Dual-Printed Soil Sensors for Nitrate and Moisture Monitoring

Underground Ink: Printed Electronics Enabling Electrochemical Sensing in Soil

“…These advantages are key for detecting ions in soil [46]. Various voltammetry techniques have been used for detecting ions in soil, such as cyclic voltammetry (CV) [23,24,[47][48][49][50][51][52][53][54][55][56], square wave voltammetry (SWV) [50,[57][58][59], and differential pulse voltammetry (DPV) [60]. While all of these techniques involve sweeping a voltage across the working electrode as a function of time, the waveform differs for each voltametric technique.…”

“…Yin et al developed and constructed a dual-printed sensor for detecting nitrate and moisture using silver nanoparticle inks on Kapton films with aerosol jet printing. The nitrate sensor was able to detect nitrate levels from 1 to 400 mg/mL using cyclic voltametric techniques with a scan rate of 150 V/s [48]. Chen et al developed cadmium sulfide nanorods modified screen-printed electrodes (CdS NRs-SPE), coupled with a portable potentiostat and an extraction filter that could detect nitrate levels in soil samples in less than 10 min [23].…”

“…Yin et al developed and constructed a dual-printed sensor for detecting nitrate and moisture using silver nanoparticle inks on Kapton films with aerosol jet printing. The nitrate sensor was able to detect nitrate levels from 1 to 400 mg/mL using cyclic voltametric techniques with a scan rate of 150 V/s [48].…”

Aerosol‐Jet Printed Sensors for Environmental, Safety, and Health Monitoring: A Review

“…[ 46 ] While metal nanoparticles can be dispersed into inks using facile methods, their production requires both higher labor and energy input, stabilizers are often required to prevent agglomeration, and postprocessing methods require high temperatures. In the class of metal oxides, several examples have recently appeared: particulate, [ 47 ] metal composite, [ 44 ] and nanowire‐based [ 48 ] tin oxides, iron oxides, [ 49 ] zinc oxides, [ 50 ] and nickel oxides. [ 51 ] It is worth noting that superparamagnetic iron oxide‐based inks (Fe 3 O 4 ) have been recently demonstrated using AJP onto both rigid and flexible platforms to execute movements including rotation, translation, and out‐of‐plane bending, which could potentially benefit various biomedical and soft robotics applications.…”

“…When placed in sandy soil, the dual printed sensors demonstrated agriculturally relevant readings. [ 49 ] As the manufacturing demand toward low‐cost, flexible, and biodegradable platforms has increased, paper substrates have gained considerable attention as attractive candidates for printing electronic devices. To this end, recently, a low‐cost capacitive‐type R H sensor consisting of printed interdigitated architecture on paper was fabricated for critical infrastructure health monitoring purposes, which showed ability to measure humidities in the range of 20% to 90% R H .…”