Self-powered analytical chemistry: Concept, functionality with circular and eco-design

Self-powered analytical chemistry (SPAC) couples the energy-generating and analytical functions of an analytical device, so that the analyte, the sample matrix or the ambient environment supplies the energy required for the analytical measurement. This review critically examines whether energy autonomy in SPAC necessarily translates into improved sustainability. A quantitative energy-autonomy framework is proposed based on the ratio of autonomously harvested/generated energy to the total measurement-cycle energy demand, enabling classification according to three established energy-harvesting system topologies: autonomous harvesting, autonomous hybrid harvesting, and battery-supplemented harvesting. Enzymatic and microbial biofuel cells, photoelectrochemical and photocatalytic fuel cells, metal–air cells, triboelectric and piezoelectric nanogenerators, photovoltaic systems, and hybrid harvesters are comparatively assessed in terms of analytical performance, power stability, scalability, technology readiness, and sustainability. Photoelectrochemical platforms generally provide the strongest analytical figures of merit, whereas microbial fuel cells and photovoltaic systems offer greater power stability. Mechanical nanogenerators remain largely semi-quantitative unless energy harvesting is decoupled from signal transduction. Recognition strategies, including molecularly imprinted polymers (MIPs), are also evaluated with respect to selectivity, fouling resistance, stability, and cost. Available greenness assessments and limited life-cycle evidence indicate that eliminating batteries does not inherently ensure sustainability, particularly when noble metals, semiconductors, synthetic polymers, or energy-intensive fabrication are required. Standardized energy-autonomy metrics, real-sample and human validation, greener MIP synthesis, and design for recyclability or biodegradability are therefore essential for translating SPAC into regulated environmental, food-safety, and clinical applications.