Figure 2.

(a) XPS survey spectrum, (b) Cu 2p, (c) In 3d, and (d) Se 3d core-level spectrum of the CuInSe2 nanoparticles synthesized at 200 °C for 24 h

(a) XPS survey spectrum, (b) Cu 2p, (c) In 3d, and (d) Se 3d core-level spectrum of the CuInSe2 nanoparticles synthesized at 200 °C for 24 h