Uniform zinc-ion deposition regulated by thin sulfonated poly(ether ketone) layer for Stabilizing Zn anodes.

Aqueous zinc-ion batteries (AZIBs) have been getting lots of attention in the field of large scale energy storage owing to their low cost, large capacity and excellent safety. However, Zn anodes have serious dendritic growth and corrosion hydrogen evolution issues, which hinder their further application. Herein, a simple drop-coating technique was used to build a thin sulfate poly(ether ketone) (SPEEK) solid-electrolyte interphase (SEI) on the surface of the Zn anode to address these issues. The sulfonated group (-SO3-） in SPEEK can provide rich coordination sites for Zn2+, controlling the uniform deposition of Zn2+. Therefore, the polymer SEI can block electrolytes and homogenize the Zn2+flux, resulting that the modified Zn (SPEEK@Zn) anode could effectively limit the formation of dendrites and side reactions. At a current density of 0.5 mA cm-2, SPEEK@Zn electrodes can maintain an ultra-long plating/stripping cycle life of 1000 h. Full batteries based on SPEEK@Zn have more superior cycle stability than the bare ones. This approach offers a straightforward and scalable remedy for high-performance Zn anode batteries.

Electrical-Conductive/Insulating Bi-Functional Layers for Stable Zn Metal Anode.

Zinc-ion batteries are regarded as an extremely promising candidate for large-scale energy storage equipment due to the inexpensive ingredients and high safety. However, dendrite growth and side reactions occur in the Zn anode, which lead to exceedingly low coulombic efficiency (CE) and poor cycling stability. In this work, we propose a strategy of a conductive/insulating bi-functional coating layer (CIBL) for stable Zn metal anodes. Porous Ag nanowires (NWs) coating as a conductive layer effectively reduces the nuclear barrier and contains Zn2+ deposition in a certain space. Polyimide (PI) coatings as insulating layer implement a shunting effect on Zn2+ , which could reduce the differential concentration on the Zn surface and induce uniform deposition of Zn2+ . Therefore, the CIBL-Zn//CIBL-Zn battery achieves stable plating/stripping of over 1300 h at 1 mA cm-2 . The CE of CIBL-Zn//CIBL-Zn battery maintains at 99.2 % even after 1000 cycles. Moreover, the CIBL-Zn//V2 O5 battery exhibits a capacity of nearly 289.2 mA h g-1 at 5 A g-1 after 3000 cycles and no sign of capacity degradation is found, which further demonstrate the feasibility of this strategy in practical application.

Noble metal-free 0D-1D NiCoP/Mn0.3Cd0.7S nanocomposites for highly efficient photocatalytic H2 evolution under visible-light irradiation.

Efficient and noble metal-free co-catalyst loading is an effective solution for separating and transferring photo-generated carriers and lowering the overpotential in photocatalytic H2 evolution activity. In this work, we designed and prepared a series of novel NiCoP/Mn0.3Cd0.7S (NCP/MCS) composites by modifying MCS nanorods with the co-catalyst NCP using a simple calcination method. Notably, the 10-NCP/MCS composite displays the optimum photocatalytic H2 evolution rate of 118.5 mmol g-1 h-1 under visible-light irradiation. This is approximately 3.39 times higher than that of pure MCS. The corresponding apparent quantum efficiency is 10.2% at 420 nm. The superior photocatalytic activity of the NCP/MCS composites can be attributed to the efficient separation of photogenerated carriers caused by the intimate heterojunction interface between NCP and MCS, smaller transfer resistance, and lower overpotential of NCP. Moreover, the NCP/MCS composites exhibit remarkable photostability. A plausible mechanism is proposed.