Programming Bifunctional Metal–Organic Frameworks to Integrate Multiple Triboelectric Nanogenerators for Green Electronics toward Effective Self-Powered Photocatalytic System
Yue Zhang, Yue Zhang, Yingying Zhang, Yingying Zhang, Lin Zhang, Qi Qin, Yuanmeng Tao, Jiaxing Cui, Dandan Wang, Chao Huang, Hongwei Hou
Abstract
Programming and synthesizing bifunctional materials for regulating the output of triboelectric nanogenerators (TENGs) and their photocatalytic efficiency is a promising strategy for energy harvesting to build self-powered systems. Herein, we tackle this challenge by introducing metal–organic frameworks (MOFs) as molecular catalysts and triboelectric layers for self-powered photocatalytic systems. A zeolite-like mixed-valence MOF ( Cu I Cu II -1 ) and a ladder-structured MOF ( Cu II -2 ) were obtained through structural transformation. Due to the excellent charge-trapping capability and surface potential of Cu I Cu II -1, the outputs of Cu I Cu II -1-TENG (a short-circuit current ( I sc ) of 30.4 μA and an open-circuit voltage ( V oc ) of 524.1 V) were significantly superior to those of Cu II -2-TENG . The incorporation of Cu I Cu II -1 with ethylcellulose (EC) to form Cu I Cu II -1@EC composite films greatly improved the TENG outputs, and the 10% Cu I Cu II -1@EC-TENG offered the maximum I sc (57.2 μA) and V oc (986.8 V). Furthermore, multiple 10% Cu I Cu II -1@EC-TENG devices were integrated in parallel to assemble multiple TENG devices ( M-TENG ) to harvest biomechanical energy, which displayed significant potential to continuously power blue LEDs, generating blue-light irradiation to trigger the photocatalytic C(sp)–H/Si–H cross-coupling reactions of aromatic alkyne and trimethylsilane for alkynylsilane over the photocatalysts Cu I Cu II -1 and Cu II -2 . The results revealed that Cu I Cu II -1 achieved a cooperative effect on remarkable catalytic selectivity and activity. This work demonstrates that bifunctional MOFs can serve as friction electrode materials for the large-scale integration and assembly of MOF-based TENG, and photocatalysts for achieving self-powered photocatalytic systems.