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This paper discusses the challenges and solutions for zinc–air batteries in practical mass production applications and provides a more reasonable structure for zinc–air power batteries.

As the basis of land resource allocation and land use planning, land-use functions (LUFs) are important indicators for evaluating the sustainable development of land and environments. It is essential to evaluate the LUFs of a specific area from the perspective of land-use comprehensive functions. This paper takes 38 districts and counties in Chongqing, China, as an example to construct a state-space model from three aspects, production factors, living factors, and ecological factors, which affect the functions of land resources. The paper continues to construct an evaluation index system and determine indicators by entropy methods to calculate and evaluate the spatial differentiation of land-use functions in Chongqing. The results show that the value of land-use multi-functions in Chongqing can be divided into three levels. The results are characterized by the gradual weakening of the main urban area and the polarization effect is strong. The distribution characteristics of this result are caused by the differences in traffic conditions, geographical location, the quality of natural conditions, economic levels, planning policies, etc. In the end, this paper proposes relative suggestions for the facet of eco-friendly production and development to strengthen future policy guidance. Future studies can continue to improve the index system and study the spatio-temporal effects of LUFs from a microscopic perspective to make the results more accurate.

Particle size governs the geometric and electronic structure of metal nanoparticles (NPs), shaping their catalytic performance. However, size-dependent entanglement in the geometric and electronic structures often leads to a trade-off between activity and selectivity, limiting the optimization of the overall catalytic performance. Here we show that precisely controlled deposition of a platinum monolayer on large gold NPs breaks the activity–selectivity trade-off on particle size in platinum-catalysed chemoselective hydrogenation of halonitrobenzenes, resulting in a remarkable activity, along with a 99% selectivity for haloanilines under mild conditions. The high activity results from upshift of the platinum 5d-band centre through platinum lattice expansion and ligand effect, whereas the high selectivity is caused by exposing more terrace sites on large particles. The geometric and electronic properties of bimetallic monolayer materials, distinct from monometallic NPs and alloys, constitute a promising platform for the rational design of metal catalysts with superior performance in hydrogenation reactions. Chemoselective reactions are often characterized by an activity–selectivity trade-off that renders their optimization difficult. Here gold nanoparticles equipped with a platinum monolayer are introduced that, thanks to lattice expansion and ligand effect, achieve a remarkable performance for the chemoselective hydrogenation of halonitrobenzenes

Sustainable methanol production via CO2 hydrogenation leads to increased interest in the understanding of active phase of Cu/ZnO/Al2O3 (CZA) catalyst. Model catalysts of ZnO/Cu(111) with structures varied from two-dimensional planar to three-dimensional nanoparticles were prepared by atomic layer deposition (ALD) method. By combing scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS) at near-ambient pressure of CO2 hydrogenation, we reveal that the submonolayer ZnO/Cu(111) transformed into Cu-Zn alloy under 10 mbar CO2/H2 at 493 K, and underwent a partial re-oxidation during evacuation. The dynamic phase transformation of ZnO/Cu(111) may partly explain the existence of differences and apparently contradictory theories to account for the origin of active phase in CZA catalysts.

For supported metal catalysts, the underlying support not only disperses and stabilizes metal particles, but also modulates their electronic structures remarkably, and even directly participates in catalytic reactions. Here we report that Pd nanoparticles (NPs) supported on oxygen-functionalized carbon black (Pd/O-C) show an unexpected inverse trend of selectivity on Pd particle size in chemoselective hydrogenation of para-chloronitrobenzene (p-CNB), compared to those on carbon black (Pd/C). In situ X-ray photoemission spectroscopy reveals that the Pd NPs are more positively charged with decrease of particle size in both samples, while the Pd NPs in Pd/O-C have relatively higher fractions of positive Pdδ+ species than those in Pd/C with similar sizes. Fourier transform infrared spectroscopy shows that the balance of positive Pdδ+ species strongly modulates the competitive adsorption of -NO2 and -Cl group in p-CNB according to their different electronegativities. As a consequence, we, for the first time, demonstrate that a moderate positive charge of Pd NPs is essential to improve the p-chloroaniline (p-CAN) selectivity, while too high or too low positive charge could impel the adsorption of the less negatively charged -Cl group, thus generating the dehalogenated aniline by-product. These findings suggest that precise tailoring of the electronic structures of metal NPs could be essential for design of high chemoselective metal catalysts.

Zinc-air batteries using gels as carriers for electrolyte absorption have attracted extensive attention due to their flexibility, deformability, and high specific capacity. However, traditional mono-polymer gel electrolytes display poor mechanical properties and low ionic conductivity at wide-window temperatures. Here, the enhanced gel polymer (PAM-F/G) modified by dual surfactants is present by way of pluronic F127 and layered graphene oxide introduced into the polyacrylamide (PAM) matrix. The gel electrolyte procured by absorbing 6 M KOH exhibits improved mechanical characteristics, temperature adaptability, and a satisfactory ionic conductivity (276 mS cm

The entry of collective-owned commercial construction land into the market is a major reform of China’s land management system, which will help promote the appreciation of rural land, establish a unified urban and rural construction land market, and help rural revitalisation and urban–rural integrated development. Based on the classic customer satisfaction index model, this study constructs a satisfaction model for farmers who enter the market with collective-owned commercial construction land. Farmers’ satisfaction is measured by 7 latent variables and the corresponding 22 observed variables, forming a causal chain containing 13 pairs of interactions. Taking as an example Dazu District of Chongqing City, one of the pilot areas where China’s collective-owned commercial construction land has come on the market, AMOS statistical analysis software is used to test the hypotheses. The research results show that: farmers’ information awareness has the greatest impact on farmers’ satisfaction; the higher farmers’ perceived quality is, the more they can improve their satisfaction; there is a significant relationship between farmers’ satisfaction, farmers’ complaints and farmers’ trust; and the three are closely related. Finally, based on the research results, we try to put forward targeted policy suggestions in order to provide a useful reference for government to push for the promotion of the collective-owned commercial construction land marketisation in other rural areas of China and its future improvement.

Coastal saltmarshes are key ecosystems with important ecological functions. Yet, they have experienced a widespread decline. Due to their importance, the conservation and restoration of saltmarshes are globally shared objectives, including China. Despite multiple local studies, nationwide information about saltmarshes in China is scarce. Thus, we used remote sensing to delineate the spatial distribution and areal extent of saltmarshes along coastal China and resolve their species composition. By interpreting 10 m spatial resolution Sentinel-2 images on Google Earth Engine, assisted with field survey and literature search, a total of 118 010 ha of saltmarshes were delineated in coastal China in 2019. Seven typical saltmarsh species were identified, with Phragmites australis, Spartina alterniflora, and Scirpus mariquater as dominant species, accounting for 95.5% of total saltmarsh extent, while Suaeda salsa, Tamarix chinensis, Cyperus malaccensis, and Sesuvium portulacastrum were present in limited abundance. The P. australis and exotic species S. alterniflora grow along almost all coastal provinces, but P. australis dominates in the north while S. alterniflora dominates in the middle part of coastal China. Suaeda salsa occurs mainly in the north and has suffered large losses. Tamarix chinensis is abundant in Shandong province, S. mariquater in the Yangtze River delta, C. malaccensis in Guangdong and Guangxi provinces, and S. portulacastrum in Taiwan. The exotic species S. alterniflora expanded extensively along the coast and its expansion rate continues to increase. The results provided conform a much-needed baseline for future monitoring efforts and the assessment of progress in the conservation and restoration projects toward recovering saltmarshes in China.

Strong metal–support interaction (SMSI) has long been studied in catalytic reactions. Proper utilization of the SMSI effect might not only improve the stability of the catalysts, but also the activity and selectivity. In this work, using the atomic layer deposition (ALD) technique, we synthesized a series of Pd/ZnO catalysts with Pd particle sizes ranging from 1.6 to 7.9 nm. Upon H2 reduction at elevated temperatures, these Pd/ZnO catalysts display a size-dependent SMSI effect wherein the larger-size Pd particles are more prone to be encapsulated by ZnO compared to the smaller ones. In the reaction of CO2 hydrogenation, we show that such size-dependent SMSI, together with the size-related CO binding strength on Pd particles, provides a higher activity and methanol selectivity to the Pd particles larger than ~2.5 nm.

Trichoderma harzianum EU2-77 was a mutant strain of the wild-type strain T. harzianum NP13a isolated in Singapore. A multi-mutagenesis one-screening (MMOS) method was developed to further improve strain EU2-77 and a new mutant EUA20 was obtained. It exhibited filter paper cellulase (FPase) activity up to 14.79 IU/mL within 6 days shake flask cultivation. Activities of FPase, endoglucanase, β-glucosidase, and xylanase, and protein content by EUA20 were respectively increased to 5.73, 4.35, 7.34, 1.80 and 2.70 folds. Using pretreated oil palm empty fruit bunch (OPEFB) and corncob powder as the substrates, strain EUA20 presented approximate 6.52 and 8.80 IU/ml FPase activity. Reducing sugar yield of 615.8 and 636.8 mg/g biomass were respectively obtained for OPEFB and corncob powder using cellulolytic enzymes of strain EUA20. Our results demonstrated that mutant strain EUA20 had great potential in on-site cellulase production for effective biomass bioconversion.

Salt blocking and low evaporation efficiency under weak sun irradiation are two obstacles of solar-thermal seawater desalination in the industrialization process. Herein, the challenges are overcome by a solar-thermal interfacial membrane evaporation (STIME) system, i.e., combining merits of advanced thermal management of interfacial evaporation and salt insulation of membrane evaporation, simultaneously achieving salt-resistance, hydrovoltaic generation, and all-weather vapor generation. By employing a hybrid system based on sandwich -like MXene-graphene oxide-MXene (MGM) on a commercial PVDF membrane (MGM@PVDF), we achieved an evaporation efficiency up to 92.5% and without any salt accumulation for 10 h at 10 wt% NaCl solution. Moreover, the system can also be driven by Joule-heating effect for water evaporation under dark or cloudy conditions The maximum evaporation rate of this system driven by sunlight (0.5 sun) and electricity (36 V) can reach 10.5 kg m -2h- 1. Apart from water evaporation, the MGM@PVDF modules possess excellent molecular sieve effect and can pretreat dye pollution before desalination. Furthermore, the MGM@PVDF also exhibits excellent anti-bacterial effect and biocompatibility, ensuring ecological balance during real-world applications. Thus, the developed STIME system provides a novel avenue for all-weather steam generation to constantly provide safe drinking water. Refereed/Peer-reviewed

Hydrogenation of nitriles represents as an atom-economic route to synthesize amines, crucial building blocks in fine chemicals. However, high redox potentials of nitriles render this approach to produce a mixture of amines, imines and low-value hydrogenolysis byproducts in general. Here we show that quasi atomic-dispersion of Pd within the outermost layer of Ni nanoparticles to form a Pd1Ni single-atom surface alloy structure maximizes the Pd utilization and breaks the strong metal-selectivity relations in benzonitrile hydrogenation, by prompting the yield of dibenzylamine drastically from ∼5 to 97% under mild conditions (80 °C; 0.6 MPa), and boosting an activity to about eight and four times higher than Pd and Pt standard catalysts, respectively. More importantly, the undesired carcinogenic toluene by-product is completely prohibited, rendering its practical applications, especially in pharmaceutical industry. Such strategy can be extended to a broad scope of nitriles with high yields of secondary amines under mild conditions. While nitrile hydrogenation may provide an appealing means to obtain secondary amines, poor selectivity plagues heterogeneous catalysts. Here, authors report single-atom palladium on nickel catalysts to afford high yields of secondary amines from a broad range of parent nitriles.

Al-air batteries are regarded as the potential energy conversion systems due to the ultra-high theoretical specific ca-pacity of 2980 mAh/g and specific energy of 8100 mWh/g for Al anodes. However, the anodic self-corrosion has severely limited the energy efficiency, which induces a great challenge to the commercial penetration of Al-air batteries. Here, we present an alkaline electrolyte optimization with a single inorganic Zn-compound, where a strong Lewis acid ZnCl2 has the best modification effect for Al-air battery compared with ZnO and ZnCO3. The results demonstrate that the inhibition efficiency of Al anode is up to 83.03% under the adsorption of strong Lewis acid groups on the Zn protective film. The high specific capacity of 2322.91 mAh/g and specific energy of 2457.02 mWh/g for Al-air battery are obtained at the galvanostatic condition of 20 mA/cm(2) , and the anode efficiency is enhanced to 77.95% after ZnCl2 optimization. Moreover, the optimization mechanism is revealed, which provides a technical basis for the application of the enhanced -performance Al-air batteries in the fields of energy conversion and power supply.

Single-atom catalysts (SACs) have recently attracted broad attention in the catalysis field due to their maximized atom efficiency and unique catalytic properties. An atomic-level understanding of the interaction between the metal atoms and support is vital for developing stable and high-performance SACs. In this work, Pt1 single atoms with loadings up to 4 wt.% were fabricated on ceria nanorods using the atomic layer deposition technique. To understand the Pt–O–Ce bond interfacial interactions, the stability of Pt1 single atoms in the hydrogen reducing environment was extensively investigated by using in situ diffuse reflectance infrared Fourier transform spectroscopy CO chemisorption measurements. It was found that ceria defect sites, metal loadings and high-temperature calcination are effective ways to tune the stability of Pt1 single atoms in the hydrogen environment. X-ray photoemission spectroscopy further showed that Pt1 single atoms on ceria are dominantly at a +2 valence state at the defect and step edge sites, while those on terrace sites are at a +4 state. The above tailored stability and electronic properties of Pt1 single atoms are found to be strongly correlated with the catalytic activity in the dry and water-mediated CO oxidation reactions.

Proton-exchange-membrane fuel cells (PEMFCs) are attractive next-generation power sources for use in vehicles and other applications1, with development efforts focusing on improving the catalyst system of the fuel cell. One problem is catalyst poisoning by impurity gases such as carbon monoxide (CO), which typically comprises about one per cent of hydrogen fuel2-4. A possible solution is on-board hydrogen purification, which involves preferential oxidation of CO in hydrogen (PROX)3-7. However, this approach is challenging8-15 because the catalyst needs to be active and selective towards CO oxidation over a broad range of low temperatures so that CO is efficiently removed (to below 50 parts per million) during continuous PEMFC operation (at about 353 kelvin) and, in the case of automotive fuel cells, during frequent cold-start periods. Here we show that atomically dispersed iron hydroxide, selectively deposited on silica-supported platinum (Pt) nanoparticles, enables complete and 100 per cent selective CO removal through the PROX reaction over the broad temperature range of 198 to 380 kelvin. We find that the mass-specific activity of this system is about 30 times higher than that of more conventional catalysts consisting of Pt on iron oxide supports. In situ X-ray absorption fine-structure measurements reveal that most of the iron hydroxide exists as Fe1(OH)x clusters anchored on the Pt nanoparticles, with density functional theory calculations indicating that Fe1(OH)x-Pt single interfacial sites can readily react with CO and facilitate oxygen activation. These findings suggest that in addition to strategies that target oxide-supported precious-metal nanoparticles or isolated metal atoms, the deposition of isolated transition-metal complexes offers new ways of designing highly active metal catalysts.

The high-dense metal-air batteries are difficult to commercialize on a large scale mainly because of sluggish kinetics of air electrode. The catalysts are of crucial importance for the rate of oxygen reduction reaction (ORR), among which Pt-based catalysts for ORR have shortcomings in stability and cost, and the kind of catalysts with adding C and N to transition metals receive more attention. Here we analyze catalytic performance of graphene supported transition metals-N4(M-N4@G) for ORR based on density functional theory (DFT), verifying rationality of such catalysts with five different transition metals (Pt, Fe, Co, Pd and Ni) embedded in the graphene, and demonstrating that Fe-N4@G has better ORR performance than Pt-N4@G. Moreover, a proposed mechanism of ORR (generating free *O and *OH) is explored to optimize ORR by means of transition-state search in the DFT calculation. Additionally, a novel phenomenon is observed that graphene has a strong attraction to hydrogen atoms, which is facilitated to promote hydrogen evolution reaction of graphene supported catalysts.

This study compared the ability of Sargassum fusiforme to accumulate As, Cd, Cr, Cu, Ni, Pb and Zn in its five tissues (main branch, lateral branch, leaf, receptacles and pneumathode). The concentrations of these trace elements in seawater, surface sediments and different tissues of S. fusiforme were analyzed in different areas in Dongtong County (Wenzhou City, China). The presence of receptacle at all sites indicated that S. fusiforme had entered the mature stage. However, the proportion of each tissue in S. fusiforme in different sites was varied, indicating subtle differences in growth. S. fusiforme has a great capacity to accumulate trace elements, showing relatively high levels of As (28.2–64.2 mg kg−1) and Zn (19.9–80.8 mg kg−1). The elements are mainly stored in leaf, receptacles and pneumathode. Compared to element concentrations in the surrounding environment, the seaweed exhibited stronger bioconcentration capacity for As and Cd than for other elements. According to our health risk assessment results, the hazard index and carcinogenic risk were below the limit, suggesting that the S. fusiforme ingestion would not pose any health risk and the potential risk of intake branches was even lower than that of other tissues.

Bifunctional catalysts that contain both metal and acidic functions have been widely used in renewable biomass conversions. The bifunctionality closely depends on the distance between the metal and acid sites. However, the metal–acid proximity effect has rarely investigated in biomass conversions. In this work, we precisely deposited a porous Al2O3 overcoat onto a Pt/Al2O3 catalyst using atomic layer deposition to improve the proximity between the Pt metal and the alumina acid sites by increasing the area of the metal–acid interface. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of pyridine chemisorption confirmed that the overall catalyst acidity did not change considerably after applying the alumina overcoat. In the aqueous-phase, hydrogenolysis of glycerol was used to demonstrate that the alumina overcoat significantly improved the activity approximately 2.8-fold, as well as the selectivity to 1,2-propanediol (1,2-PD) at high conversions. DRIFTS measurements of CO chemisorption indicated that the Pt-alumina interface had greater area for alumina coated Pt/Al2O3 than for the uncoated analog. Moreover, we used the hydrogenation of acetol, the key reaction intermediate in glycerol hydrogenolysis, as a control experiment to confirm that the observed activity improvement in the hydrogenolysis of glycerol could be attributed to the enhancement of the dehydration reaction step, which requires acidic function. In brief, our work provides solid evidence that close metal–acid proximity enhances bifunctionality, thus improving the catalytic activity.