen evolution rates over the noble metal/TiO2 system reported to date in the literature.

Development of unique nanoheterostructures consisting of indium oxide nanoclusters like species doped on the TiO2 nanocrystals surfaces with {101} and {001} exposed facets, resulted in unprecedented sacrificial hydrogen production (5.3 mmol h(-1) g(-1)) from water using methanol as a sacrificial agent, under visible light LED source and AM 1.5G solar simulator (10.3 mmol h(-1) g(-1)), which is the highest H2 production rate ever reported for titania based photocatalysts, without using any noble metal cocatalyst. X-ray photoelectron spectroscopy (XPS) analysis of the nanostructures reveals the presence of Ti-O-In and In-O-In like species on the surface of nanostructures. Electron energy-loss spectroscopy (EELS) elemental mapping and EDX spectroscopy techniques combined with transmission electron microscope evidenced the existence of nanoheterostructures. XPS, EELS, EDX, and HAADF-STEM tools collectively suggest the presence of indium oxide nanoclusters like species on the surface of TiO2 nanostructures. These indium oxide nanocluster doped TiO2 (In2O3/T{001}) single crystals with {101} and {001} exposed facets exhibited 1.3 times higher visible light photocatalytic H2 production than indium oxide nanocluster doped TiO2 nanocrystals with only {101}facets (In2O3/T{101}) exposed. The remarkable photocatalytic activity of the obtained nanoheterostructures is attributed to the combined synergetic effect of indium oxide nanoclusters interacting with the titania surface, enhanced visible light response, high crystallinity, and unique structural features.