Fig. 2
From: WS2–WC–WO3 nano-hollow spheres as an efficient and durable catalyst for hydrogen evolution reaction

FE-SEM images of a–c the WS2 NFs and d–f WS2–WC–WO3 NH spheres at different scales
From: WS2–WC–WO3 nano-hollow spheres as an efficient and durable catalyst for hydrogen evolution reaction
FE-SEM images of a–c the WS2 NFs and d–f WS2–WC–WO3 NH spheres at different scales