Manipulating energy migration in nanoparticles toward tunable photochromic upconversion.

Smart control of energy interactions plays a key role in manipulating upconversion dynamics and tuning emission colors for lanthanide-doped materials. However, quantifying the energy flux in particular energy migration in the representative sensitizer-activator coupled upconversion system has remained a challenge. Here we report a conceptual model to examine the energy flux in a single nanoparticle by designing an interfacial energy transfer mediated nanostructure.

Visible light-activated polyphenol-Al coordination for ambient and quantitative xylose-to-furfural conversion.

Bio-based xylose-to-furfural conversion is often accompanied by condensation/degradation at evaluated thermal conditions. This study presents a combined strategy of visible light-enhanced acidity and local photothermal effect for room-temperature cascade isomerization-dehydration of xylose to furfural in an ultrahigh yield (96.3%), in which Lewis acidic Al centers facilitate electron transfer from xylose to initiate isomerization and the formation of Al-polyphenol complex is enabled to release Brønsted acid for dehydration while co-added bio-graphene offers satisfactory photothermal conditions.

Interfacial Thermoconvection and Atomic Relay Catalysis Enable Equilibrium Shifting and Rapid Glucose-to-Fructose Isomerization.

The aqueous glucose-to-fructose isomerization is controlled by thermodynamics to an equilibrium limit of ~50 % fructose yield. However, here we report an in situ fructose removal strategy enabled by an interfacial local photothermal effect in combination with relay catalysis of geminal and isolated potassium single atoms (K SAs) on graphene-type carbon (K/GT) to effectively bypass the equilibrium limit and markedly speed up glucose-to-fructose isomerization. At 25 °C, an unprecedented fructose yield of 68.

Visible Light-Switchable Lattice Oxygen Sites for Selective C-H and C(O)-C Bond Electrooxidation.

Lattice-oxygen is highly oxidizable, ideal for electrocatalytic C-H oxidation but insufficient alone for C(O)-C bond cleavage due to the non-removable nature of lattice sites. Here, we present a visible light-assisted electrochemical method of in situ formulating removable lattice-oxygen sites in a nickel-oxyhydroxide (ESE-NiOOH) electrocatalyst. This catalyst efficiently converts aromatic alcohols and carbonyls with C(O)-C fragments from lignin and plastics into benzoic acids (BAs) with high yields (83-99 %).

Enabling Multimodal Luminescence in a Single Nanoparticle for X-ray Imaging Encryption and Anticounterfeiting.

Multimodal luminescent materials hold great promise in a diversity of frontier applications. However, achieving the multimodal responsive luminescence at the single nanoparticle level, especially besides light stimuli, has remained a challenge. Here, we report a conceptual model to realize multimodal luminescence by constructing both mechanoluminescence and photoluminescence in a single nanoparticle.

High-efficiency photocatalytic CO reduction enabled by interfacial Ov and isolated Ti of g-CN/TiO Z-scheme heterojunction.

Exploring the real force that drives the separation of Coulomb-bound electron-hole pairs in the interface of heterojunction photocatalysts can establish a clear mechanism for efficient solar energy conversion efficiency. Herein, the formation of oxygen vacancy (Ov) and isolated Ti was precisely regulated at the interface of g-CN/TiO Z-scheme heterojunction (g-CN/Ov-Ti-TiO) by optimizing the opening degree of the calcination system, showing excellent production rate of CO and CH from CO photoreduction under visible light. This photocatalytic system also exhibited prominent stability.

Spatiotemporal control of photochromic upconversion through interfacial energy transfer.

Dynamic control of multi-photon upconversion with rich and tunable emission colors is stimulating extensive interest in both fundamental research and frontier applications of lanthanide based materials. However, manipulating photochromic upconversion towards color-switchable emissions of a single lanthanide emitter is still challenging. Here, we report a conceptual model to realize the spatiotemporal control of upconversion dynamics and photochromic evolution of Er through interfacial energy transfer (IET) in a core-shell nanostructure.

Cross Relaxation Enables Spatiotemporal Color-Switchable Upconversion in a Single Sandwich Nanoparticle for Information Security.

Smart control of ionic interaction dynamics offers new possibilities for tuning and editing luminescence properties of lanthanide-based materials. However, it remains a daunting challenge to achieve the dynamic control of cross relaxation mediated photon upconversion, and in particular the involved intrinsic photophysics is still unclear. Herein, this work reports a conceptual model to realize the color-switchable upconversion of Tm through spatiotemporal control of cross relaxation in the design of NaYF:Gd@NaYbF:Tm@NaYF sandwich nanostructure.

Photocatalytic C-N bond construction toward high-value nitrogenous chemicals.

The construction of carbon-nitrogen bonds is vital for producing versatile nitrogenous compounds for the chemical and pharmaceutical industries. Among developed synthetic approaches to nitrogenous chemicals, photocatalysis is particularly prominent and has become one of the emerging fields due to its unique advantages of eco-sustainable characteristics, efficient process integration, no need for high-pressure H, and tunable synthesis methods for developing advanced photocatalytic materials. Here, the review focuses on potential photocatalytic protocols developed for the construction of robust carbon-nitrogen bonds in discrepant activation environments to produce high-value nitrogenous chemicals.

Novel supramolecular deep eutectic solvent-enabled in-situ lignin protection for full valorization of all components of wheat straw.

Lignin is usually deemed as an inhibitor to enzymatic hydrolysis of cellulose due to its physical barrier, non-productive adsorption, and steric hindrance. Herein, a novel supramolecular deep eutectic solvent (SUPRADES), comprising ethylene glycol and citric acid in 5:1 M ratio, and β-cyclodextrin (β-CD) in a concentration of 3.5% (w/w), was developed to be efficient for pretreating wheat straw.

Tunable and Efficient Photoluminescence of Lanthanide-Doped CsNaScCl Double Perovskite Single Crystals toward Multifunctional Light-Emitting Diode Applications.

Lead-free halide double perovskite, as one of the promising candidates for lead halide perovskite materials, shows great potential in light-emitting diodes (LEDs), benefiting from its environmental friendliness and high chemical stability. However, the poor regulation of the emission spectra severely limits its application range. Herein, various lanthanide ions were successfully doped in CsNaScCl double perovskite single crystals (DPSCs) to yield effective and stable emissions spanning from visible to near-infrared (NIR) regions.

Selectively Manipulating Interactions between Lanthanide Sublattices in Nanostructure toward Orthogonal Upconversion.

Smart control of ionic interactions is a key factor to manipulate the luminescence dynamics of lanthanides and tune their emission colors. However, it remains challenging to gain a deep insight into the physics involving the interactions between heavily doped lanthanide ions and in particular between the lanthanide sublattices for luminescent materials. Here we report a conceptual model to selectively manipulate the spatial interactions between erbium and ytterbium sublattices by designing a multilayer core-shell nanostructure.

Multi-wavelength excitable mid-infrared luminescence and energy transfer in core-shell nanoparticles for nanophotonics.

2 μm mid-infrared (MIR) light sources have shown great potential for broad applications in molecular spectroscopy, eye-safe lasers, biomedical systems and so on. However, previous research studies were mainly focused on conventional materials such as glasses, glass-ceramics and crystals, limiting the luminescence intensity and miniaturization of photonic devices. Here we report a new strategy to realize the multiple excitation wavelength responsive MIR emission in a single nanoparticle by employing an erbium sublattice as the sensitizing host.

Photothermal technique-enabled ambient production of microalgae biodiesel: Mechanism and life cycle assessment.

Thermocatalytic (trans)esterification of oils/lipids to produce biodiesel is generally energy-consuming, reversible, and controlled by the equilibrium law. Herein, a light-induced photothermal process was illustrated to be highly efficient for biodiesel production (96.8 % yield) from microalgae lipids at room temperature enabled by a biomass-based SOH-functionalized graphene-like heterogeneous catalyst (S-NGL-600), as optimized by response surface methodology.

Oxidative C-C bond cleavage of lignin electrocatalysis.

Lignin, which is an important component of biomass in nature and is constantly produced in industry, becomes potential raw material for sustainable production of fine chemicals and biofuels. Electrocatalysis has been extensively involved in the activation of simple molecules and cleavage-recasting of complex scaffolds in an elegant environment. As such, electrocatalytic cleavage of C-C(O) in -O-4 model molecules of lignin to value-added chemicals has received much attention in recent years.

Efficient and tunable photoluminescence for terbium-doped rare-earth-based CsNaYCl double perovskite.

Lead-free double perovskite materials with efficient and stable self-trapped exciton (STE) emissions show enormous potential for next-generation solid-state lighting. However, the low-emission efficiency and difficulty of spectral regulation are two major obstacles to their application. Here, all-inorganic rare-earth-based double perovskite CsNaYCl single crystals with strong blue emissions were reported as effective hosts to accommodate lanthanide ion doping.

Multichannel Control of PersL/Upconversion/Down-Shifting Luminescence in a Single Core-Shell Nanoparticle for Information Encryption.

Persistent luminescence (PersL) has been attracting substantial attention in diverse frontier applications such as optical information security and in vivo bioimaging. However, most of the reported PersL emissions are based on the dopants instead of the host matrix, which also plays an important role. In addition, there are few works on the PersL-based multifunctional nanoplatform in nanosized materials.

Activating Ultrahigh Thermoresponsive Upconversion in an Erbium Sublattice for Nanothermometry and Information Security.

Thermal activation of upconversion luminescence in nanocrystals opens up new opportunities in biotechnology and nanophotonics. However, it remains a daunting challenge to achieve a smart control of luminescence behavior in the thermal field with remarkable enhancement and ultrahigh sensitivity. Moreover, the physical picture involved is also debatable.

Switching the NIR upconversion of nanoparticles for the orthogonal activation of photoacoustic imaging and phototherapy.

Phototheranostics based on upconversion nanoparticles (UCNPs) offer the integration of imaging diagnostics and phototherapeutics. However, the programmable control of the photoactivation of imaging and therapy with minimum side effects is challenging due to the lack of ideal switchable UCNPs agents. Here we demonstrate a facile strategy to switch the near infrared emission at 800 nm from rationally designed UCNPs by modulating the irradiation laser into pulse output.

Research Progress on the Photo-Driven Catalytic Production of Biodiesel.

Biodiesel considered a green, environmentally friendly, and renewable energy source is one of the most promising candidates to replace fossil fuels to supply energy for the world. The conventional thermocatalytic methods have been extensively explored for producing biodiesel, while inevitably encountering some drawbacks, such as harsh operating conditions and high energy consumption. The catalytic production of biodiesel under mild conditions is a research hotspot but with difficulty.

Reductive Upgrading of Biomass-Based Levulinic Acid to γ-Valerolactone Over Ru-Based Single-Atom Catalysts.

With the great adjustment of world industrialization and the continuous improvement of energy consumption requirements, the selective conversion of biomass-based platform molecules to high-value chemicals and biofuels has become one of the most important topics of current research. Catalysis is an essential approach to achieve energy-chemical conversion through the "bond breaking-bond formation" principle, which opens a broad world for the energy sector. Single-atom catalysts (SACs) are a new frontier in the field of catalysis in recent years, and exciting achievements have been made in biomass energy chemistry.

A Highly Effective Biomass-Derived Solid Acid Catalyst for Biodiesel Synthesis Through Esterification.

Efficient valorization of renewable liquid biomass for biodiesel production using the desirable biomass-based catalysts is being deemed to be an environmentally friendly process. Herein, a highly active biomass-based solid acid catalyst (SiO@Cs-SOH) with renewable chitosan as raw material through sulfonation procedure under the relatively mild condition was successfully manufactured. The SiO@Cs-SOH catalyst was systematically characterized, especially with a large specific surface area (21.

Ultrasensitive Thermochromic Upconversion in Core-Shell-Shell Nanoparticles for Nanothermometry and Anticounterfeiting.

Upconversion nanoparticle based ratiometric nanothermometry has shown many advantages including high relative sensitivity, fast temperature response, and high spatial resolution. However, most of the existing designs are on the basis of thermally coupled upconversion emissions, and it remains a challenge to improve the thermo-sensitivity. Here, we report a new nanoplatform of NaYF:Yb/Er/Ce@NaYF@NaYF:Yb/Tm core-shell-shell nanostructure to improve the thermal sensitivity through the nonthermally coupled upconversion emissions.

Controlling upconversion in emerging multilayer core-shell nanostructures: from fundamentals to frontier applications.

Lanthanide-based upconversion nanomaterials have recently attracted considerable attention in both fundamental research and various frontier applications owing to their excellent photon upconversion performance and favourable physicochemical properties. In particular, the emergence of multi-layer core-shell (MLCS) nanostructures offers a versatile and powerful tool to realize well-defined matrix compositions and spatial distributions of the dopant on the nanometer length scale. In contrast to the conventional nanomaterials and commonly investigated core-shell nanoparticles, the rational design of MLCS nanostructures allows us to deliberately introduce more functional properties into an upconversion system, thus providing unprecedented opportunities for the precise manipulation of energy transfer channels, the dynamic control of upconversion processes, the fine tuning of switchable emission colours and new functional integration at a single-particle level.