Advancements in transition bimetal catalysts for electrochemical 5-hydroxymethylfurfural(HMF) oxidation

The electrochemical oxidation of 5-hydroxymethylfurfural(HMF) represents a significant avenue for sustainable chemical synthesis, owing to its potential to generate high-value derivatives from biomass feedstocks. Transition metal catalysts offer a cost-effective alternative to precious metals for catalyzing HMF oxidation, with transition bimetallic catalysts emerging as particularly promising candidates. In this review, we delve into the intricate reaction pathways and electrochemical mechanisms underlying HMF oxidation, emphasizing the pivotal role of transition bimetallic catalysts in enhancing catalytic efficiency. Subsequently, various types of transition bimetallic catalysts are explored, detailing their synthesis methods and structural modulation strategies. By elucidating the mechanisms behind catalyst modification and performance enhancement, this review sets the stage for upcoming advancements in the field, ultimately advancing the electrochemical HMF conversion and facilitating the transition towards sustainable chemical production.

Electrolyte manipulation on Cu-based electrocatalysts for electrochemical CO_(2) reduction

Electrocatalytic reduction of CO_(2)is crucial for environmental sustainability and renewable energy storage,with Cu-based catalysts excelling in producing high-value C_(2+)products.However,a comprehensive analysis of how specific electrolyte influences Cu-based catalysts is lacking.This review addresses this gap by focusing on how electrolytes impact surface reconstruction and the CO_(2) reduction process on Cu-based electrocatalysts,identifying specific electrolyte compositions that enhance the density and stability of active sites,and providing insights into how different electrolyte environments modulate the selectivity and efficiency of C_(2+)product formation.The review begins by exploring how electrolytes induce favorable surface reconstruction in Cu-based catalysts,affecting surface roughness through dissolution-redeposition of Cu species and interactions with halogens and molecular additives.It also covers changes in crystalline facets of Cu and Cu_(2)O,and oxidation states,highlighting transitions from Cu^(0) to Cu^(δ+)and the stabilization of Cu^(+).The role of electrolytes in the C–C coupling process is examined,emphasizing their effects in modulating mass and charge transfer,CO_(2) adsorption,intermediate evolution,and product desorption.Subsequently,the mechanisms by non-aqueous electrolytes,including organic solvents,ionic liquids,and mixed electrolytes,affecting CO_(2) reduction are analyzed,highlighting the unique advantages and challenges of each type.The review concludes by addressing current challenges,proposing solutions,and research directions,such as optimizing electrolyte composition by integrating diverse cations and anions and employing advanced in-situ characterization techniques.These insights can significantly enhance CO_(2)reduction performance on Cu-based electrocatalysts,advancing efficient and sustainable green energy technologies.

Evaluating the feasibility and preliminary effects of an online compassion training program for nursing students:A pilot randomized controlled trial

Objectives:This study aimed to assess the feasibility of an online compassion training program for nursing students and preliminarily investigate its effects on mindfulness,self-compassion,and stress reduction.Methods:This study employed a randomized controlled trial design.Second-year students from a nursing college in Guangzhou,China,were recruited as research participants in August 2023.The intervention group participated in an 8-week online compassion training program via the WeChat platform,comprising three stages:mindfulness(weeks 1e2),self-compassion(weeks 3e5),and compassion for others(weeks 6 e8).Each stage included four activities:psychoeducation,mindfulness practice,weekly diary,and emotional support.Program feasibility was assessed through recruitment and retention rates,program engagement,and participant acceptability.Program effectiveness was measured with the Mindful Attention Awareness Scale,Self-Compassion Scale-Short Form,and Perceived Stress Scale.Results:A total of 28 students completed the study(13 in the intervention group,15 in the control group).The recruitment rate was 36.46%,with a high retention rate of 93.3%.Participants demonstrated high engagement:69.2%accessed learning materials every 1e2 days,93.3%practiced mindfulness at least weekly,with an average of 4.69 diary entries submitted per person and 23.30 WeChat interactions with instructors.Regarding acceptability,all participants expressed satisfaction with the program,with 92.4%finding it“very helpful”or“extremely helpful.”In terms of intervention effects,the intervention group showed a significant increase in mindfulness levels from pre-intervention(51.54±10.93)to postintervention(62.46±13.58)(P<0.05),while no significant change was observed in the control group.Although there were no statistically significant differences between the two groups in post-intervention self-compassion and perceived stress levels,the intervention group showed positive trends:selfcompassion levels increased(35.85±8.60 vs.40.85±5.54),and perceived stress levels slightly decreased(44.77±8.65 vs.42.00±5.77).Conclusions:This pilot study demonstrated the feasibility of an online compassion training program for nursing students and suggested its potential effectiveness in enhancing mindfulness,self-compassion,and stress reduction.Despite limitations such as small sample size and lack of long-term follow-up,preliminary evidence indicates promising prospects for integrating such training into nursing education.Further research is warranted to confirm thesefindings and assess the sustained impact of this approach on nursing education and practice.

Electrochemical creation of surface charge transfer channels on photoanodes for efficient solar water splitting

Electrochemical treatment is a popular and efficient method for improving the photoelectrochemical performance of water‐splitting photoelectrodes.In our previous study,the electrochemical activation of Mo‐doped BiVO_(4) electrodes was ascribed to the removal of MoO_(x) segregations,which are considered to be surface recombination centers for photoinduced electrons and holes.However,this proposed mechanism cannot explain why activated Mo‐doped BiVO_(4) electrodes gradually lose their activity when exposed to air.In this study,based on various characterizations,it is suggested that electrochemical treatment not only removes partial MoO_(x) segregations but also initiates the formation of H_(y)MoO_(x) surface defects,which provide charge transfer channels for photogenerated holes.The charge separation of the Mo‐doped BiVO_(4) electrode was significantly enhanced by these charge transfer channels.This study offers a new insight into the electrochemical activation of Mo‐doped BiVO_(4) photoanodes,and the new concept of surface charge transfer channels,a long overlooked factor,will be valuable for the development of other(photo)electrocatalytic systems.

Ultrathin 3D radial tandem‐junction photocathode with a high onset potential of 1.15 V for solar hydrogen production

Combining a progressive tandem junction design with a unique Si nanowire(SiNW)framework paves the way for the development of high‐onset‐potential photocathodes and enhancement of solar hydrogen production.Herein,a radial tandem junction(RTJ)thin film water‐splitting photo‐cathode has been demonstrated experimentally for the first time.The photocathode is directly fab‐ricated on vapor‐liquid‐solid‐grown SiNWs and consists of two radially stacked p‐i‐n junctions,featuring hydrogenated amorphous silicon(a‐Si:H)as the outer absorber layer,which absorbs short wavelengths,and hydrogenated amorphous silicon germanium(a‐SiGe:H)as the inner layer,which absorbs long wavelengths.The randomly distributed SiNW framework enables highly efficient light‐trapping,which facilitates the use of very thin absorber layers of a‐Si:H(~50 nm)and a‐SiGe:H(~40 nm).In a neutral electrolyte(pH=7),the three‐dimensional(3D)RTJ photocathode delivers a high photocurrent onset of 1.15 V vs.the reversible hydrogen electrode(RHE),accompanied by a photocurrent of 2.98 mA/cm^(2) at 0 V vs.RHE,and an overall applied‐bias photon‐to‐current effi‐ciency of 1.72%.These results emphasize the promising role of 3D radial tandem technology in developing a new generation of durable,low‐cost,high‐onset‐potential photocathodes capable of large‐scale implementation。

Molecular epidemiology demonstrates that imported and local strains circulated during the 2014 dengue outbreak in Guangzhou, China

The dengue virus （DENV） is a vital global public health issue. The 2014 dengue epidemic in Guangzhou, China, caused approximately 40,000 cases of infection and five deaths. We carried out a comprehensive investigation aimed at identifying the transmission sources in this dengue epidemic. To analyze the phylogenetics of the 2014 dengue strains, the envelope （E） gene sequences from 17 viral strains isolated from 168 dengue patient serum samples were sequenced and a phylogenetic tree was reconstructed. All 17 strains were serotype I strains, including 8 genotype I and 9 genotype V strains. Additionally, 6 genotype I strains that were probably introduced to China from Thailand before 2009 were widely transmitted in the 2013 and 2014 epidemics, and they continued to circulate until 2015, with one affinis strain being found in Singapore. The other 2 genotype I strains were introduced from the Malaya Peninsula in 2014. The transmission source of the 9 genotype V strains was from Malaysia in 2014. DENVs of different serotypes and genotypes co-circulated in the 2014 dengue outbreak in Guangzhou. Moreover, not only had DENV been imported to Guangzhou, but it had also been gradually exported, as the viruses exhibited an enzootic transmission cycle in Guangzhou.

Exploring facile strategies for high-oxidation-state metal nitride synthesis: carbonate-assisted one-step synthesis of Ta_3N_5 films for solar water splitting

Metal nitrides are widely studied due to their outstanding physical properties, including high hardness,high thermal and chemical stability, low electrical resistivity etc. Generally, metal nitrides can be obtained from the direct reaction of metal and ammonia/nitrogen. However, some of the metal nitrides,such as Ta_3N_5, cannot be synthesized by direct nitridation of metals. To achieve Ta_3N_5, high-oxidationstate Ta precursors like Ta_2O_5, NaTaO_3, TaS_3, K_6Ta_(10.8)O_(30), Ta(N(CH_3)_2)_5 and TaCl_5 have to be employed,which is a time-consuming and laborious process with the possibility of introducing undesirable impurities. Here taking Ta_3N_5 as an example, a facile carbonate-assisted one-step nitridation method is proposed, which enables the direct synthesis of high-oxidation-state metal nitride films from metal precursors under ammonia flow. The mechanism of the nitridation process has been studied, which carbon dioxide released from carbonates decomposition reacts with metallic Ta and assists the one-step conversion of metallic Ta to Ta_3N_5. The as-prepared Ta_3N_5 film, after modified with NiFe layered double hydroxide, exhibits promising water splitting performance and stability. This method avoids the preoxidation process of metal precursors in high-oxidation-state metal nitride synthesis, and may facilitate the direct fabrication of other important metal nitrides besides Ta_3N_5.

Reactive Inorganic Vapor Deposition of Perovskite Oxynitride Films for Solar Energy Conversion

The synthesis of perovskite oxynitrides,which are promising photoanode candidates for solar energy conversion,is normally accomplished by high-temperature ammonolysis of oxides and carbonate precursors,thus making the deposition of their planar films onto conductive substrates challenging.Here,we proposed a facile strategy to prepare a series of perovskite oxynitride films.Taking SrTaO_(2)N as a prototype,we prepared SrTaO_(2)N films on Ta foils under NH_(3) flow by utilizing the vaporized SrCl_(2)/SrCO_(3) eutectic salt.The SrTaO_(2)N films exhibit solar water-splitting photocurrents of 3.0 mA cm^(-2) at 1.23 V vs.RHE(reversible hydrogen electrode),which increases by 270%compared to the highest photocurrent(1.1 mA cm^(-2) at 1.23 V vs.RHE)of SrTaO_(2)N reported in the literature.This strategy may also be applied to directly prepare a series of perovskite oxynitride films on conductive substrates such as ATaO_(2)N(A=Ca,Ba)and ANbO_(2)N(A=Sr,Ba).

Curing the fundamental issue of impurity phases in two-step solution-processed CsPbBr3 perovskite films

Inorganic lead halide perovskite CsPbBr3 offers attractive photophysical properties and phase stability for high-performance optoelectronic devices.However,CsPbBr3 films produced by the classic solution-based two-step method are always accompanied with impurity phases of CsPb2Br5 and Cs4PbBr6,which represents a major efficiency-limiting factor for future advances of CsPbBr3-based devices.The challenge lies in the complexity of the Cs-Pb-Br phase system,requiring both spatially and temporally precise control of the precursor stoichiometry during solution-phase growth of CsPbBr3 films.By adopting 2-methoxyethanol as the solution conversion medium instead of commonly applied methanol,the reaction between CsBr and PbBr2 can be finely controlled to yield single phase CsPbBr3 films within a few minutes;extending the solution-conversion step to 24 h does not alter the phase purity of resulting CsPbBr3 films.The present work paves the way to regulate the crystal growth behaviors of two-step solution-processed CsPbBr3 films by simple solvent engineering.

Organics challenge inorganics for efficient photoelectrochemical water oxidation

Artificial photosynthesis provides a sustainable approach toward a carbon–neutral or net-zero economy[1].Photoelectrochemical(PEC)water splitting is one of the artificial photosynthesis techniques that directly convert intermittent sunlight into clean and storable H2 fuel[2].Due to the complex 4e-/4H+process coupled with O–O bond formation step,it is widely acknowledged that the oxidation half-reaction is the efficiency-limiting factor in water splitting[3].Therefore,developing highly efficient and robust water-oxidation photoanodes is crucial for realizing practical solar fuel production.

Centimeter-scale perovskite SrTaO2N single crystals with enhanced photoelectrochemical performance

Large-scale single crystals have potential applications in many fields,such as in ferroelectric and photoelectric energy conversion devices.Perovskite oxynitrides have also attracted attention in photoelectrochemical water splitting systems because of their high theoretical solar-to-hydrogen efficiencies.Nevertheless,the synthesis of perovskite oxynitride single crystals requires the coupling of cation exchange and ammonization processes,which is exceptionally challenging.The present study demonstrates an inorganic vapor method that provides,for the first time ever,high-quality epitaxial perovskite SrTaO_(2)N single crystals on the centimeter scale.Assessments using Raman spectroscopy,crystal structure analysis and density functional theory determined that the conversion mechanism followed a topotactic transition mode.Compared with conventional SrTaO_(2)N particle-assembled films,the SrTaO_(2)N single crystals made in this work were free of interparticle interfaces and grain boundaries,which exhibited extremely high performance during photoelectrochemical water oxidation.In particular,these SrTaO_(2)N single crystals showed the highest photocurrent density at 0.6 V vs.RHE(1.20 mA cm^(−2)) and the highest photocurrent filling factor(47.6%)reported to date,together with a low onset potential(0.35 V vs.RHE).This onset potential was 200 mV less than that of the reported in situ SrTaO_(2)N film,and the photocurrent fill factor was improved by 2 to 3 times.