Tin can telephone-inspired self-powered mechanical wave communication integrated with self-charge excitation triboelectric nanogenerator

As an alternative to electromagnetic wave communication, mechanical waves (MW) retain their advantage in several aspects, including cost-effectiveness, simplicity, interference resistance, and short-distance transmission. Here, a string-vibrated self-powered mechanical wave communication system (SSMWC) is proposed. Inspired by tin can telephone, modulated voltage signals are converted into MW by a vibrator and then transmitted along a string to the receiver. The receiver integrates a string-vibrated triboelectric nanogenerator (SV-TENG) and a self-charge excitation triboelectric nanogenerator (SCE-TENG). The SV-TENG can detect MW and convert them into electrical signals without external power sources, while the SCE-TENG is integrated to improve the sensitivity of the receiver. After charges pumping of SCE-TENG, the average output of SV-TENG can increase by 88 times within the frequency range of 0–1000 Hz, indicating the successful application of self-charge excitation in triboelectric sensing for the first time. Furthermore, a demonstration of information coding and real-time decoding proves the potential application of SSMWC as an alternative in specific environments. This work shows the breakthrough of the bottlenecks faced by triboelectric sensors that the essential preparatory contact electrification before packaging, which indeed affect sensitivity and durability. Therefore, this scheme can be widely applied for output enhancement, especially for triboelectric sensors with lower output.