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Ensuring information security has emerged as a paramount concern in contemporary human society. Substantial advancements in this regard can be achieved by leveraging photonic signals as the primary information carriers, utilizing photonic logical gates capable of wavelength tunability across various time and spatial domains. However, the challenge remains in the rational design of materials possessing space‐time‐color multiple‐resolution capabilities. In this work, a facile approach is proposed for crafting metal‐organic halides (MOHs) that offer space‐time‐color resolution. These MOHs integrate time‐resolved room temperature phosphorescence and color‐resolved excitation wavelength dependencies with both space‐resolved ex situ optical waveguides and in situ heterojunctions. Capitalizing on these multifaceted properties, MOHs‐based two‐dimensional (2D) optical waveguides and heterojunctions exhibit the ability to tune full‐color emissions across the spectra from blue to red, operating within different spatial and temporal scales. Therefore, this work introduces an effective methodology for engineering space‐time‐color resolved MOH microstructures, holding significant promise for the development of high‐density photonic logical devices. [ABSTRACT FROM AUTHOR]

Glycerol, as the major by-product of biodiesel, is a highly versatile molecule with three similar hydroxyl groups. Recently, great efforts have been made to find active catalysts and suitable catalytical technology to convert it into various valuable fine chemicals. Catalytic oxidation of glycerol via renewable sources of solar energy have attracted much attention because of the unique reaction pathway induced by photogenerated reactive species as well as the mild reaction conditions required. In this review, we describe the recent development of selective oxidation pathways for conversion of glycerol to value-added chemicals via photocatalysis and photoelectrocatalysis, specifically, how to realize C–OH bond oxidation to C＝O with other functional groups preserved, and C–C bond cleavage and oxidation to carboxyl, –COOH. Particular emphasis is paid to the design of catalyst active structures in the given reaction pathways, including semiconductors with specific adsorption sites, surface plasmon resonance metals, transition metal complex cocatalysts, and synergy with photongenerated reactive oxygen species (ROS). Therefore, this review provides an in-depth understanding of the mechanisms for selective oxidation of glycerol via photocatalysis/photoelectrocatalysis as important guidance for the design of efficient catalysts. [ABSTRACT FROM AUTHOR]

Molecule-based room-temperature-phosphorescence (RTP) materials have received much attention recently. For future optical displays and image applications, the development of ordered RTP thin films is highly important, but the fabrication of such RTP films is much more difficult than that of RTP crystals, and examples are still quite limited. In this work, we confirm that the direct layer-by-layer assembly of a small RTP molecule (DBT) and polyvinyl alcohol (PVA) can be achieved based on hydrogen bonding interaction. The films not only exhibit tunable RTP light-emitting colors upon UV photostimulation at 254 nm and 365 nm, but also exhibit direct white-light-emitting polarized phosphorescence due to the ordered micro/nanostructure of the RTP films. Moreover, the highly enhanced RTP quantum yields and lifetimes upon increasing assembly cycles can be assigned to the strong Fermi coupling between DBT and PVA in the films. It is anticipated that the incorporation of other RTP molecules in flexible polymers based on the ordered LBL assembly can be utilized to fabricate a range of new smart RTP film materials. [ABSTRACT FROM AUTHOR]

Abstract: The development of durable, low‐cost, and efficient photo‐/electrolysis for the oxygen and hydrogen evolution reactions (OER and HER) is important to fulfill increasing energy requirements. Herein, highly efficient and active photo‐/electrochemical catalysts, that is, CoMn‐LDH@g‐C3N4 hybrids, have been synthesized successfully through a facile in situ co‐precipitation method at room temperature. The CoMn‐LDH@g‐C3N4 composite exhibits an obvious OER electrocatalytic performance with a current density of 40 mA cm−2 at an overpotential of 350 mV for water oxidation, which is 2.5 times higher than pure CoMn‐LDH nanosheets. For HER, CoMn‐LDH@g‐C3N4 (η50=−448 mV) requires a potential close to Pt/C (η50=−416 mV) to reach a current density of 50 mA cm2. Furthermore, under visible‐light irradiation, the photocurrent density of the CoMn‐LDH@g‐C3N4 composite is 0.227 mA cm−2, which is 2.1 and 3.8 time higher than pristine CoMn‐LDH (0.108 mA cm−2) and g‐C3N4 (0.061 mA cm−2), respectively. The CoMn‐LDH@g‐C3N4 composite delivers a current density of 10 mA cm−2 at 1.56 V and 100 mA cm−2 at 1.82 V for the overall water‐splitting reaction. Therefore, this work establishes the first example of pure CoMn‐LDH and CoMn‐LDH@g‐C3N4 hybrids as electrochemical and photoelectrochemical water‐splitting systems for both OER and HER, which may open a pathway to develop and explore other LDH and g‐C3N4 nanosheets as efficient catalysts for renewable energy applications. [ABSTRACT FROM AUTHOR]

The mechanical properties and thermostability of poly(vinyl alcohol) (PVA) nanofiber mats have been obviously improved by the incorporation of sodium chloride (NaCl). The tensile properties including tensile strength and modulus of membranes with an addition of 1.0 wt % NaCl increased from 2.51 to 4.22 MPa and 33.0 to 176.30 MPa, respectively, more than 160 and 700% of those of the electrospun pure PVA membranes. Moreover, thermogravimetric analysis showed that the initial decomposition temperature (Ti) and the half decomposing temperature (T50%) of PVA nanofibers with the addition of NaCl were at least 26 and 59 °C higher than that of pure PVA nanofibers, respectively, indicating a strong interaction between the PVA and the salt ions. [ABSTRACT FROM AUTHOR]