The editorial team and editorial board of Journal of Materials Chemistry A (Impact factor: 14.511) have recently selected the journal's 2021 Outstanding Reviewers. Outstanding reviewers were publicly announced, and each will receive a certificate recognizing their contribution. Professor Chia-Wen (Kevin) Wu has received this honor. They selected the Outstanding Reviewers for 2021 based on several criteria, including the number, timeliness, and quality of reports completed in the past 12 months. In addition to reviewers who provide a large number of high-quality reports, they also value reviewers who provide comprehensive and detailed reports. Reviewers who provide clear and insightful reports, and those who do extra to help authors improve their manuscripts are appreciated as well.