Search

Using the electrochemical CO2reduction reaction (CO2RR) with Cu-based electrocatalysts to achieve carbon-neutral cycles remains a significant challenge because of its low selectivity and poor stability. Modulating the surface electron distribution by defects engineering or doping can effectively improve CO2RR performance. Herein, we synthesize the electrocatalyst of Vo-CuO(Sn) nanosheets containing oxygen vacancies and Sn dopants for application in CO2RR-to-CO. Density functional theory calculations confirm that the incorporation of oxygen vacancies and Sn atoms substantially reduces the energy barrier for *COOH and *CO intermediate formation, which results in the high efficiency, low overpotential, and superior stability of the CO2RR to CO conversion. This electrocatalyst possesses a high Faraday efficiency (FE) of 99.9% for CO at a low overpotential of 420 mV and a partial current density of up to 35.22 mA cm–2at −1.03 V versus reversible hydrogen electrode (RHE). The FECOof Vo-CuO(Sn) could retain over 95% within a wide potential area from −0.48 to −0.93 V versus RHE. Moreover, we obtain long-term stability for more than 180 h with only a slight decay in its activity. Therefore, this work provides an effective route for designing environmentally friendly electrocatalysts to improve the selectivity and stability of the CO2RR to CO conversion.

Suppressing the recombination of light-induced carriers in semiconductor photocatalysts is crucial but challenging for high-activity photocatalysis. In addition to the current substantially developed strategies, such as the built-in field of catalytic heterostructures, other promising alternatives need to be explored. Herein, a mangosteen peel waste-derived 3D graphene hybrid material with a magnetic interfacial junction was constructed to obtain insights into its highly efficient photocatalytic performance by boosting carrier transfer efficiency with the assistance of a magnetic field. The spin-related behavior of the ferromagnetic alignment of the magnetic interfacial junction of the designed 3D graphene/Cd0.5Zn0.5S hybrids plays an essential role in improving the photocatalytic performance, with ciprofloxacin degradation efficiency reaching 95% removal in 15 min, which is a 67% reduction in photocatalytic degradation time. This photocatalytic performance is outstanding in comparison to previous research without an applied external magnetic field. With low energy consumption, this magnetic field strategy provides a new perspective for water treatment as well as various catalytic fields.

The electrochemical CO2reduction reaction (CO2RR) to HCOOH offers a promising strategy for a carbon-neutral cycle. Sn-Based materials have been demonstrated as applicable in extensive studies of CO2RR to HCOOH, but great challenges still remain, including the weak CO2adsorption and narrow potential window as well as low stability. Herein, we developed ultrasmall Sn nanoparticles inlaid on N/P-doped carbon (Sn@NPC) composites by an upcycling design using Sn electroplating sludge. The obtained Sn@NPC electrode exhibited a higher Faradaic efficiency of 87.93% for HCOOH at 1.05 V vs.RHE and an FE over 80% within a 500 mV broad potential window. Moreover, the Sn@NPC electrode achieved excellent long-term stability up to 105 h, which was superior to that of most Sn-based catalysts in similar systems. Density functional theory calculations demonstrated that Sn@NPC could enhance CO2adsorption, which led to stronger *OCHO adsorption, weaker *HCOOH adsorption and faster electron/mass transport. This work may provide a promising lead for recycling metal from electroplating sludge and for the design of efficient and stable catalysts for the CO2RR.

Online ride-hailing services play a crucial role in daily transportation, However, challenges persist in certain regions with limited access, and drivers encounter difficulties in receiving orders. Accurate prediction of short-term origin-destination (OD) demand is crucial for addressing these issues. This study leverages recent advancements in artificial intelligence and big data to introduce a spatiotemporal encoder-decoder network with a residual feature extractor (RF-STED) for short-term OD demand prediction in online ride-hailing services. The RF-STED model, built on deep learning models such as graph convolutional networks and convolutional long short-term memory (Conv-LSTM), includes spatiotemporal networks, encoding layers, and a residual feature extractor. The spatiotemporal network has two branches: branch one processes multi-pattern OD data using a multi-pattern temporal feature extraction module, utilizing a multi-channel Conv-LSTM to capture temporal correlations. Branch two utilizes a multi-spatial feature extraction module to convert OD pair associations into a spatial topology, extracting multi-spatial correlations. The encoding layer captures spatiotemporal dependencies, while the residual feature extractor decodes compressed vectors back into an OD graph for forecasting future demand. Experiments with a Manhattan taxi dataset in the U.S. show the RF-STED model outperforms 10 baseline models and four ablation models. The results emphasize the model’s strength and robustness in short-term OD flow prediction.

While the issues of childlessness and social support in old age have received considerable attention in more developed countries, the phenomenon of aging without children in China has been relatively underexplored. The existing, albeit limited, literature highlights the vulnerability of the childless elderly in China and the inadequacy of social care services, which is predominantly directed toward most impoverished groups. This study examines the care arrangements and social support mechanisms for childless older people in urban China, emphasizing the role of community-level officers in this context. Drawing on in-depth interviews conducted in 2019 with 27 childless elderly individuals and 10 community-level officers in Shanghai, the study reveals the formation of community-based substitute families. These substitute families, comprising neighbors, extended family members, and friends, provide daily assistance, emotional support, and sometimes intensive care. The establishment of these substitute families hinges on the childless individuals’ ability to navigate public and social resources, as well as the institutionalized mobilization and informal work strategies of community-level officers. We argue that the care arrangements for childless older people are significantly shaped by the state's aging-in-place elder care policy. However, the effectiveness of this policy is mediated by the informal work strategies of community-level officers and the proactive care planning by the childless elderly themselves. Our findings offer important insights for improving the current family-based elder care policies and enrich our understanding of aging without children in urban China.

The cobalt-based spinel oxides MCo2O4(M = Ni, Mn, Cu, Fe, etc.) have garnered significant attention due to their potential applications in energy storage. In this study, ultra-thin FeCo2O4nanosheets have been synthesized through a facile electrodeposition method and used as binder-free electrodes for high-performance supercapacitors. The results indicate that the FeCo2O4nanosheet (FCS) electrode obtained through 5 min of electrodeposition using ferrous salt (FeSO4) as the precursor has a more abundant pore structure and exhibits the best electrochemical performance. The specific capacitance of the FeCo2O4nanosheets electrode reaches 679 F g−1at a current density of 1 A g−1, and it retains 92.9 % of its initial capacitance after undergoing 5000 cycles. In addition, the assembled FeCo2O4nanosheet (FCS)//activated carbon (AC) asymmetric supercapacitor shows a high energy density of 62.5 Wh kg−1at 750 W kg−1and with a capacitance retention of 91.3 % after 5000 cycles. Furthermore, the electrodeposition method utilized in the synthesis of the FeCo2O4nanosheets is cost-effective, environmentally friendly, and can be employed to fabricate other MCo2O4materials with superior electrochemical properties.