Literature reviews establish the foundation of academic inquires. However, in the planning field, we lack rigorous systematic reviews. In this article, through a systematic search on the methodology ...of literature review, we categorize a typology of literature reviews, discuss steps in conducting a systematic literature review, and provide suggestions on how to enhance rigor in literature reviews in planning education and research.
Hierarchically dual‐mesoporous TiO2 microspheres have been synthesized by a solvothermal process in the presence of 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMImBF4) and diethylenetriamine ...(DETA) as co‐templates. Secondary mesostructured defects in the hierarchical TiO2 microspheres produce oxygen vacancies, which not only significantly enhance photocatalytic activity in the degradation of methylene blue (1.7 times that with P25) and acetone (2.9 times that with P25), but are also beneficial for lithium storage. Moreover, we propose a mechanism to rationalize the role of this dual mesoporosity of the TiO2 microspheres in enhancing molecular diffusion, ion transportation, and electronic transitions.
Beneficial dual mesoporosity: Hierarchically dual‐mesoporous TiO2 has been synthesized by a co‐templating method. Its mesostructured defects caused by an ionic liquid lead to a high level of oxygen vacancies (see graphic), which significantly enhance its photoelectrochemical performance.
Highly efficient light‐harvesting systems were successfully fabricated in aqueous solution based on the supramolecular self‐assembly of a water‐soluble pillar6arene (WP6), a salicylaldehyde azine ...derivative (G), and two different fluorescence dyes, Nile Red (NiR) or Eosin Y (ESY). The WP6‐G supramolecular assembly exhibits remarkably improved aggregation‐induced emission enhancement and acts as a donor for the artificial light‐harvesting system, and NiR or ESY, which are loaded within the WP6‐G assembly, act as acceptors. An efficient energy‐transfer process takes place from the WP6‐G assembly not only to NiR but also to ESY for these two different systems. Furthermore, both of the WP6‐G‐NiR and WP6‐G‐ESY systems show an ultrahigh antenna effect at a high donor/acceptor ratio.
Light‐harvesting systems were fabricated in aqueous solution by supramolecular self‐assembly of a water‐soluble pillar6arene (WP6), a salicylaldehyde azine derivative (G, acting as donor), and two different fluorescence dyes, Nile Red or Eosin Y. The dye is loaded within the WP6‐G assembly and acts as an acceptor.
An artificial light‐harvesting system with sequential energy‐transfer process was fabricated based on a supramolecular strategy. Self‐assembled from the host–guest complex formed by water‐soluble ...pillar5arene (WP5), a bola‐type tetraphenylethylene‐functionalized dialkyl ammonium derivative (TPEDA), and two fluorescent dyes, Eosin Y (ESY) and Nile Red (NiR), the supramolecular vesicles achieve efficient energy transfer from the AIE guest TPEDA to ESY. ESY can function as a relay to further transfer the energy to the second acceptor NiR and realize a two‐step sequential energy‐transfer process with good efficiency. By tuning the donor/acceptor ratio, bright white light emission can be successfully achieved with a CIE coordinate of (0.33, 0.33). To better mimic natural photosynthesis and make full use of the harvested energy, the WP5⊃TPEDA‐ESY‐NiR system can be utilized as a nanoreactor: photocatalyzed dehalogenation of α‐bromoacetophenone was realized with 96 % yield in aqueous medium.
It takes two to FRET: An artificial light‐harvesting system with a two‐step sequential energy‐transfer process in a relay mode was fabricated using a supramolecular strategy. It can be used as a nanoreactor for efficient photochemical catalysis. Moreover, bright white light emission can be successfully achieved with a CIE coordinate of (0.33, 0.33).
Thermal C-C bond cleavage reactions allow the construction of structurally diverse molecular skeletons via predictable and efficient bond reorganizations. Visible light photoredox-catalyzed ...radical-mediated C-C bond cleavage reactions have recently emerged as a powerful alternative method for overcoming the thermodynamic and kinetic barrier of C-C bond cleavage in diverse molecular scaffolds. In recent years, a plethora of elegant and useful reactions have been invented, and the products are sometimes otherwise inaccessible by classic thermal reactions. Considering the great influence and synthetic potential of these reactions, we provide a summary of the state of art visible light-driven radical-mediated C-C bond cleavage/functionalization strategies with a specific emphasis on the working models. We hoped that this review will be useful for medicinal and synthetic organic chemists and will inspire further reaction development in this interesting area.
A solvothermal method to prepare PtNi alloys that have differing morphologies is described. By adjusting the feed ratio of Pt and Ni precursors in this process, PtNi alloys with different ...compositions (Pt : Ni atomic ratio from 1 : 3 to 3 : 1) and morphologies (evolution from nanobranches to nanoparticles) are generated. The prepared Pt48Ni52 alloy, which has a composite morphology comprised of nanobranches and nanoparticles, exhibits superior activity and durability towards the hydrogen evolution reaction (HER) in seawater compared to those of commercial Pt/C catalyst and other PtNi alloys that have different compositions and morphologies. The excellent seawater HER performance of Pt48Ni52 is ascribed to its nanobranch/nanoparticle morphology that optimally facilitates electron accumulation on Pt, which enhances resistance to chloride corrosion in seawater.
Corrosion control: A PtNi alloy with a composite morphology comprised of nanobranches and nanoparticles is described. The unique morphology of the PtNi alloy facilitates electron accumulation on Pt, which enhances its resistance to chloride corrosion and performance in electrocatalytic hydrogen production in seawater.
Detection of nanoscale objects is highly desirable in various fields such as early‐stage disease diagnosis, environmental monitoring and homeland security. Optical microcavity sensors are renowned ...for ultrahigh sensitivities due to strongly enhanced light‐matter interaction. This review focuses on single nanoparticle detection using optical whispering gallery microcavities and photonic crystal microcavities, both of which have been developing rapidly over the past few years. The reactive and dissipative sensing methods, characterized by light‐analyte interactions, are explained explicitly. The sensitivity and the detection limit are essentially determined by the cavity properties, and are limited by the various noise sources in the measurements. On the one hand, recent advances include significant sensitivity enhancement using techniques to construct novel microcavity structures with reduced mode volumes, to localize the mode field, or to introduce optical gain. On the other hand, researchers attempt to lower the detection limit by improving the spectral resolution, which can be implemented by suppressing the experimental noises. We also review the methods of achieving a better temporal resolution by employing mode locking techniques or cavity ring up spectroscopy. In conclusion, outlooks on the possible ways to implement microcavity‐based sensing devices and potential applications are provided.
Single nanoparticle detection is of critical importance in various fields from fundamental research to practical applications. Optical microcavities are excellent candidates to be employed in ultra‐sensitive sensing due to significantly enhanced light‐matter interaction. The sensing performance can be improved by obtaining better spectral resolution and temporal resolution, and techniques can be applied to realize practical and portable sensors using microcavities.
Confinement of noble nanometals in a zeolite matrix is a promising way to special types of catalysts that show significant advantages in size control, site adjustment, and nano‐architecture design. ...The beauty of zeolite‐confined noble metals lies in their unique confinement effects on a molecular scale, and thus enables spatially confined catalysis akin to enzyme catalysis. In this Minireview, the confined synthesis strategies of zeolite‐confined noble metals will be briefly discussed, showing the processes, advantages, features, and mechanisms. The confined catalysis carried on zeolite‐confined noble metals will be summarized, and great emphasis will be paid to the confinement effects involving size, encapsulation, recognition, and synergy. Great progress of atomic sites in the size effect, supercage stabilization in the encapsulation effect, site adsorption in the recognition effect, and cascade reaction in the synergy effect are highlighted. This Minireview is concluded with challenges and opportunities in terms of the synthesis of zeolite‐confined noble metals and their applications to design multifunctional catalysts with high catalytic activity, selectivity, and stability.
The beauty of zeolite‐confined noble metals lies in their unique confinement effects on a molecular scale, and thus enables spatially confined catalysis akin to enzyme catalysis. This Minireview summarizes synthesis strategies and targeted catalysis applications for multifunctional zeolite‐confined noble metal catalysts.
An electrocatalyst composed of RuO2 surrounded by interfacial carbon, is synthesized through controllable oxidization‐calcination. This electrocatalyst provides efficient charge transfer, numerous ...active sites, and promising activity for pH‐universal electrocatalytic overall seawater splitting. An electrolyzer with this catalyst gives current densities of 10 mA cm−2 at a record low cell voltage of 1.52 V, and shows excellent durability at current densities of 10 mA cm−2 for up to 100 h. Based on the results, a mechanism for the catalytic activity of the composite is proposed. Finally, a solar‐driven system is assembled and used for overall seawater splitting, showing 95% Faraday efficiency.
An electrocatalyst composed of RuO2 surrounded by interfacial carbon is synthesized through controllable oxidization‐calcination. The interfacial carbon in RuO2/carbon compositions can provide efficient charge transfer and enhanced structural stability for the RuO2, which exhibits promising activity for pH‐universal electrocatalytic overall seawater splitting and its application in the solar‐driven electrolyzer.
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