Machine Learning Big Data Set Analysis Reveals C-C Electro-Coupling Mechanism.

Carbon-carbon (C-C) coupling is essential in the electrocatalytic reduction of CO2 for the production of green chemicals. However, due to the complexity of the reaction network, there remains controversy regarding the underlying reaction mechanisms and the optimal direction for catalyst material design. Here, we present a global perspective to establish a comprehensive data set encompassing all C-C coupling precursors and catalytic active site compositions to explore the reaction mechanisms and screen catalysts via big data set analysis. The 2D-3D ensemble machine learning strategy, developed to target a variety of adsorption configurations, can quickly and accurately expand quantum chemical calculation data, enabling the rapid acquisition of this extensive big data set. Analyses of the big data set establish that (1) asymmetric coupling mechanisms exhibit greater potential efficiency compared to symmetric coupling, with the optimal path involving the coupling CHO with CH or CH2, and (2) C-C coupling selectivity of Cu-based catalysts can be enhanced through bimetallic doping including CuAgNb sites. Importantly, we experimentally substantiate the CuAgNb catalyst to demonstrate actual boosted performance in C-C coupling. Our finding evidence the practicality of our big data set generated from machine learning-accelerated quantum chemical computations. We conclude that combining big data with complex catalytic reaction mechanisms and catalyst compositions will set a new paradigm for accelerating optimal catalyst design.

Protein Interfacial Gelation toward Shuttle-Free and Dendrite-Free Zn-Iodine Batteries.

Aqueous zinc-iodine (Zn-I2) batteries hold potential for large-scale energy storage but struggle with shuttle effects of I2 cathodes and poor reversibility of Zn anodes. Here, an interfacial gelation strategy is proposed to suppress the shuttle effects and improve the Zn reversibility simultaneously by introducing silk protein (SP) additive. The SP can migrate bidirectionally toward cathode and anode interfaces driven by the periodically switched electric field direction during charging/discharging. For I2 cathodes, the interaction between SP and polyiodides forms gelatinous precipitate to avoid the polyiodide dissolution, evidenced by excellent electrochemical performance, including high specific capacity and Coulombic efficiency (CE) (215 mAh g-1 and 99.5% at 1 C), excellent rate performance (≈170 mAh g-1 at 50 C), and extended durability (6000 cycles at 10 C). For Zn anodes, gelatinous SP serves as protective layer to boost the Zn reversibility (99.7% average CE at 2 mA cm-2) and suppress dendrites. Consequently, a 500 mAh Zn-I2 pouch cell with high-loading cathode (37.5 mgiodine cm-2) and high-utilization Zn anode (20%) achieves remarkable energy density (80 Wh kg-1) and long-term durability (>1000 cycles). These findings underscore the simultaneous modulation of both cathode and anode and demonstrate the potential for practical applications of Zn-I2 batteries.

Developing Cathode Films for Practical All-Solid-State Lithium-Sulfur Batteries.

The development of all-solid-state lithium-sulfur batteries (ASSLSBs) toward large-scale electrochemical energy storage is driven by the higher specific energies and lower cost in comparison with the state-of-the-art Li-ion batteries. Yet, insufficient mechanistic understanding and quantitative parameters of the key components in sulfur-based cathode hinders the advancement of the ASSLSB technologies. This review offers a comprehensive analysis of electrode parameters, including specific capacity, voltage, S mass loading and S content toward establishing the specific energy (Wh kg-1) and energy density (Wh L-1) of the ASSLSBs. Additionally, this work critically evaluates the progress in enhancing lithium ion and electron percolation and mitigating electrochemical-mechanical degradation in sulfur-based cathodes. Last, a critical outlook on potential future research directions is provided to guide the rational design of high-performance sulfur-based cathodes toward practical ASSLSBs.

The role of electrocatalytic materials for developing post-lithium metal||sulfur batteries.

The exploration of post-Lithium (Li) metals, such as Sodium (Na), Potassium (K), Magnesium (Mg), Calcium (Ca), Aluminum (Al), and Zinc (Zn), for electrochemical energy storage has been driven by the limited availability of Li and the higher theoretical specific energies compared to the state-of-the-art Li-ion batteries. Post-Li metal||S batteries have emerged as a promising system for practical applications. Yet, the insufficient understanding of quantitative cell parameters and the mechanisms of sulfur electrocatalytic conversion hinder the advancement of these battery technologies. This perspective offers a comprehensive analysis of electrode parameters, including S mass loading, S content, electrolyte/S ratio, and negative/positive electrode capacity ratio, in establishing the specific energy (Wh kg-1) of post-Li metal||S batteries. Additionally, we critically evaluate the progress in investigating electrochemical sulfur conversion via homogeneous and heterogeneous electrocatalytic approaches in both non-aqueous Na/K/Mg/Ca/Al||S and aqueous Zn||S batteries. Lastly, we provide a critical outlook on potential research directions for designing practical post-Li metal||S batteries.

Aqueous Zinc-Iodine Pouch Cells with Long Cycling Life and Low Self-Discharge.

Aqueous zinc batteries are practically promising for large-scale energy storage because of cost-effectiveness and safety. However, application is limited because of an absence of economical electrolytes to stabilize both the cathode and anode. Here, we report a facile method for advanced zinc-iodine batteries via addition of a trace imidazolium-based additive to a cost-effective zinc sulfate electrolyte, which bonds with polyiodides to boost anti-self-discharge performance and cycling stability. Additive aggregation at the cathode improves the rate capacity by boosting the I2 conversion kinetics. Also, the introduced additive enhances the reversibility of the zinc anode by adjusting Zn2+ deposition. The zinc-iodine pouch cell, therefore, exhibits industrial-level performance evidenced by a ∼99.98% Coulombic efficiency under ca. 0.4C, a significantly low self-discharge rate with 11.7% capacity loss per month, a long lifespan with 88.3% of initial capacity after 5000 cycles at a 68.3% zinc depth-of-discharge, and fast-charging of ca. 6.7C at a high active-mass loading >15 mg cm-2. Highly significant is that this self-discharge surpasses commercial nickel-metal hydride batteries and is comparable with commercial lead-acid batteries, together with the fact that the lifespan is over 10 times greater than reported works, and the fast-charging performance is better than commercial lithium-ion batteries.

Impact of surface chemical treatment in surgical regenerative treatment of ligature-induced peri-implantitis: A canine study.

BACKGROUND: Implant surface decontamination is a critical step in peri-implantitis treatment. The aim of this study was to assess the effect chemotherapeutic agents have on reosseointegration after treatment on ligature-inducted peri-implantitis. METHODS: Six male canines had 36 implants placed and ligatures were placed around them for 28 weeks to establish peri-implantitis. The peri-implant defects were randomly treated by 1 of 3 methods: 0.12% chlorhexidine (CHX test group), 1.5% sodium hypochlorite (NaOCl test group), or saline (Control group). Sites treated with NaOCl and CHX were grafted with autogenous bone, and all sites then either received a collagen membrane or not. Histology sections were obtained at 6 months postsurgery to assess percentage of reosseointegration. RESULTS: Thirty-five implants were analyzed (CHX: 13; NaOCl: 14; Control:8). NaOCl-treated sites demonstrated reosseointegration with direct bone-to-implant-contact on the previously contaminated surfaces (42% mean reosseointegration), which was significantly higher than Controls (p < 0.05). Correspondingly, clinical improvement was noted with a significant reduction in probing depth from 5.50 ± 1.24 mm at baseline to 4.46 ± 1.70 mm at 6-months postsurgery (p = 0.006). CHX-treated sites demonstrated a nonsignificant reosseointegration of 26% (p > 0.05); however, in the majority of cases, the new bone growth was at a distance from the implant surface without contact. Probing depths did not improve in the CHX group. The use of membrane did not influence reosseointegration or probing depths (all p > 0.05). CONCLUSION: Titanium implants with peri-implantitis have the capacity to reosseointegrate following regenerative surgery. However, treatment response is contingent upon the chemotherapeutic agent selection. Additional chemical treatment with 1.5% NaOCl lead to the most favorable results in terms of changes in defect depth and percentage of reosseointegration as compared to CHX, which may hinder reosseointegration.

Impacts of forest age on soil characteristics and fertility quality of Populus simonii shelter forest at the southern edge of the Horqin Sandy Land, China.

The sand fixing shelter forests in the Horqin Sandy Land are a key area in the "3-North" Shelter Forest Program in China, which has a history of over 50 years of artificial afforestation. Populus simonii Carr is one of the most dominant silvicultural species in the region. The aim of this study is to understand the soil characteristics and soil fertility of Populus simonii shelter forests at different growth stages and to establish a scientific basis for soil nutrient regulation and sustainable management of Populus simonii shelter forests at the southern edge of the Horqin Sandy Land. Sample plots were selected for young (≤15 a), middle-aged (16-25 a), near-mature (26-30 a), mature (31-40 a), and over-mature (≥41 a) forests. Each forest studied was in a state of natural restoration with uniform stand conditions and no artificial fertilizer was applied. These sites were selected to study changes in the soil characteristics in soil depths of 0-20, 20-40, and 40-60 cm. In order to avoid the problem of multicollinearity between soil variables and to reduce redundancy, principal component analysis (PCA), Pearson's correlation analysis, and Norm value calculation were used to select the least correlated indicators with the highest factor loadings. This was used to establish the minimum data set. The soil fertility quality of these shelterbelts in different forest ages was quantified using the soil quality index (SQI). In the growth stage from young to nearly mature forests, the soil bulk weight and pH decreased with increasing forest age. Soil capillary porosity, noncapillary porosity, total porosity, water content, field water holding capacity, and organic carbon content increased with increasing forest age and soil nutrient content gradually improved. At the stage of near-mature to over-mature forests, the effect of forest age on soil bulk density was not significant and all other soil characteristics decreased to varying degrees as the forest age increased. The soil also developed from alkaline to neutral. The SQI of the total data set and the SQI of the minimum data set consistently showed that near-mature forests (NMF) > middle-aged forests (MAF) > mature forests (MF) > over-mature forests (OMF) > young forests (YF). The results of the two evaluation systems showed a significant positive correlation (P < 0.05, R 2 = 0.8263) indicating that it is feasible to use the minimum data set to evaluate the soil fertility of shelter forests of different forest ages. The age of the forest has an obvious effect on the soil characteristics and overall soil fertility of shelter forests. The Populus simonii shelter forests on the southern edge of the Horqin Sandy Land have great soil development at the early stage of afforestation and the soil nutrient content gradually increases. The soil fertility reaches a peak when the forest is nearly mature and the soil fertility declines after the age of the forest reaches 30 years.

Electrocatalytic Acetylene Hydrogenation in Concentrated Seawater at Industrial Current Densities.

Electrocatalytic acetylene hydrogenation to ethylene (E-AHE) is a promising alternative for thermal-catalytic process, yet it suffers from low current densities and efficiency. Here, we achieved a 71.2 % Faradaic efficiency (FE) of E-AHE at a large partial current density of 1.0 A cm-2 using concentrated seawater as an electrolyte, which can be recycled from the brine waste (0.96 M NaCl) of alkaline seawater electrolysis (ASE). Mechanistic studies unveiled that cation of concentrated seawater dynamically prompted unsaturated interfacial water dissociation to provide protons for enhanced E-AHE. As a result, compared with freshwater, a twofold increase of FE of E-AHE was achieved on concentrated seawater-based electrolysis. We also demonstrated an integrated system of ASE and E-AHE for hydrogen and ethylene production, in which the obtained brine output from ASE was directly fed into E-AHE process without any further treatment for continuously cyclic operations. This innovative system delivered outstanding FE and selectivity of ethylene surpassed 97.0 % and 97.5 % across wide-industrial current density range (≤ 0.6 A cm-2), respectively. This work provides a significant advance of electrocatalytic ethylene production coupling with brine refining of seawater electrolysis.

Advanced cathodes for aqueous Zn batteries beyond Zn2+ intercalation.

Aqueous zinc (Zn) batteries have attracted global attention for energy storage. Despite significant progress in advancing Zn anode materials, there has been little progress in cathodes. The predominant cathodes working with Zn2+/H+ intercalation, however, exhibit drawbacks, including a high Zn2+ diffusion energy barrier, pH fluctuation(s) and limited reproducibility. Beyond Zn2+ intercalation, alternative working principles have been reported that broaden cathode options, including conversion, hybrid, anion insertion and deposition/dissolution. In this review, we report a critical assessment of non-intercalation-type cathode materials in aqueous Zn batteries, and identify strengths and weaknesses of these cathodes in small-scale batteries, together with current strategies to boost material performance. We assess the technical gap(s) in transitioning these cathodes from laboratory-scale research to industrial-scale battery applications. We conclude that S, I2 and Br2 electrodes exhibit practically promising commercial prospects, and future research is directed to optimizing cathodes. Findings will be useful for researchers and manufacturers in advancing cathodes for aqueous Zn batteries beyond Zn2+ intercalation.

Accuracy of robotic surgery for dental implant placement: A systematic review and meta-analysis.

OBJECTIVES: To systematically analyze the accuracy of robotic surgery for dental implant placement. MATERIALS AND METHODS: PubMed, Embase, and Cochrane CENTRAL were searched on October 25, 2023. Model studies or clinical studies reporting the accuracy of robotic surgery for dental implant placement among patients with missing or hopeless teeth were included. Risks of bias in clinical studies were assessed. Meta-analyses were undertaken. RESULTS: Data from 8 clinical studies reporting on 109 patients and 242 implants and 13 preclinical studies were included. Positional accuracy was measured by comparing the implant plan in presurgery CBCT and the actual implant position in postsurgery CBCT. For clinical studies, the pooled (95% confidence interval) platform deviation, apex deviation, and angular deviation were 0.68 (0.57, 0.79) mm, 0.67 (0.58, 0.75) mm, and 1.69 (1.25, 2.12)°, respectively. There was no statistically significant difference between the accuracy of implants placed in partially or fully edentulous patients. For model studies, the pooled platform deviation, apex deviation, and angular deviation were 0.72 (0.58, 0.86) mm, 0.90 (0.74, 1.06) mm, and 1.46 (1.22, 1.70)°, respectively. No adverse event was reported. CONCLUSION: Within the limitation of the present systematic review, robotic surgery for dental implant placement showed suitable implant positional accuracy and had no reported obvious harm. Both robotic systems and clinical studies on robotic surgery for dental implant placement should be further developed.

All-dielectric absorber based on nano-graphite sheets/ionogels with configurable absorbing band.

With the increasing complexity of the electromagnetic environment, there is a growing demand for the manipulation of electromagnetic waves, leading to the rapid development in configurable microwave absorbers. All-dielectric absorbers offer broadband and high-intensity absorption effects in microwave absorption and shielding. However, they face a significant challenge: their performance is not adjustable once the design is completed. In this study, we propose a solution to this problem by creating all-dielectric absorbers with flexibly configurable absorbing properties. We achieve this by designing a composite material of ionogels/nano-graphite sheets into compressible deformable absorbing units that can be molded into different shapes using 3D printing modes. The plasticity allows us to change the performance of the all-dielectric absorber, including the microwave absorption intensity, absorption peak, frequency bandwidths, and wide-angle absorption performance. With this approach, we can flexibly manipulate electromagnetic waves using all-dielectric absorbers through different plasticity models.

Recent advancement on photocatalytic plastic upcycling.

More than 8 billion tons of plastics have been generated since 1950. About 80% of these plastics have been dumped in landfills or went into natural environments, resulting in ever-worsening contamination. Among various strategies for waste plastics processing (e.g., incineration, mechanical recycling, thermochemical conversion and electrocatalytic/photocatalytic techniques), photocatalysis stands out as a cost-effective, environmentally benign and clean technique to upcycle plastic waste at ambient temperature and pressure using solar light. The mild reaction conditions for photocatalysis enable the highly selective conversion of plastic waste into targeted value-added chemicals/fuels. Here, we for the first time summarize the recent development of photocatalytic plastic upcycling based on the chemical composition of photocatalysts (e.g., metal oxides, metal sulfides, non-metals and composites). The pros and cons of various photocatalysts have been critically discussed and summarized. At last, the future challenges and opportunities in this area are presented in this review.

Developing high-power Li||S batteries via transition metal/carbon nanocomposite electrocatalyst engineering.

The activity of electrocatalysts for the sulfur reduction reaction (SRR) can be represented using volcano plots, which describe specific thermodynamic trends. However, a kinetic trend that describes the SRR at high current rates is not yet available, limiting our understanding of kinetics variations and hindering the development of high-power Li||S batteries. Here, using Le Chatelier's principle as a guideline, we establish an SRR kinetic trend that correlates polysulfide concentrations with kinetic currents. Synchrotron X-ray adsorption spectroscopy measurements and molecular orbital computations reveal the role of orbital occupancy in transition metal-based catalysts in determining polysulfide concentrations and thus SRR kinetic predictions. Using the kinetic trend, we design a nanocomposite electrocatalyst that comprises a carbon material and CoZn clusters. When the electrocatalyst is used in a sulfur-based positive electrode (5 mg cm-2 of S loading), the corresponding Li||S coin cell (with an electrolyte:S mass ratio of 4.8) can be cycled for 1,000 cycles at 8 C (that is, 13.4 A gS-1, based on the mass of sulfur) and 25 °C. This cell demonstrates a discharge capacity retention of about 75% (final discharge capacity of 500 mAh gS-1) corresponding to an initial specific power of 26,120 W kgS-1 and specific energy of 1,306 Wh kgS-1.

Local reaction environment in electrocatalysis.

Beyond conventional electrocatalyst engineering, recent studies have unveiled the effectiveness of manipulating the local reaction environment in enhancing the performance of electrocatalytic reactions. The general principles and strategies of local environmental engineering for different electrocatalytic processes have been extensively investigated. This review provides a critical appraisal of the recent advancements in local reaction environment engineering, aiming to comprehensively assess this emerging field. It presents the interactions among surface structure, ions distribution and local electric field in relation to the local reaction environment. Useful protocols such as the interfacial reactant concentration, mass transport rate, adsorption/desorption behaviors, and binding energy are in-depth discussed toward modifying the local reaction environment. Meanwhile, electrode physical structures and reaction cell configurations are viable optimization methods in engineering local reaction environments. In combination with operando investigation techniques, we conclude that rational modifications of the local reaction environment can significantly enhance various electrocatalytic processes by optimizing the thermodynamic and kinetic properties of the reaction interface. We also outline future research directions to attain a comprehensive understanding and effective modulation of the local reaction environment.

Alkaline-based aqueous sodium-ion batteries for large-scale energy storage.

Aqueous sodium-ion batteries are practically promising for large-scale energy storage, however energy density and lifespan are limited by water decomposition. Current methods to boost water stability include, expensive fluorine-containing salts to create a solid electrolyte interface and addition of potentially-flammable co-solvents to the electrolyte to reduce water activity. However, these methods significantly increase costs and safety risks. Shifting electrolytes from near neutrality to alkalinity can suppress hydrogen evolution while also initiating oxygen evolution and cathode dissolution. Here, we present an alkaline-type aqueous sodium-ion batteries with Mn-based Prussian blue analogue cathode that exhibits a lifespan of 13,000 cycles at 10 C and high energy density of 88.9 Wh kg-1 at 0.5 C. This is achieved by building a nickel/carbon layer to induce a H3O+-rich local environment near the cathode surface, thereby suppressing oxygen evolution. Concurrently Ni atoms are in-situ embedded into the cathode to boost the durability of batteries.

Establishing Exceptional Durability in Ultralow-Temperature Organic-Sodium Batteries via Stabilized Multiphase Conversions.

Operation of rechargeable batteries at ultralow temperature is a significant practical problem because of poor kinetics of the electrode. Here, we report for the first time stabilized multiphase conversions for fast kinetics and long-term durability in ultralow-temperature, organic-sodium batteries. We establish that disodium rhodizonate organic electrode in conjunction with single-layer graphene oxide obviates consumption of organic radical intermediates, and demonstrate as a result that the newly designed organic electrode exhibits excellent electrochemical performance of a highly significant capacity of 130 mAh g-1 at -50 °C. We evidence that the full-cell configuration coupled with Prussian blue analogues exhibits exceptional cycling stability of >7000 cycles at -40 °C while maintaining a discharge capacity of 101 mAh g-1 at a high current density 300 mA g-1. We show this is among the best reported ultralow-temperature performance for nonaqueous batteries, and importantly, the pouch cell exhibits a continuous power supply despite conditions of -50 °C. This work sheds light on the distinct energy storage characteristics of organic electrode and opens up new avenues for the development of reliable and sustainable ultralow-temperature batteries.

Urea catalytic oxidation for energy and environmental applications.

Urea is one of the most essential reactive nitrogen species in the nitrogen cycle and plays an indispensable role in the water-energy-food nexus. However, untreated urea or urine wastewater causes severe environmental pollution and threatens human health. Electrocatalytic and photo(electro)catalytic urea oxidation technologies under mild conditions have become promising methods for energy recovery and environmental remediation. An in-depth understanding of the reaction mechanisms of the urea oxidation reaction (UOR) is important to design efficient electrocatalysts/photo(electro)catalysts for these technologies. This review provides a critical appraisal of the recent advances in the UOR by means of both electrocatalysis and photo(electro)catalysis, aiming to comprehensively assess this emerging field from fundamentals and materials, to practical applications. The emphasis of this review is on the design and development strategies for electrocatalysts/photo(electro)catalysts based on reaction pathways. Meanwhile, the UOR in natural urine is discussed, focusing on the influence of impurity ions. A particular emphasis is placed on the application of the UOR in energy and environmental fields, such as hydrogen production by urea electrolysis, urea fuel cells, and urea/urine wastewater remediation. Finally, future directions, prospects, and remaining challenges are discussed for this emerging research field. This critical review significantly increases the understanding of current progress in urea conversion and the development of a sustainable nitrogen economy.

Recent Advances in Electrocatalytic Hydrogenation Reactions on Copper-Based Catalysts.

Hydrogenation reactions play a critical role in the synthesis of value-added products within the chemical industry. Electrocatalytic hydrogenation (ECH) using water as the hydrogen source has emerged as an alternative to conventional thermocatalytic processes for sustainable and decentralized chemical synthesis under mild conditions. Among the various ECH catalysts, copper-based (Cu-based) nanomaterials are promising candidates due to their earth-abundance, unique electronic structure, versatility, and high activity/selectivity. Herein, recent advances in the application of Cu-based catalysts in ECH reactions for the upgrading of valuable chemicals are systematically analyzed. The unique properties of Cu-based catalysts in ECH are initially introduced, followed by design strategies to enhance their activity and selectivity. Then, typical ECH reactions on Cu-based catalysts are presented in detail, including carbon dioxide reduction for multicarbon generation, alkyne-to-alkene conversion, selective aldehyde conversion, ammonia production from nitrogen-containing substances, and amine production from organic nitrogen compounds. In these catalysts, the role of catalyst composition and nanostructures toward different products is focused. The co-hydrogenation of two substrates (e.g., CO2 and NOx n, SO3 2-, etc.) via C─N, C─S, and C─C cross-coupling reactions are also highlighted. Finally, the critical issues and future perspectives of Cu-catalyzed ECH are proposed to accelerate the rational development of next-generation catalysts.

High-Reversibility Sulfur Anode for Advanced Aqueous Battery.

Despite being extensively explored as cathodes in batteries, sulfur (S) can function as a low-potential anode by changing charge carriers in electrolytes. Here, a highly reversible S anode that fully converts from S8 0 to S2- in static aqueous S-I2 batteries by using Na+ as the charge carrier is reported. This S anode exhibits a low potential of -0.5 V (vs standard hydrogen electrode) and a near-to-theoretical capacity of 1404 mA h g-1 . Importantly, it shows significant advantages over the widely used Zn anode in aqueous media by obviating dendrite formation and H2 evolution. To suppress "shuttle effects" faced by both S and I2 electrodes, a scalable sulfonated polysulfone (SPSF) membrane is proposed, which is superior to commercial Nafion in cost (US$1.82 m-2  vs $3500 m-2 ) and environmental benignity. Because of its ultra-high selectivity in blocking polysulfides/iodides, the battery with SPSF displays excellent cycling stability. Even under 100% depth of discharge, the battery demonstrates high capacity retention of 87.6% over 500 cycles, outperforming Zn-I2 batteries with 3.1% capacity under the same conditions. These findings broaden anode options beyond metals for high-energy, low-cost, and fast-chargeable batteries.