Constructing Multi-Electron Reactions by Doping Mn2+ to Increase Capacity and Stability in K3.2V2.8Mn0.2(PO4)4/C of Phosphate Cathodes for Potassium-Ion Batteries.

Vanadium-based phosphate cathode materials (e.g., K3V2(PO4)3) have attracted widespread concentration in cathode materials in potassium-ion batteries owing to their stable structure but suffer from low capacity and poor conductivity. In this work, an element doping strategy is applied to promote its electrochemical performance so that K3.2V2.8Mn0.2(PO4)4/C is prepared via a simple sol-gel method. The heterovalent Mn2+ is introduced to stimulated multiple electron reactions to improve conductivity and capacity, as well as interlayer spacing. Galvanostatic intermittent titration technique (GITT) and in situ X-ray diffraction results further confirm that Mn-doping in the original electrode can obtain superior electrode process kinetics and structural stability. The prepared K3.2V2.8Mn0.2(PO4)4/C exhibits a high-capacity retention of 80.8% after 1 500 cycles at 2 C and an impressive rate capability, with discharge capacities of 87.6 at 0.2 C and 45.4 mA h g-1 at 5 C, which is superior to the majority of reported vanadium-based phosphate cathode materials. When coupled K3.2V2.8Mn0.2(PO4)4/C cathode with commercial porous carbon (PC) anode as the full cell, a prominent energy density of 175 Wh kg-1 is achieved based on the total active mass. Overall, this study provides an effective strategy for meliorating the cycling stability and capacity of the polyanion cathodes for KIB.

Recent Advances of Transition Metal Dichalcogenides-Based Materials for Energy Storage Devices, in View of Monovalent to Divalent Ions.

The fast growth of electrochemical energy storage (EES) systems necessitates using innovative, high-performance electrode materials. Among the various EES devices, rechargeable batteries (RBs) with potential features like high energy density and extensive lifetime are well suited to meet rapidly increasing energy demands. Layered transition metal dichalcogenides (TMDs), typical two dimensional (2D) nanomaterial, are considered auspicious materials for RBs because of their layered structures and large specific surface areas (SSA) that benefit quick ion transportation. This review summarizes and highlights recent advances in TMDs with improved performance for various RBs. Through novel engineering and functionalization used for high-performance RBs, we briefly discuss the properties, characterizations, and electrochemistry phenomena of TMDs. We summarised that engineering with multiple techniques, like nanocomposites used for TMDs receives special attention. In conclusion, the recent issues and promising upcoming research openings for developing TMDs-based electrodes for RBs are discussed.

A study of the factors which influence digital transformation in Kibs companies.

Eighteen interviews were used in this research to inductively conceptualize the factors that influence digital transformation (DT) in Kibs companies that provide multidisciplinary Knowledge Intensive Business Services. Two main groups were identified: factors of DT and use in the new digital environment. Using the findings obtained, a comparison was made with the existing literature and the most relevant aspects of DT as a disruptive phenomenon which can generate intra-organizational competitive advantage are exposed. Objective: To identify the factors of innovation-oriented organizational management, generated by the collaboration of the professional grouping of Kibs companies through the systematization of knowledge, which serve to conceptually delimit the DT phenomenon. Ultimately, it is expected to establish recommendations for this type of companies based on providing services with high knowledge value that strive to digitally transform their businesses. Originality: the paper contributes to advancing the conceptual understanding of DT through the study of Kibs companies, which remain understudied. Likewise, there is no known study that analyzes the factors that give rise to DT in a professional grouping of small Kibs companies. It is clear that this union of small companies generates a strong internal capacity for knowledge absorption, through daily interactions with clients and public administrations, which favors the process of implementing certain technological and strategic components that are beneficial for the development of professional activity and increases the propensity to innovate. Methodology: qualitative content was analysed using a grounded theory methodology including interviews with experts and the managers of the Kibs companies in the professional sector to obtain a solid basis that can be used to identify the most relevant factors of DT. Findings/results: as DT is a multidimensional phenomenon of individual companies, this study presents a conceptual framework for the term with the strategic requirements of the market, organizations, public institutions and technological infrastructures of the professional sector. By considering the disruptive factors of digital development in this macroenvironment, conclusions can be made about the basic principles and effects of DT.

Understanding the Joint Impacts of Cognitive, Social, and Geographic Proximities on the Performance of Innovation Collaboration Between Knowledge-Intensive Business Services and the Manufacturing Industry: Empirical Evidence From China.

Most previous empirical studies just addressed the influence of geographical proximity on interactive learning regarding the collaboration between knowledge-intensive business service (KIBS) and manufacturing industries. Drawing upon the social cognitive and knowledge-based perspective, this study bridged the research gaps by investigating the joint effects of geographical proximity and two representative non-geographic-proximities (i.e., cognitive proximity and social proximity) in fostering manufacturing firms' innovation performance. In terms of the empirical analysis, we applied a research sample that involves the data of various manufacturing industries in 260 cities of China from 2003 to 2014 to test the corresponding hypotheses. Additionally, the Spatial Durbin Model (SDM) was adopted and the research findings showed that: (i) the geographic and social proximity significantly promote the knowledge transfer from KIBS to manufacturing firms, which further improves the innovation performance of the latter. However, the effect of cognitive proximity presents insignificant; (ii) the interactive effect of geographic and social proximity was positively associated with the innovation collaboration between KIBS and manufacturing firms; (iii) although the individual effect of cognitive proximity was insignificant, when it interacted with geographic or social proximity, the joint effects were proved to promote the innovation performance of manufacturing firms. This study extends our understanding pertaining to the influencing mechanism of proximity for KIBS and the innovation process. The findings proved that geographic and social proximity are two imperative facilitators of knowledge-creating collaboration, highlighting their indispensable role in moderating and mediating the knowledge transfer of KIBS as well as the innovation performance of manufacturing firms. Notably, cognitive proximity is contingent upon geographic and social proximity on its positive effects on the innovation performance for KIBS and their clients' collaboration.

Dendrite-Free Potassium Metal Anodes in a Carbonate Electrolyte.

Potassium (K) metal anodes suffer from a challenging problem of dendrite growth. Here, it is demonstrated that a tailored current collector will stabilize the metal plating-stripping behavior even with a conventional KPF6 -carbonate electrolyte. A 3D copper current collector is functionalized with partially reduced graphene oxide to create a potassiophilic surface, the electrode being denoted as rGO@3D-Cu. Potassiophilic versus potassiophobic experiments demonstrate that molten K fully wets rGO@3D-Cu after 6 s, but does not wet unfunctionalized 3D-Cu. Electrochemically, a unique synergy is achieved that is driven by interfacial tension and geometry: the adherent rGO underlayer promotes 2D layer-by-layer (Frank-van der Merwe) metal film growth at early stages of plating, while the tortuous 3D-Cu electrode reduces the current density and geometrically frustrates dendrites. The rGO@3D-Cu symmetric cells and half-cells achieve state-of-the-art plating and stripping performance. The symmetric rGO@3D-Cu cells exhibit stable cycling at 0.1-2 mA cm-2 , while baseline Cu prematurely fails when the current reaches 0.5 mA cm-2 . The half-cells cells of rGO@3D-Cu (no K reservoir) are stable at 0.5 mA cm-2 for 10 000 min (100 cycles), and at 1 mA cm-2 for 5000 min. The baseline 3D-Cu, planar rGO@Cu, and planar Cu foil fails after 5110, 3012, and 1410 min, respectively.

Sulfur-Grafted Hollow Carbon Spheres for Potassium-Ion Battery Anodes.

Sulfur-rich carbons are minimally explored for potassium-ion batteries (KIBs). Here, a large amount of S (38 wt%) is chemically incorporated into a carbon host, creating sulfur-grafted hollow carbon spheres (SHCS) for KIB anodes. The SHCS architecture provides a combination of nanoscale (≈40 nm) diffusion distances and CS chemical bonding to minimize cycling capacity decay and Coulombic efficiency (CE) loss. The SHCS exhibit a reversible capacity of 581 mAh g-1 (at 0.025 A g-1 ), which is the highest reversible capacity reported for any carbon-based KIB anode. Electrochemical analysis of S-free carbon spheres baseline demonstrates that both the carbon matrix and the sulfur species are highly electrochemically active. SHCS also show excellent rate capability, achieving 202, 160, and 110 mAh g-1 at 1.5, 3, and 5 A g-1 , respectively. The electrode maintains 93% of the capacity from the 5th to 1000th cycle at 3 A g-1 , with steady-state CE being near 100%. Raman analysis indicates reversible breakage of CS and SS bonds upon potassiation to 0.01 V versus K/K+ . The galvanostatic intermittent titration technique (GITT) analysis provides voltage-dependent K+ diffusion coefficients that range from 10-10 to 10-12 cm2 s-1 upon potassiation and depotassiation, with approximately five times higher coefficient for the former.

FeP/C Composites as an Anode Material for K-Ion Batteries.

Owing to their natural abundance, the low potential, and the low cost of potassium, potassium-ion batteries are regarded as one of the alternatives to lithium-ion batteries. In this work, we successfully fabricated a FeP/C composite, a novel electrode material for PIBs, through a simple and productive high-energy ball-milling method. The electrode delivers a reversible capacity of 288.9 mA·h·g-1 (2nd) at a discharge rate of 50 mA g-1, which can meet the future energy storage requirements. Density functional theory calculations suggest a lower diffusion barrier energy of K+ than Na+, which allows faster K+ diffusion in FeP.

Disseminating results: community response and input on Kisumu breastfeeding study.

Communicating findings to study participants and their communities is a practice that often gets overlooked or receives low prioritization by research investigators, but is crucially important. The purpose of this study was to describe the process and community response to the dissemination of results from the Kisumu Breastfeeding Study (KiBS), specifically in terms of (1) community research knowledge and expectations and (2) impressions of result dissemination efforts. A qualitative evaluation was completed for 10 result dissemination events using focus group discussions (FGDs) (n = 10; total number of participants = 98). An inductive, thematic qualitative data analysis was completed in NVivo 8.0. Overall, FGD participants expressed great appreciation for being given information on the study results. Participants had a good understanding of what research entails and had specific expectations for the process, including that the community receive information about the study, not only at the end of the study but also at regular intervals throughout the study's conduct. They also wanted to receive the communications from a credible source, the principal investigator preferably. Other expectations centered on better community and research interactions and development and the use of community collaborators. Impressions of KiBS result dissemination events were positive, but suggestions for the future included having the event in a larger area, inviting more people, having more written materials, and putting the information in an entertaining format such as skits or movies. Sharing study findings with local community members is essential and beneficial to the researchers' long-term engagement with communities and importantly, the successful implementation of study findings when appropriate. It is imperative that dissemination of results be embedded as an integral part of research project planning and development.