*Review* **Metal/Semiconductor Nanocomposites for Photocatalysis: Fundamentals, Structures, Applications and Properties**

#### **Yong-sheng Fu, Jun Li \* and Jianguo Li**

School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; fuys648@163.com (Y.-s.F.); lijg@sjtu.edu.cn (J.L.)

**\*** Correspondence: li.jun@sjtu.edu.cn; Tel.: +86-156-0189-7272

Received: 1 February 2019; Accepted: 19 February 2019; Published: 4 March 2019

**Abstract:** Due to the capability of utilizing light energy to drive chemical reactions, photocatalysis has been widely accepted as a green technology to help us address the increasingly severe environment and energy issues facing human society. To date, a large amount of research has been devoted to enhancing the properties of photocatalysts. As reported, coupling semiconductors with metals is one of the most effective methods to achieve high-performance photocatalysts. The excellent properties of metal/semiconductor (M/S) nanocomposite photocatalysts originate in two aspects: (a) improved charge separation at the metal-semiconductor interface; and (b) increased absorption of visible light due to the surface plasmon resonance of metals. So far, many M/S nanocomposite photocatalysts with different structures have been developed for the application in environmental remediation, selective organic transformation, hydrogen evolution, and disinfection. Herein, we will give a review on the M/S nanocomposite photocatalysts, regarding their fundamentals, structures (as well as their typical synthetic approaches), applications and properties. Finally, we will also present our perspective on the future development of M/S nanocomposite photocatalysts.

**Keywords:** nanocomposite photocatalyst; environmental remediation; selective organic transformation; hydrogen evolution; disinfection
