https://www.selleckchem.com/products/cfi-400945.html Developing low-cost and highly active bifunctional electrocatalysts for water splitting is very important but still remains a challenge. Herein, a novel bifunctional electrocatalyst composed of CoP and Ni2P nanoparticles implanted in a hollow porous N-doped carbon polyhedron (CoP/Ni2P@HPNCP) is synthesized by carbonization of Co/Ni-layered double hydroxide@zeolitic imidazolate framework-67 (Co/Ni-LDH@ZIF-67) followed by an oxidation and phosphorization strategy. The introduction of LDH can not only promote the formation of a hollow porous structure to supply more active sites, but also generate the CoP/Ni2P nanoheterostructure to afford extra active sites and modulate the electronic structure of the catalyst. As a result, CoP/Ni2P@HPNCP exhibits excellent pH universal hydrogen evolution reaction activity and alkaline oxygen evolution reaction activity. Furthermore, the electrolytic cell assembled from bifunctional CoP/Ni2P@HPNCP requires a cell voltage of 1.59 V in 1.0 M KOH at 10 mA cm-2, revealing its potential as a high performance bifunctional electrocatalyst.Surface-enhanced Raman spectroscopy (SERS) is mainly contributed by "hot spots". Due to the huge electromagnetic enhancement, "hot spots" have wide applications in surface analysis and surface catalysis. The in-depth research on the "hot spots" effect is conducive to understanding SERS enhancement mechanisms and designing substrates with high enhancement. At present, the investigation on the "hot spots" effect is mainly based on theoretical simulation and simple experimental models. However, little attention has been paid to the SERS substrates with practical applications. The main reason is that it is difficult to construct a suitable coupled model with great uniformity and sensitivity, which led to the lack of comparability of SERS intensities from different spots or substrates. In this work, Au nanoparticle mono-/bi-layer films coupled with Au single-c