* Corresponding authors

^a School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore
E-mail: tang0212@ntu.edu.sg, ASZChen@ntu.edu.sg

^b National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou 215123, China
E-mail: yklai@suda.edu.cn

^c Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA

^d Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA