Zhang Zhexuan, born on August 11, 1992, also known as Xiao Leer, is the lead singer of Penicillin Band.

1. In 2012, Zhang Zhexuan and his friends formed the Penicillin Band and officially started his career as a singer. In December 2013, Zhang Zhexuan released the album "PENICILLIN" with the band. Later, in 2013, he and the band participated in many concerts such as Beidaihe 6789 Music Festival, Hefei Aishang Carnival, and School (Influence on the Sound of Urban Music). In May 2014, due to Zhang Zhexuan's plan to study abroad, the band temporarily disbanded. It was not until April 2017 that Penicillin reunited and returned and released the album "Embrace the World". In 2017, Zhang Zhexuan started touring with the Penicillin Band and toured 16 cities in China in two months. In January of the following year, the band participated in the 2017/18 Shenzhen New Year Midi Concert and won the honor of Best New Rock Artist of the Year at the 9th China Rock Midi Awards in 2017, which was recognized.

2. In May 2019, Zhang Zhexuan participated in the music variety show "Summer of the Band" with the band. And in the following August, the band advanced to the HOT5 finals list, and Zhang Zhexuan and the band further increased their popularity. In October, Zhang Zhexuan was selected into the 2019 Forbes China 30 Under 30 list.