  As the use of triboelectric nanogenerators (TENGs) increases, the generation
of related electronic waste has been a major challenge. Therefore, the
development of environmentally friendly, biodegradable, and low-cost TENGs must
be prioritized. Having discovered that plant proteins, by-products of grain
processing, possess excellent triboelectric properties, we explore these
properties by evaluating the protein structure. The proteins are recycled to
fabricate triboelectric layers, and the triboelectric series according to
electrical properties is determined for the first time. Using a special
structure design, we construct a plant-protein-enabled biodegradable TENG by
integrating a polylactic acid film, which is used as a new type of mulch film
to construct a growth-promoting system that generates space electric fields for
agriculture. Thus, from the plant protein to the crop, a sustainable recycling
loop is implemented. Using bean seedlings as a model to confirm the feasibility
of the mulch film, we further use it in the cultivation of greenhouse
vegetables. Experimental results demonstrate the applicability of the proposed
plant-protein-enabled biodegradable TENG in sustainable agriculture.
