Search

With the rapid development of science and technology and the steady recovery of the economy, rural ecotourism has become the first choice for many residents for tourism and entertainment. As an integral part of urban-rural integration planning, rural ecotourism can play a positive role in promoting the development of the township economy and farmers' entrepreneurship and employment. In recent years, rural ecotourism has been vigorously developed and promoted under the supportive policies and the high attention of local governments. Based on in-depth research on the comprehensive evaluation index system of sustainable development of rural tourism resources at home and abroad, this paper selects 15 3-level indicators from four aspects of management planning, economic development, environmental protection, and social value to evaluate the rural tourism in Huangqiao Town. A fuzzy comprehensive evaluation is carried out on the sustainable development level of resources. The evaluation results show that the comprehensive score of the sustainable development level of rural tourism resources in Huangqiao Town is "good," which indicates that Huangqiao Town pays more attention to the development and utilization of rural tourism resources. [ABSTRACT FROM AUTHOR]

Hybrid organic‐inorganic perovskite solar cells (PSCs) have become a shining star in the photovoltaic field due to their spectacular increase in power conversion efficiency (PCE) from 3.8 % to over 23 % in just few years, opening up the potential in addressing the important future energy and environment issues. The excellent photovoltaic performance can be attributed to the unique properties of the organometal halide perovskite materials, including high absorption coefficient, tunable bandgap, high defect tolerance, and excellent charge transport characteristics. The authors entered this field when pursuing research on dye‐sensitized solar cells (DSCs) by leveraging nanorods arrays for vectorial transport of the extracted electrons. Soon after, we and others realized that while the organometal halide perovskite materials have excellent intrinsic properties for solar cells, interface engineering is at least equally important in the development of high‐performance PSCs, which includes surface defect passivation, band alignment, and heterojunction formation. Herein, we will address this topic by presenting the historical development and recent progress on the interface engineering of PSCs primarily of our own group. This review is mainly focused on the material and interface design of the conventional n‐i‐p, inverted p‐i‐n and carbon electrode‐based structure devices from our own experience and perspective. Finally, the challenges and prospects of this area for future development will also be discussed. [ABSTRACT FROM AUTHOR]

The photoionization efficiency (PIE) spectra for niobium clusters up to Nb76 are measured using laser ionization time-of-flight mass spectrometry. Ionization potentials (IPs) assigned from the PIE spectra evolve with the same general pattern observed for other transition metal clusters (Mn) studied to date: a rapid yet nonmonotonic decrease in IP to n[bar_over_tilde:_approx._equal_to]15 followed thereafter by a relatively slow and smooth evolution. The measured IPs evolve with cluster radius R according to the predictions of the conducting spherical droplet model if the limiting (R→∞) IP is chosen to be 0.5 eV lower than the bulk polycrystalline work function. Kinetics experiments using D2 as the coreactant indicate the existence of two structural forms, one highly reactive, one relatively unreactive for clusters in the size range Nb9–Nb12, with the reactive forms predominant in each case. PIE spectra for Nb9–Nb12 were recorded using sufficient D2 added to the cluster source to selectively titrate the reactive forms of these clusters, leaving the unreactive forms as the predominant isomers. It is found that the unreactive forms of Nb9 and Nb12 possess higher IPs than those of the reactive forms, while both forms of Nb10 possess approximately the same IP. [ABSTRACT FROM AUTHOR]

The photoionization efficiency (PIE) spectra for cold iron clusters (Fe6–Fe90) and cobalt clusters (Co3, Co7–Co92) have been measured using a tunable ultraviolet laser combined with time-of-flight mass spectrometry. Vertical ionization potentials (IPs) assigned from the observed photoionization thresholds decrease rapidly but nonmonotonically for both Fen and Con up to n≅20, beyond which IPs evolve more slowly and smoothly. The measured IPs for both iron and cobalt clusters are lower than those predicted by the conducting spherical droplet model. The evolution of IP with increasing cluster radius R is observed to occur more gradually than the R-1dependence predicted by this model. This suggests that the Fermi energy for clusters in this size range decreases with increasing cluster size. The shapes of the PIE spectra near threshold are observed to continuously evolve with increasing cluster size, with the smallest clusters displaying photoionization efficiencies which rapidly increase with energy above threshold, and larger clusters displaying spectra with more gradual slopes. It is proposed that this trend reflects the evolution in the density and distribution of low-lying electronic states which occurs with increasing cluster size. [ABSTRACT FROM AUTHOR]

The threshold photoionization efficiency (PIE) curves for nickel clusters in the size range Ni3 to Ni90 have been measured by laser photoionization with detection by time-of-flight mass spectrometry. Both warm (≤298 K) and cold (≤77 K) clusters have been studied. The PIE curves for 298 K clusters display thermal tails, while these tails are smaller for cold clusters. Cluster ionization potentials (I.P.s) have been determined by two methods: the Watanabe procedure and linear extrapolation of the PIE curves. Dramatic dependence of I.P. on cluster size is found for clusters smaller than 11 atoms, while the I.P.s of larger clusters decrease relatively smoothly and nearly monotonically from 5.84 eV for Ni11 to 5.56 eV for Ni90. The I.P.s for clusters larger than Ni40 show the linear dependence on reciprocal radius (R-1) predicted by the conducting spherical drop model of small particle I.P.s, but do not fit the model quantitatively unless the limiting (R-1→ 0) work function is reduced by 0.46 eV from the bulk polycrystalline value. The differences between the thermal tails of the room temperature and 77 K PIE curves diminish with increasing cluster size, suggesting a reduced difference between neutral and ionic structures for larger clusters. In general, there is poor agreement between our experimental results and theoretically calculated I.P.s for small nickel clusters, with the exception of the recently reported tight-binding theory results of Pastor et al. [Chem. Phys. Lett. 148, 459 (1988)]. [ABSTRACT FROM AUTHOR]

The tsunami of research on halide perovskites over the last decade is sparked by the unexpected revelation of their singular properties, creating a new field of perovskite optoelectronics with great achievements. Soon recognized is the importance of perovskite–perovskite (pe–pe) interfaced structures with coherent interfaces on account of the ease with which to tailor perovskite semiconducting properties, and the prospect to inject new functions and boost device performance. There have been prominent developments in the pe–pe interfaced structures concerning their innovative construction strategies, distinctive properties, and interesting optoelectronic applications. This article provides an overview of recent advances on the pe–pe interfaced structures with a view to informing their rational design and guiding the improvement of the derivate devices. It begins with introduction of the structures, energy levels, band alignments, and ion migration pertaining to the pe–pe interfaced structures. Next, five synthetic approaches are systematically presented. Then, theories, simulations, and characterizations of the interfaced structures are discussed. This is followed by highlighting the distinctive applications of the pe–pe interfaced structures in solar cells, detectors, and light‐emitting diodes. Finally, the review is concluded by comprehensively summing up the key points covered and pointing out promising research directions along the line for future endeavors. [ABSTRACT FROM AUTHOR]

Although Ni(OH)2 is a promising electrode material for electrochemical capacitors on account of its high theoretical specific capacitance and low cost, its application has been hindered by the low measured specific capacitance and poor cycle stability often associated with low specific surface area and poor electrical conductivity. This study aims to develop an amorphous-precursor method to anchor Ni(OH)2 nanocrystals onto conductive graphene sheets. We demonstrate the ability to control the composition, size, and morphology of Ni(OH)2 nanocrystals on graphene sheets by combination with an Ostwald ripening process, which has allowed investigation on how such factors influence their performance if used as pseudocapacitor electrodes. It was found that the specific capacitance increased and then decreased as the ratio of reduced graphene oxide (RGO) to Ni(OH)2 increased; the sample that contained 5.2 wt % of RGO achieved the highest specific capacitance of 1804.0 F g−1 (based on the total composite mass) and 1902.9 F g−1 (based on the mass of Ni(OH)2), close to the theoretical value of Ni(OH)2 (2082 F g−1). With a given ratio of RGO to Ni(OH)2, the specific capacitance decreased as the Ni(OH)2 nanocrystal size increased. However, the cycling performance increased as the stability of Ni(OH)2 in the nanocomposites increased; the highest was achieved for the most stable Ni(OH)2 hexagonal nanoplates on RGO. In all, with appropriate optimization of the parameters of the materials, a good pseudocapacitor performance was achieved for the Ni(OH)2/RGO hybrid system in terms of both the specific capacitance and the cycling stability. [ABSTRACT FROM AUTHOR]

Genistein is a major isoflavone with known hormonal and tyrosine kinase-modulating activities. Genistein has been shown to promote the growth of estrogen receptor positive (ER+) MCF-7 cells. In ER-negative (ER−)/erbB-2-overexpressing (erbB-2+) cells, genistein has been shown to inhibit cell growth through its tyrosine kinase inhibitor activity. The effects of genistein on cell growth and tamoxifen response in ER+/erbB-2-altered breast cancers (known as luminal type B and noted in ∼10 to 20% of breast cancers) have not been well explored. Using erbB-2-transfected ER+ MCF-7 cells, we found that genistein induced enhanced cellular proliferation and tamoxifen resistance when compared with control MCF-7 cells. These responses were accompanied by increased phosphorylation of ERα and ER signaling, without increase in ER protein levels. Genistein-treated MCF-7/erbB-2 cells also showed enhanced activation/phosphorylation of erbB-2, Akt and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase. Blockade of the phosphatidylinositol 3-kinase and/or MAPK pathways abrogated genistein-induced growth promotion, suggesting that genistein effects involve both critical signaling pathways. We also found that p27/kip1 was markedly downregulated in genistein-treated MCF-7/erbB-2 cells. Overexpression of p27/kip1 attenuated genistein-mediated growth promotion. In aggregate, our data suggest that the concomitant coexpression of ER and erbB-2 makes breast cancers particularly susceptible to the growth-promoting effects of genistein across a wide range of doses. The underlying mechanisms involve enhanced ER–erbB-2 cross talk and p27/kip1 downregulation. [ABSTRACT FROM PUBLISHER]

Abstract: Genistein is a major soy isoflavone with multiple properties. The impact of soy genistein on breast cancer is controversial. One of the issues is whether soy genistein has a genotoxic effect at physiological concentrations. To address this question using an in vitro model, we first established MCF-10A/G0 and MCF-10A/G1 cell lines, which were MCF-10A cells exposed to 0.01% dimethyl sulfoxide (as vehicle control), i.e., MCF-10A/G0, or 1 μmol/L of genistein for 3 months, MCF-10A/G1, respectively. Chromosomal changes were compared between the two cell lines by routine G-banded chromosome analyses and both regular and array-based comparative genomic hybridization. After 3 months of exposure to genistein, the cell line MCF-10A/G1 showed loss of a normal chromosome 8 and gain of an extra chromosome 20, as well as loss of a chromosomal segment on the short arm of chromosome 9, leading to a homozygous deletion of the tumor suppressor genes CDKN2A (alias p16INK4a ) and CDKN2B (alias p15INK4b ). Our results suggest that long-term, low-concentration exposure to genistein may have the potential to induce chromosomal imbalances. These genotoxic effects may work in concert with other factors to induce genetic lesions that contribute to soy- and genistein-associated risk. [Copyright &y& Elsevier]

Abstract: Genistein, a soy isoflavone with anti-tumor properties, has both estrogenic and non-estrogenic activities. Genistein sensitive/estrogen receptor negative (ER-) MDA-MB-231 cells and genistein resistant/ER+MCF-7 cells are frequently cited as examples of differential responses to genistein due to different ER status. Other factors that may affect genistein response, however, are largely unknown. Based on our finding that MCF-7 is caspase-3 deficient, we examined whether caspase-3 status plays a role in the differential responses between the two cell lines. We demonstrate that reconstitution of caspase-3 significantly sensitizes MCF-7 cells to genistein. Specific knockdown of caspase-3 in MDA-MB-231 cells renders the cells resistant to genistein. We also found that caspases-4 and -10 were downregulated in MCF-7 cells. Reconstitution of caspase-10 in MCF-7 cells, however, resulted in little sensitization. Moreover, we show that caspase-3 downregulation is very common in breast cancer cell lines and tumor tissues. Taken together, our data indicate that caspase-3 is a critical determinant of cellular response to genistein, which may have important implications in studying soy/genistein-mediated anti-tumor activities. [Copyright &y& Elsevier]

Nanotechnology can be defined as the science and engineering involved in the design, synthesis and application of materials and devices on the nanometer scale. It is not in itself a single emerging discipline, but rather a meeting of several traditional sciences such as chemistry, physics, materials science, biology and engineering to bring together the required expertise needed to develop these new technologies. The unique properties of nanoscale materials provide benefits in remediation, pollution prevention, and efficient use of resources; however, the greatest contribution to green chemistry is likely to be the new manufacturing strategies available through nanoscience. So, the present review mainly focuses on the synthesis of semiconductor CuO nanomaterials from different starting materials by adopting various routes such as vapor-solid, vapor-liquid-solid, solid-liquid, etc. to reveal the morphological features of the precursor. [ABSTRACT FROM AUTHOR]

The photoionization efficiency (PIE) spectra and ionization potentials are reported for scandium cluster monoxides (ScO, n=5−36). As found for other transition metal clusters, strong dependence of ionization potential on cluster size is found for small clusters, with the ionization potentials of larger clusters decreasing relatively smoothly with increasing size. The IPs are 0.6-0.8 eV lower than that predicted by conducting spherical droplet model. [ABSTRACT FROM AUTHOR]

Describes a method of high-yield separation of metallofullerenes with other metal atoms encaged such as Pr@C82 and Pr2@C80. Absorption spectra of the metallofullerenes; Existence of Pr atoms inside the carbon cages in a cationic form represented by Pr3+; Evidence for spin-spin interaction; Intensity ratio of the major peak to the satellite peak in the XPS pattern of Pr@C82.

We have reproduced kinetics results indicating that niobium clusters in the size range Nb9–Nb12 are produced in two isomeric forms which possess widely different rates reactivity toward D2. We have exploited this difference in reactivity to record photoionization efficiency spectra of the unreactive forms of Nb9, Nb10, and Nb12 as well of a mixture containing predominantly the reactive forms. We find that the photoionization thresholds measured for Nb9 and Nb12 with the reactive forms of these species depleted via reaction with D2 are shifted to higher energies compared those recorded without D2 present. The photoionization threshold energies for both unreactive and reactive forms of Nb10 are approximately equal. [ABSTRACT FROM AUTHOR]

Defects formed at the surface, buried interface and grain boundaries (GB) of CsPbI 3 perovskite films considerably limit photovoltaic performance. Such defects could be passivated effectively by the most prevalent post modification strategy without compromising the photoelectric properties of perovskite films, but it is still a great challenge to make this strategy comprehensive to different defects spatially distributed throughout the films. Herein, a spatially selective defect management (SSDM) strategy is developed to roundly passivate various defects at different locations within the perovskite film by a facile one-step treatment procedure using a piperazine-1,4-diium tetrafluoroborate (PZD(BF 4) 2) solution. The small-size PZD2+ cations could penetrate into the film interior and even make it all the way to the buried interface of CsPbI 3 perovskite films, while the BF 4 − anions, with largely different properties from I− anions, mainly anchor on the film surface. Consequently, virtually all the defects at the surface, buried interface and grain boundaries of CsPbI 3 perovskite films are effectively healed, leading to significantly improved film quality, enhanced phase stability, optimized energy level alignment and promoted carrier transport. With these films, the fabricated CsPbI 3 PSCs based on carbon electrode (C-PSCs) achieve an efficiency of 18.27%, which is among the highest-reported values for inorganic C-PSCs, and stability of 500 h at 85 °C with 65% efficiency maintenance. [ABSTRACT FROM AUTHOR]

Tin halide perovskites (THPs) have demonstrated exceptional potential for various applications owing to their low toxicity and excellent optoelectronic properties. However, the crystallization kinetics of THPs are less controllable than its lead counterpart because of the higher Lewis acidity of Sn2+, leading to THP films with poor morphology and rampant defects. Here, a colloidal zeta potential modulation approach is developed to improve the crystallization kinetics of THP films inspired by the classical Derjaguin‐Landau‐Verwey‐Overbeek (DLVO) theory. After adding 3‐aminopyrrolidine dihydro iodate (APDI2) in the precursor solution to change the zeta potential of the pristine colloids, the total interaction potential energy between colloidal particles with APDI2 could be controllably reduced, resulting in a higher coagulation probability and a lower critical nuclei concentration. In situ laser light scattering measurements confirmed the increased nucleation rate of the THP colloids with APDI2. The resulting film with APDI2 shows a pinhole‐free morphology with fewer defects, achieving an impressive efficiency of 15.13 %. [ABSTRACT FROM AUTHOR]

CsPbI3 perovskite is a promising light absorber in perovskite solar cells (PSCs) due to its suitable bandgap (Eg) and high chemical stability, but the perovskite phase is metastable in ambient atmosphere and prone to defect formation. To enhance phase stability and reduce defects, forming a low dimensional (LD) perovskite on CsPbI3 has proved effective. However, the energy levels for most of low‐conductivity LD perovskites are not very compatible with those of CsPbI3, which will impair charge separation and device performance. Herein, a new 1D perovskite (5‐Azaspiro[4.4]nonan‐5‐ium lead triiodide, ASNPbI3) with compatible energy levels and a large Eg is reported as a capping layer. The p‐type ASNPbI3 forms a p‐n heterojunction with n‐CsPbI3 with a staggered band alignment, considerably enhancing the carrier separation. Besides, by pre‐forming a ASNPbI3 at an intermediate stage, defects are suppressed in perovskite film. Consequently, the CsPbI3 PSCs based on carbon electrode without hole transporter (C‐PSCs) achieves a PCE of 18.34%, which is among the highest‐reported values for inorganic C‐PSCs. Furthermore, the hydrophobic ASNPbI3 capping layer has a high thermal stability that greatly enhances perovskite phase stability. Hence, the CsPbI3 C‐PSCs maintains 68% of its initial PCE after 400 h aging at 85°C in a N2 glovebox. [ABSTRACT FROM AUTHOR]

Tin halide perovskites (THPs) have demonstrated exceptional potential for various applications owing to their low toxicity and excellent optoelectronic properties. However, the crystallization kinetics of THPs are less controllable than its lead counterpart because of the higher Lewis acidity of Sn2+, leading to THP films with poor morphology and rampant defects. Here, a colloidal zeta potential modulation approach is developed to improve the crystallization kinetics of THP films inspired by the classical Derjaguin‐Landau‐Verwey‐Overbeek (DLVO) theory. After adding 3‐aminopyrrolidine dihydro iodate (APDI2) in the precursor solution to change the zeta potential of the pristine colloids, the total interaction potential energy between colloidal particles with APDI2 could be controllably reduced, resulting in a higher coagulation probability and a lower critical nuclei concentration. In situ laser light scattering measurements confirmed the increased nucleation rate of the THP colloids with APDI2. The resulting film with APDI2 shows a pinhole‐free morphology with fewer defects, achieving an impressive efficiency of 15.13 %. [ABSTRACT FROM AUTHOR]

Cost‐effective non‐noble metal‐based catalysts for selective hydrogenation with excellent activity, selectivity, and durability are still the holy grail. Herein, an oxygen‐doped carbon (OC) chainmail encapsulated dilute Cu–Ni alloy is developed by simple pyrolysis of Cu/Ni‐metal–organic framework. The CuNi0.05@OC catalyst displays superior performance for atmospheric pressure transfer hydrogenation of p‐chloronitrobenzene and p‐nitrophenol, and for hydrogenation of furfural, all in water and with exceptional durability. Comprehensive characterizations confirm the close interactions between the diluted Ni sites, the base Cu, and optimized three‐layered graphene chainmail. Theoretical calculations demonstrate that the properly tuned lattice strain and Schottky junction can adjust electron density to facilitate specific adsorption on the active centers, thus enhancing the catalytic activity and selectivity, while the OC shell also offers robust protection. This work provides a simple and environmentally friendly strategy for developing practical heterogeneous catalysts that bring the synergistic effect into play between dilute alloy and functional carbon wrapping. [ABSTRACT FROM AUTHOR]

Zeolite microspheres have been successfully applied in commercial-scale separators such as oxygen concentrators. However, further enhancement of their applications is hampered by the post-synthetic shaping process that formulates the zeolite powder into packing-sized spherical bodies with various binders leading to active site blockage and suboptimal performance. Herein, binderless zeolite microspheres with a tunable broad size range from 2 µm to 500 µm have been developed with high crystallinity, sphericity over 92%, monodispersity with a coefficient of variation (CV) less than 5%, and hierarchical pore architecture. Combining precursor impregnation and steam-assisted crystallization (SAC), mesoporous silica microspheres with a wide size range could be successfully transformed into zeolite. For preserved size and spherical morphology, a judicious selection of the synthesis conditions is crucial to ensure a pure phase, high crystallinity, and hierarchical architecture. For the sub-2-µm zeolite microsphere, low-temperature prolonged aging was important so as to suppress external zeolization that led to a large, single macroporous crystal. For the large 500 µm sphere, ultrasound pretreatment and vacuum impregnation were crucial and facilitated spatially uniform gel matrix dispersion and homogenous crystallization. The obtained zeolite 5A microspheres exhibited excellent air separation performance, while the 4A microspheres displayed ammonium removal capabilities. This work provides a general strategy to overcome the existing limitations in fabricating binder-free technical bodies of zeolites for various applications. [ABSTRACT FROM AUTHOR]

Precisely regulating surface reconstruction of copper (Cu) chalcogenides‐based catalysts to promote the multicarbon (C2+)selectivity of the electrochemical CO2 reduction reaction (CO2RR) is hampered by the challenging control of the intractable anions and the optimal Cuδ+ reduction (0 < δ < 1). Herein, a porous carbon‐supported copper selenides electrocatalyst that can remarkably improve the C2‐product yield and especially unveil the time‐revolved electrochemical CO2RR reconstruction process to enable the high C2‐selectivity, most notably for ethanol is constructed. The Faradic efficiency (FE) of C2‐products achieved is as high as ≈85.2% with a partial current density of 229.5 mA cm−2. Operando infrared spectroscopy and density functional theory (DFT) calculations unravel that the surface Se vacancies (VSe) formation brings closer the neighboring Cu+ atoms and activates the Cu sites, thereby rendering efficient generation of the key intermediates (*CO and *CHO) and lowering the C–C coupling barrier for C2 production. The appearance of metallic Cu can shorten the next‐nearest Cu0–Cu+ distance for O atom to bridge in, leading to the preferential formation of *OC2H4 towards ethanol instead of C–O bond cleavage to form ethylene. This work opens the avenue of designing suitable local atomic structures catalysts to engage the intermediates for targeted CO2RR products. [ABSTRACT FROM AUTHOR]

Single‐crystalline metal halide perovskite, due to its large X‐ray attenuation coefficient, high carrier mobility, and facile fabrication properties, is considered as a promising candidate material for direct X‐ray detectors. Despite the rapid development of high‐sensitivity perovskite detectors, their practical application is still hindered by their high dark current levels and the lack of effective approach for assembling the perovskite photodetectors on thin‐film transistor (TFT) backplane. Herein, it is shown that, by using a supersaturated 2D perovskite precursor as a wet‐fusing intermedia, a high‐performance 2D/3D perovskite detector can be fabricated and simultaneously attached to the TFT backplane. The assembled 2D/3D heterostructure perovskite detector shows low dark current density, high sensitivity, and low dose detection limit. This work provides a viable route to realize a low‐dose, high‐resolution direct X‐ray image sensor based on perovskite photodetectors. [ABSTRACT FROM AUTHOR]

Ion migration has been regarded as one of the most interesting and mysterious processes in halide‐perovskite‐based electronic devices. On the one hand, ion migration contributes to the hysteresis and poor stability problems of perovskite devices. On the other hand, the mobile ions can passivate the interfaces of perovskite devices, leading to improved carrier transportation and collection. This article gives a critical review on the ion migration in halide perovskite materials. It starts with a brief introduction of the origin and nature of the ion migration problem in perovskite materials. Next, the electric, photoelectric, and structural phenomena resulting from ion migration and their influence on the performance and stability of the perovskite devices are focused on. The recent literature work on the characterization of ion migration is reviewed and the characterization techniques are highlighted. Furthermore, different approaches that can suppress the ion migration process are also introduced. Finally, ion migration in the emerging all‐inorganic halide perovskite materials is compared with that in hybrid halide perovskite materials, and the implications on device design and performance are discussed. [ABSTRACT FROM AUTHOR]

The photoinduced reactions of the complexes Mg[sup +]–SCNC[sub 2]H[sub 5] and Mg[sup +]–NCSC[sub 2]H[sub 5] are studied comparatively in the spectral range of 230–440 nm. One-photon excitation of the complexes through the Mg[sup +] chromophore (3 [sup 2]P←3 [sup 2]S) gives rise to the evaporative fragment as well as the molecular activation and charge transfer products. The action spectra of the complexes consist of three broad peaks for Mg[sup +]–SCNC[sub 2]H[sub 5] and two for Mg[sup +]–NCSC[sub 2]H[sub 5], which accord with the structures obtained from quantum mechanics calculations. These calculations reveal two association isomers for Mg[sup +]–SCNC[sub 2]H[sub 5]: one is with Mg[sup +] being linked to the S atom and the other to the N atom. The former is more stable than the latter by only 0.23 eV. Both of the isomers have been shown to exist in the complex source employed in our experiments. On the other hand, only one stable structure is found for the complex Mg[sup +]–NCSC[sub 2]H[sub 5] characterized by the Mg[sup +]–N linkage. In general, the photofragments are dominated by Mg[sup +] at λ>400 nm, which decreases with decreasing wavelength accompanied by the increase in other photoproducts. In addition, the branching ratios of Mg[sup +] to other photoproducts are nearly constant in the short wavelength region but decrease with decreasing wavelength. The observed photoreactions have been reasonably explained. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Photoinduced reactions in Mg[sup +]-NH[sub 2]CH[sub 3] and Mg[sup +] - NH(CH[sub 3])[sub 2] have been studied in the spectral range of 230-440 nm. Although the N-H bond activation channel was found to be prominent in the photodissociation of Mg[sup +] - NH[sub 3] [Yoshida, Okai, and Fuke, Chem. Phys. Lett. 347, 93 (2001)], it is very unfavorable as the ammonia is replaced by methylamines in the complex. Instead, C-H bond cleavage products are observed from Mg[sup +] - NH[sub 2]CH[sub 3](CH[sub 2]NH[sub 2, sup +]) and exclusively produced from Mg[sup +] - NH(CH[sub 3])[sub 2]((CH[sub 3])HN[sup +] = CH[sub 2]) after photoexcitation. For Mg[sup +] - NH[sub 2]CH[sub 3], the C-N bond activation product Mg[sup +]NH[sub 2] and the charge transfer product CH[sub 3]NH[sub 2, sup +] are also abundant. The action spectra of the complexes consist of two pronounced peaks on the red and blue side of the Mg[sup +] 3 ²P ← 3 ²S atomic transition. The calculated absorption spectra of the two complexes using the optimized structures of their ground states are in good agreement with the observed action spectra. On the basis of the branching fraction data and the calculated complex structures, the C-H bond activation is invoked to account for the MgH loss channel after photoexcitation, followed by a nonadiabatic transition to the ground state by a bond-stretch mechanism. However, the formation of Mg[sup +]NH[sub 2] from photodissociation of Mg[sup +] - NH[sub 2]CH[sub 3] involves the insertion of Mg[sup +] into the C-N bond. Finally, the photoinduced charge transfer product CH[sub 3]NH[sub 2, sup +] are also identified from Mg[sup +] - NH[sub 2]CH[sub 3] but not from Mg[sup +] - NH(CH[sub 3])[sub 2]. [ABSTRACT FROM AUTHOR]

We induced the intra-complex reactions in Mg[sup +]-2,2,2-trifluoroethanol by photons in the spectral region of 240-410 nm. We observed the nonreactive channel product Mg[sup +] and a number of reactive channel products throughout the whole excitation region. The reactive photoproducts originate from the scission of the C-O or C-F bond, as well as from the simultaneous rupture of both bonds. The action spectrum consists of two broad peaks between the atomic transition of Mg[sup +](3[sup 2]p←3[sup 2]S). Ab initio calculations show a minimum-energy structure, in which Mg[sup +] attaches to the O atom and one of the three F atoms of 2,2,2-trifluoroethanol, forming a five-membered ring. The calculated absorption spectrum corresponding to the minimum-energy structure agrees nicely with the experimental action spectrum. The branching fractions of the photoproducts are approximately constant in a given spectral range, but they change significantly across the spectral ranges. The constant branching fractions point to the ground state reactions following traversals from the initially accessed excited states through conical intersections. On the other hand, the observation of the electronic state-specific branching fractions is explained by the orbital alignments of the excited electron, which is dictated by the five-membered ring structure of the complex. [ABSTRACT FROM AUTHOR]

We present the photodissociation spectroscopy of the complexes of Mg[sup +] with di- and tri-ethylamine in the spectral range of 230–440 nm. Mass spectrometry of the two parent complexes exhibits the persistent product Mg[sup +] from nonreactive quenching throughout the whole wavelength range. As for the reactive channels, C[sub 3]H[sub 7][sup •]-elimination products are dominant when the complexes are excited to 3P[sub x,y]. Furthermore, photoexcitation of Mg[sup +]–NH(C[sub 2]H[sub 5])[sub 2] to 3P[sub x,y] yields a minor MgH-elimination fragment. On the other hand, photodissociation of Mg[sup +]–N(C[sub 2]H[sub 5])[sub 3] produces charge-transfer fragments N[sup +](C[sub 2]H[sub 5])[sub 3] and (C[sub 2]H[sub 5])[sub 2]N[sup +]CH[sub 2]. The action spectra of the two complexes consist of two pronounced peaks on the red and blue side of the Mg[sup +] 3 [sup 2]P←3 [sup 2]S atomic transition. The calculated absorption spectra of the two complexes using the optimized structures of their ground states agree nicely with the observed action spectra. Photofragment branching fractions of the products are shown to be nearly independent of the photon energy for the 3P[sub x,y] excitation, indicating the importance of exit channel effects. A photoreaction mechanism is proposed for C[sub 3]H[sub 7][sup •]-elimination, which entails Mg[sup +] insertion into one C–N bond, followed by a nonadiabatic transition to the ground-state surface through a conical intersection. However, for the MgH-elimination channel in the photodissociation of Mg[sup +]–NH(C[sub 2]H[sub 5])[sub 2], Mg[sup +] rather inserts into the α-C–H bond. Finally, photoexcitation of Mg[sup +]–N(C[sub 2]H[sub 5])[sub 3] leads to a prominent charge-transfer product [N[sup +](C[sub 2]H[sub 5])[sub 3]][sup *], which dissociates further to (C[sub 2]H[sub 5])[sub 2]N[sup +]CH[sub 2] by a loss of CH[sub 3][sup •]. © 2002 Ameri... [ABSTRACT FROM AUTHOR]

Pristine fullerene C60 is an excellent electron transport material for state‐of‐the‐art inverted structure perovskite solar cells (PSCs), but its low solubility leaves thermal evaporation as the only method for depositing it into a high‐quality electron transport layer (ETL). To address this problem, we herein introduce a highly soluble bowl‐shaped additive, corannulene, to assist in C60‐assembly into a smooth and compact film through the favorable bowl‐ball interaction. Our results show that not only corannulene can dramatically enhance the film formability of C60, it also plays a critical role in forming C60‐corannulene (CC) supramolecular species and in boosting intermolecular electron transport dynamics in the ETL. This strategy has allowed CC devices to deliver high power conversion efficiencies up to 21.69 %, which is the highest value among the PSCs based on the solution‐processed‐C60 (SP‐C60) ETL. Moreover, the stability of the CC device is far superior to that of the C60‐only device because corannulene can retard and curb the spontaneous aggregation of C60. This work establishes the bowl‐assisted ball assembly strategy for developing low‐cost and efficient SP‐C60 ETLs with high promise for fully‐SP PSCs. [ABSTRACT FROM AUTHOR]

Pristine fullerene C60 is an excellent electron transport material for state‐of‐the‐art inverted structure perovskite solar cells (PSCs), but its low solubility leaves thermal evaporation as the only method for depositing it into a high‐quality electron transport layer (ETL). To address this problem, we herein introduce a highly soluble bowl‐shaped additive, corannulene, to assist in C60‐assembly into a smooth and compact film through the favorable bowl‐ball interaction. Our results show that not only corannulene can dramatically enhance the film formability of C60, it also plays a critical role in forming C60‐corannulene (CC) supramolecular species and in boosting intermolecular electron transport dynamics in the ETL. This strategy has allowed CC devices to deliver high power conversion efficiencies up to 21.69 %, which is the highest value among the PSCs based on the solution‐processed‐C60 (SP‐C60) ETL. Moreover, the stability of the CC device is far superior to that of the C60‐only device because corannulene can retard and curb the spontaneous aggregation of C60. This work establishes the bowl‐assisted ball assembly strategy for developing low‐cost and efficient SP‐C60 ETLs with high promise for fully‐SP PSCs. [ABSTRACT FROM AUTHOR]

Halide perovskite narrowband photodetectors based on a charge collection narrowing mechanism have emerged as a new class of optoelectronic devices for monochromatic imaging. However, improving the figures‐of‐merit of such narrowband photodetectors remains challenging due to the inability to manipulate the major material players in the elusive photoresponse process. Here, a novel approach of manipulating ion migration to enhance the narrowband photoresponse of self‐driven p‐i‐n type photodetectors is taken by intentionally adding mobile ions into the formamidine and methylamine mixed cation perovskite layer. The excess mobile ions reduce the activation energy of ion migration, and this facilitated migration orchestrates the ions in the perovskite layer to re‐engineer the energy band, and thus modulates the charge separation and collection energetics and kinetics, leading to an unprecedented boost of the narrowband photoresponse. The photodetector based on this approach achieved a peak responsivity of as high as 112.41 mA W−1 at 820 nm at zero bias with a full‐width at half maximum of only 22 nm and an over 3‐fold improvement in the spectral rejection ratio, making it highly promising for the next‐generation color imaging devices. [ABSTRACT FROM AUTHOR]

Reports on photofragmentation studies of small selenium cluster cations. Detection of the parent and daughter cluster ions using a reflectron time-of-flight mass spectrometer; Estimating the appearance potentials of all the observed cluster fragment ions; Decrease in dissociation thresholds of the odd-numbered cations with the increase in cluster size.

The one-color resonant two-photon ionization technique is employed to study jet-cooled van der Waals (vdW) clusters of halobenzene and nitrogen through the S0→S1 transition around the 000 band. The spectra obtained exhibit rich information about the clusters’ intermolecular vdW vibrational modes and their solvent internal rotation. We have tentatively assigned all the observed spectral features to a single isomer of C6H5X···N2 (X=F, Cl, Br). The influence of X on the vdW vibrations and the internal rotation of N2 in the complex is investigated. The analysis of the influence of X on the 000 spectral shift suggests that the change in vdW interaction energy upon electronic excitation is mainly due to the dispersion term. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Reactions of excimer laser (XeCl, 308 nm) vaporized and excited fullerene C60 with La, Y, Eu, and Gd were carried out in mixtures of C60/La2O3, C60/Y2O3, C60/Eu2O3, and C60/Gd2O3. The reaction products M[ATOTHER]@xa[/ATOTHER]C60, M[ATOTHER]@xa[/ATOTHER]C60-2n and M[ATOTHER]@xa[/ATOTHER]C60+2m (M=La, Y, Eu, and Gd) were identified by a reflectron type time-of-flight mass spectrometer (RTOFMS). The products were subjected to reactions with H2O, O2, and N2O in a pick-up source. The metallofullerenes were found to be nonreactive toward H2O, N2O, and O2. This gives support to the endohedral nature of the metallofullerenes. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

van der Waals complexes Nam...(XR)n (R=CH3 and Ph; X=Cl and F) have been generated by crossing a beam of Na with a supersonic jet of halide molecules XR seeded with Ar. The complexes were identified and measured by photoionization time-of-flight mass spectrometry. Tunable visible radiation (530–680 nm) was used to measure the photodissociation spectrum (an ‘‘action spectrum’’) of these clusters. The peak cross section for photodissociation of Na2...(ClCH3)n (n=1 and 2) was found to be large (∼6 Å2) with its maximum at 635 nm for n=1 and at 615 nm for n=2. These peak wavelengths suggest that the primary route for photodissociation is excitation of the Nam followed by charge-transfer dissociation: Na2...(ClCH3)1,2 + hυ → [Na*2...(ClCH3)1,2]‡ → [Na+2...(ClCH3)1,2-]‡→products (the double dagger indicates a transition state). By contrast, the photodissociation of Na2+...(ClCH3) appeared to follow a direct mechanism involving the dissociation of the [Na–Na]+. For Na...FPh, two excited states of the complex (Π and Σ) were thought to be responsible for the two broad peaks in the action spectrum, each with vibrational structure. [ABSTRACT FROM AUTHOR]

Highlights: Trace amounts of long-chain gemini surfactants are essential for blade-coating of high-quality perovskite films, enabling a 17.05% efficient full printed carbon-based module (50 cm2 active area). Only when the surfactant chain is over a critical length will the gemini surfactant be effective for blade-coating of perovskite films. The surfactants increase the capillary number of perovskite precursor solution, reduce the local disturbance and combat inhomogeneous solidification during blade coating, thus allowing high-quality perovskite films to be formed. Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in ambient air. However, scaling up to high-efficiency carbon-based solar modules hinges on reliable deposition of uniform defect-free perovskite films over large areas, which is an unsettled but urgent issue. In this work, a long-chain gemini surfactant is introduced into perovskite precursor ink to enforce self-assembly into a network structure, considerably enhancing the coverage and smoothness of the perovskite films. The long gemini surfactant plays a distinctively synergistic role in perovskite film construction, crystallization kinetics modulation and defect passivation, leading to a certified record power conversion efficiency of 15.46% with Voc of 1.13 V and Jsc of 22.92 mA cm−2 for this type of modules. Importantly, all of the functional layers of the module are printed through a simple and high-speed (300 cm min−1) blade coating strategy in ambient atmosphere. These results mark a significant step toward the commercialization of all-printable carbon-based perovskite solar modules. [ABSTRACT FROM AUTHOR]

Abstract: Organic‐inorganic halide perovskite materials have become a shining star in the photovoltaic field due to their unique properties, such as high absorption coefficient, optimal bandgap, and high defect tolerance, which also lead to the breathtaking increase in power conversion efficiency from 3.8% to over 22% in just seven years. Although the highest efficiency was obtained from the TiO2 mesoporous structure, there are increasing studies focusing on the planar structure device due to its processibility for large‐scale production. In particular, the planar p‐i‐n structure has attracted increasing attention on account of its tremendous advantages in, among other things, eliminating hysteresis alongside a competitive certified efficiency of over 20%. Crucial for the device performance enhancement has been the interface engineering for the past few years, especially for such planar p‐i‐n devices. The interface engineering aims to optimize device properties, such as charge transfer, defect passivation, band alignment, etc. Herein, recent progress on the interface engineering of planar p‐i‐n structure devices is reviewed. This review is mainly focused on the interface design between each layer in p‐i‐n structure devices, as well as grain boundaries, which are the interfaces between polycrystalline perovskite domains. Promising research directions are also suggested for further improvements. [ABSTRACT FROM AUTHOR]

We demonstrate the construction of heterojunction arrays for boosting solar water splitting by combining in situ guided growth of heterointerfaces and energy band tuning. By directly growing an ultrathin Fe2WO6 layer on a preformed WO3 nanosheet array in full coverage, a uniform and dense array of intimately contacted WO3/Fe2WO6 heterojunction was created. The heterojunction array shows not only a largely broadened visible light absorption range but also a built-in interface polarization to accelerate hole transfer from WO3 to Fe2WO6. Meanwhile, fine-tuning to match energy levels at the heterojunction was achieved by doping WO3 with Fe (Fe-WO3), leading to improved electrical conductivity and reduced charge recombination. Photoanodes based on such heterojunction arrays have shown significantly enhanced photoelectrochemical (PEC) water splitting performance, clearly arising from the above-mentioned efforts. Furthermore, by decorating FeOOH/NiOOH cocatalysts on the heterojunction arrays in tandem, the surface water oxidation kinetics was considerably accelerated, and the resulting Fe-WO3/Fe2WO6/FeOOH/NiOOH photoanode achieved a photocurrent density of 2.78 mA/cm2 at 1.23 V vs reversible hydrogen electrode. This work highlights the benefits of in situ construction of heterojunction arrays for enhancing the PEC performance. [ABSTRACT FROM AUTHOR]

Tunable local surface plasmon resonance (LSPR) enhancement properties of scaffold-based multi-nanoparitcle clusters were investigated using finite-difference time-domain (FDTD) method with calculated optical spectra, near-field distribution, and average enhancement of hybrid nanostructures as slab/nanoparticls, cylinder/nanoparticles, and sphere/nanoparticles. Focusing on influence factors including surface curvature, coupling effect, and decorated particle number, several models were built for further understanding on the dominate contribution in complicate multi-particle nanostructure and to explore their potential for plasmonic enhancement applications such as surface-enhanced Raman spectroscopy (SERS), solar cells material, LSPR sensor, and nanoantenna. [ABSTRACT FROM AUTHOR]

Highlights: The nanocorn design enables In2O3-x@C a high Faradaic efficiency of 98% and a high formate current density of 320 mA cm−2 at a low potential of -1.2 V versus hydrogen electrode without iR correction. The rich O vacancy activates In3+ sites on the nanocube shell of In2O3-x@C and the carbon cob enhances conductivity. Operando X-ray absorption spectroscopy unveils the active site of In3+ for formate production although reduction of In3+ to In is conceivable at the applied negative potentials during CO2 reduction reaction.For electrochemical CO2 reduction to HCOOH, an ongoing challenge is to design energy efficient electrocatalysts that can deliver a high HCOOH current density (JHCOOH) at a low overpotential. Indium oxide is good HCOOH production catalyst but with low conductivity. In this work, we report a unique corn design of In2O3-x@C nanocatalyst, wherein In2O3-x nanocube as the fine grains dispersed uniformly on the carbon nanorod cob, resulting in the enhanced conductivity. Excellent performance is achieved with 84% Faradaic efficiency (FE) and 11 mA cm−2JHCOOH at a low potential of − 0.4 V versus RHE. At the current density of 100 mA cm−2, the applied potential remained stable for more than 120 h with the FE above 90%. Density functional theory calculations reveal that the abundant oxygen vacancy in In2O3-x has exposed more In3+ sites with activated electroactivity, which facilitates the formation of HCOO* intermediate. Operando X-ray absorption spectroscopy also confirms In3+ as the active site and the key intermediate of HCOO* during the process of CO2 reduction to HCOOH. [ABSTRACT FROM AUTHOR]

Focuses on a study which examined photoinduced charge-transfer dissociation in van der Waals complexes. Photochemistry of metal-halide complexes; Details of photodepletion action spectra for sodium; Laser photoionization time-of-flight mass spectrum of sodium.

We report the preparation of highly monodisperse ZnO nanoparticles using poly(vinyl pyrrolidone) (PVP) as the capping molecules. The surface-modified ZnO nanoparticles were found to be remarkably stable. The optical absorption shows distinct excitonic features. Markedly enhanced near-band-edge ultraviolet photoluminescence and significantly reduced defect-related green emission were also observed. We attribute this observation to the nearly perfect surface passivation of the ZnO nanoparticles by the PVP molecules. The third-order nonlinear optical response of these PVP-capped ZnO nanoparticles in a dilute solution was found to be significantly larger (by at least two orders of magnitude) than that of the bulk ZnO. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Post‐treatment is a widely used strategy to reduce defects in perovskite films, but has been largely limited to the solution phase. Herein, the posttreatment tool kit and develop a universal amine salts (AIXI) vapor healing strategy by taking advantage of the penetrating power of vapor and the soft‐matter characteristics of halide perovskite is expanded. In a striking demonstration, the post‐treatment of pristine perovskite layers allows simultaneous filling of the MA+ and I– vacancies, passivation of both the cation and anion defects, and healing of the films to high order and high crystallinity required for high device performance, from the surface to the bulk and all the way down to the bottom. Experiments and DFT calculations revealed that charge extraction can be enhanced and non‐radiative recombination can be reduced by regulating the energy levels and reducing the trap states via the AIXI vapor healing. Moreover, the diffusing AIXI can reach the NiOx surface to obstruct the undesirable interfacial reactions and passivate the interface defects, further reducing the open‐circuit voltage (Voc) loss. The vapor healing strategy substantially reduces the trap density from 4.76 × 1015 to 1.04 × 1015 cm–3, and promots power conversion efficiency of the champion device from 17.92% to 20.48% with superior device consistency, Voc up to 1.114 V and the operational device stability. [ABSTRACT FROM AUTHOR]

Living organisms are imparted with compact intelligence in which a myriad of functionalities are delivered by highly integrated and demodularized subunits, as in the case of the mammalian skin in which different embedding stimuli‐receptors and follicles work together to provide rich sensation for temperature and tactility, as well as the visible and regulatory response of hair erection via the arrector pili muscle. A breakthrough in robotics is to create similar intelligence using emerging stimuli‐responsive materials. Here, a thin film composite comprising a transition metal oxide/hydroxide layer for sensation and high‐performing actuation under environmental stimuli including visible light, humidity, and temperature, and a graphene‐based layer for feedback strain sensing, is developed to demonstrate such an approach of robotics. The system is used to construct robotic hair that mimics well mammalian hair in functionality, and devices for sensing objects for their effective manipulation. This research opens a "material intelligence" approach for robotics. [ABSTRACT FROM AUTHOR]

Halide perovskites are intensively studied for applications in optoelectronic devices because of their outstanding properties and relatively low cost. However, the common precursor solutions for perovskite fabrication are rather unstable in the presence of moisture and oxygen, limiting the large‐scale low‐cost production of perovskite. Herein, water is used counterintuitively to formulate an ambient stable perovskite precursor, which is peculiar in that it is solid at room temperature but becomes a liquid at 75 °C. The non‐fluidity of the precursor stemmed from the water‐assisted intermediate fiber assembly, conferring high damp air stability. Yet the heat‐liquefiability made the precursor highly processible for perovskite growth, and when guided by polyvinyl pyrrolidone coordination with Pb2+, the perovskite can preferentially grow along the [200] direction, significantly improving the film quality. To demonstrate the utility of the precursor, it has been used to fabricate self‐driven halide perovskite photodetectors, which exhibited a low noise current of 2.0 × 10−14 A Hz−1/2, a high specific detectivity up to 1.4 × 1013 Jones, and high stability of 20 days of operation with only < 5% external quantum efficiency decay. This type of solid‐liquid convertible precursor opens up new opportunities for wider applications of perovskites. [ABSTRACT FROM AUTHOR]

There is increasing evidence that defects such as oxygen vacancies are a double‐edged sword for photoelectrochemical (PEC) water splitting. Although surface oxygen vacancies can largely improve the catalytic activity, their bulk counterparts may bind polarons, drag down the carrier transport, and thus degrade the PEC performance. However, it is very challenging to precisely control the spatial and energy distributions of defects. Instead, the infrared part of sunlight, normally discarded in PEC water splitting, is harvested to thermally activate the polarons. With the prototypical BiVO4 photoanode (absorbs blue–ultraviolet light), even when is undoped, a high solar‐to‐hydrogen efficiency of 5.3% is achieved in conjunction with a photothermal substrate (absorbs infrared light) and in tandem with a perovskite solar cell (absorbs red–green). Detailed characterizations reveal that the temperature increase of the system can not only accelerate the polaron hopping, but also activate the polarons bound by defects. This study, by demonstrating the use of the PEC‐inactive infrared part of sunlight to enhance transport kinetics at the device level, allows for panchromatic sunlight harvesting to improve the overall PEC performance. [ABSTRACT FROM AUTHOR]

By changing the ratios of two cationic surfactants, cetyltrimethylammonium bromide (CTAB) and cetyltrimethylammonium chloride (CTAC), irregular quasi-spherical AuNPs, popcorn-shaped AuNPs, ricepaper pith shaped AuNPs and the spinous-like Au nanostructures were synthesized via a convenient seed-mediated method. The composition of the as-prepared uniform Au nanostructure was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The differences in shape and kinetics mechanism were well explained by morphological changes arising from using different ratios of the two surfactants. Systematical analysis revealed that the generation of Au nanostructures with different shapes, including different degrees of curvature of the tips and the differences in shape strongly depended on controlling the ratios of the two surfactants which further affect their localized surface plasmon resonance (LSPR) properties in both visible and near-infrared regions. Moreover, the spinous-like Au nanostructures showed obvious surface-enhanced Raman scattering activity for crystal violet (CV) dye, which implied that the irregular quasi-spherical AuNPs, popcorn-shaped AuNPs, rice paper pith shaped AuNPs and the spinous-like Au nanostructures could be used in applications such as electronics, catalysis, and imaging. [ABSTRACT FROM AUTHOR]

Elucidating the facet-dependent photocatalytic activity of semiconductor photocatalysts is important in improving the overall efficiency of photocatalysis. Furthermore, combining facet control with selective deposition of oxidation and/or reduction cocatalysts on specific faces of semiconductor photocatalysts is potentially an effective strategy to synergistically optimize the functionality of photocatalysts. In the present study, high-purity wurtzite-type β-AgI platelet microcrystals with polar {0001} facets were prepared by a facile polyvinylpyrrolidone-assisted precipitation reaction. The polar-faceted AgI microplates were used as archetypes to demonstrate preferential diametric migration (i.e., effective separation) of photogenerated electrons and holes along the c axis. Such vectorial electron-hole separation stems from the asymmetric surface structures, which give rise to distinct photoexcited reaction behaviors on the ±(0001) polar facets of wurtzite-type semiconductors. Furthermore, on selective deposition of Ag and MnO x (1.5< x<2) cocatalysts on the reductive (0001) and oxidative (000 $\bar 1$) facets, respectively, photocatalytic activity of the AgI microplates in degrading organic pollutants was dramatically enhanced thanks to the broad light-absorption range, strong dye-adsorption ability, and effective spatial separation of photocarriers. [ABSTRACT FROM AUTHOR]

We report on the development of highlyconductive NiCo2S4single crystalline nanotubearrays grown on a flexiblecarbon fiber paper (CFP), which can serve not only as a good pseudocapacitivematerial but also as a three-dimensional (3D) conductive scaffoldfor loading additional electroactive materials. The resulting pseudocapacitiveelectrode is found to be superior to that based on the sibling NiCo2O4nanorod arrays, which are currently used insupercapacitor research due to the much higher electrical conductivityof NiCo2S4. A series of electroactive metaloxide materials, including CoxNi1–x(OH)2, MnO2, and FeOOH, weredeposited on the NiCo2S4nanotube arrays byfacile electrodeposition and their pseudocapacitive properties wereexplored. Remarkably, the as-formed CoxNi1–x(OH)2/NiCo2S4nanotube array electrodes showed the highestdischarge areal capacitance (2.86 F cm–2at 4 mAcm–2), good rate capability (still 2.41 F cm–2at 20 mA cm–2), and excellent cyclingstability (∼4% loss after the repetitive 2000 cycles at a charge–dischargecurrent density of 10 mA cm–2). [ABSTRACT FROM AUTHOR]

The ever-increasing energy consumption stimulated the development of various solar energy conversion systems. Photocathodic protection (PCP), emerges as a promising photoelectrochemical technology to alleviate metal corrosion, but the centralization of all core reaction steps on one photoelectric-conversion-unit induces extremely low energy conversion efficiencies. Herein, a proof-of-concept modular PCP device incorporating electron transport layer (ETL), photoelectric conversion layer (PCL), hole transport layer (HTL) and hole consumption layer (HCL) is fabricated to delocalize the key reaction steps for the first time. Such a unified ETL/PCL/HTL/HCL architecture facilitates the efficient extraction of photoexcited electrons from the small-gap PCL to the protected metal through ETL, and holes to HCL for water oxidization through HTL. The directional "macroscopic" charge migration, prolonged charge lifetime and accelerated water oxidation lead to significantly improved PCP effectiveness in simulated seawater. Our findings provide a groundbreaking PCP design, allowing fine-tuning individual functional modules and inter-modular interfaces to vastly elevate performance. [Display omitted] • A photocathodic protection system with multi-module architecture was fabricated. • The key photoelectrochemical reaction steps were delocalized to separate modules. • The directional charge flow was maintained through the whole unified device. • Vastly improved energy conversion efficiency than conventional design was achieved. • A groundbreaking design strategy for photocathodic protection systems is provided. [ABSTRACT FROM AUTHOR]