*
Corresponding authors
a
Low Energy Electronic Systems (LEES), Singapore-MIT Alliance for Research and Technology (SMART), 1 Create Way, Singapore 138602, Singapore
E-mail:
zhe.liu@nwpu.edu.cn, buonassi@mit.edu
b
Solar Energy Research Institute of Singapore (SERIS), National University of Singapore, 7 Engineering Drive, Singapore 117574, Singapore
c
Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Singapore 138634, Singapore
d
Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), 77 Massachusetts Ave., Cambridge, MA 02139, USA
e
Institute for Infocomm Research (I2R), Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, Singapore 138632, Singapore
f
Institute of Sustainability for Chemicals, Energy and Environment, Agency for Science, Technology and Research (A*STAR), 1 Pesek Rd, Singapore 627833, Singapore
g
Department of Chemistry, The University of British Columbia (UBC), 2036 Main Mall, Vancouver, Canada
h
Department of Mathematics, National University of Singapore (NUS), 21 Lower Kent Ridge Rd, Singapore 119077, Singapore