摘要：The development of inexpensive and efficient Pt-free electrocatalysts for the hydrogen evolution reaction(HER)is greatly crucial for water *** carbide(WC)exhibiting a Pt-like electronic structure represents an attractive alternative,although its overall performance is limited by the strong W-H bond that impedes hydrogen ***,we employed an in-situ interface engineering strategy to construct high-performance and cost effective electrocatalysts comprising WC/tungsten phosphide(WP)heterostructures that were anchored on N,P-codoped carbon(WC/WP@NPC)via a one-step pyrolysis of a melamine polyphosphate/WO_(3) hybrid in an inert *** to the crystal structure compatibility and electron-rich property of WP,it optimizes the electronic structure and hydrogen adsorption configuration of WC,thus significantly weakening the W-H bond with a thermoneutral Gibbs free energy of hydrogen adsorption(ΔG_(H^(*)))of−0.05 ***,NPC ensures fast electron transport and structural stability of the WC/WP@NPC ternary *** synergistically lead to outstanding HER performances of the catalyst in acidic and alkaline *** finding offers a new strategy for designing Pt-alternative electrocatalysts with outstanding electrochemical performances for high-efficiency water splitting and other applications.

摘要：对石墨烯进行功能化处理,可得到具有合适层间距和较高离子扩散速率的理想石墨烯基电极材料,其作为钠离子电池负极材料有着重要的应用潜力。通过在石墨烯结构中进行原位插层反应,成功制备出聚对苯乙烯磺酸钠(PSS)插层的石墨烯复合材料(PSS-rGO)。这种插层结构是基于石墨烯的π电子可以与PSS结构中的π电子相互作用,使得石墨烯层间距增大并抑制其堆积。同时,PSS中的磺酸钠基团可有效提高钠离子扩散速率,增强电极对钠离子的吸附能力,从而提升钠离子电池的循环性能。利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射仪(XRD)、拉曼光谱仪(Raman)、X射线光电子能谱仪(XPS)、电化学工作站和多通道电池综合测试仪对样品进行测试分析。结果表明,PSS-rGO电极在5 A·g^(-1)的电流密度下循环6000圈后容量可保持在256 mAh·g^(-1),单圈衰减率为0.003%,表现出优异的循环性能。本研究为开发高比容、快速储钠以及长寿命的钠离子电池负极材料提供了可行思路。

摘要：西藏干旱地区水分蒸发强,盐分被毛细水运移至地表,常引发表面土壤盐渍化。不恰当的灌溉方式,可能会加重盐渍化程度或产生新的盐渍化现象。以拉洛水利枢纽配套曲美灌区为例,初步分析研究灌区水文地质环境现状,预测受灌后灌区水文地质条件的变化、发展趋势及对土壤盐渍化评价、改良措施建议,可为我国西藏地区灌区建设提供借鉴。