MINI-REVIEW Biological synthesis of nanosized sulfide semiconductors: current status and future prospects João Pinto da Costa 1 & Ana Violeta Girão 2 & Tito Trindade 2 & Maria Clara Costa 3 & Armando Duarte 1 & Teresa Rocha-Santos 1 Received: 21 May 2016 /Revised: 24 July 2016 /Accepted: 27 July 2016 # Springer-Verlag Berlin Heidelberg 2016 Abstract There have been extensive and comprehensive re- views in the field of metal sulfide precipitation in the context of environmental remediation. However, these works have focused mainly on the removal of metals from aqueous solu- tions—usually, metal-contaminated effluents—with less em- phasis on the precipitation process and on the end-products, frequently centering on metal removal efficiencies. Recently, there has been an increasing interest not only in the possible beneficial effects of these bioremediation strategies for metal- rich effluents but also on the formed precipitates. These metal sulfide materials are of special relevance in industry, due to their optical, electronic, and mechanical properties. Hence, identifying new routes for synthesizing these materials, as well as developing methodologies allowing for the control of the shape and size of particulates, is of environmental, economic, and practical importance. Multiple studies have shown proof-of-concept for the biological synthesis of inor- ganic metallic sulfide nanoparticles (NPs), resorting to varied organisms or cell components, though this information has scarcely been structured and compiled in a systematic manner. In this review, we overview the biological synthesis method- ologies of nanosized metal sulfides and the advantages of these strategies when compared to more conventional chemi- cal routes. Furthermore, we highlight the possibility of the use of numerous organisms for the synthesis of different metal sulfide NPs, with emphasis on sulfate-reducing bacteria (SRB). Finally, we put in perspective the potential of these methodologies in the emerging research areas of biohydrometallurgy and nanobiotechnology for the uptake of metals in the form of metal sulfide nanoparticles. A more complete understanding of the principles underlying the (bio)chemistry of formation of solids in these conditions may lead to the large-scale production of such metal sulfides, while simultaneously allowing an enhanced control over the size and shape of these biogenic nanomaterials. Keywords Metal sulfides . Nanoparticles . Biological synthesis Introduction Metal sulfides have been the focal point of much attention in numerous areas of research, with a particular emphasis on optoelectronics and catalysis in particular (Kolb et al. 2011; Paul et al. 2008; Vít 2007). These materials play a major role in industrial processes, such as hydrocracking in fuel refiner- ies (Cui et al. 2011; dos Santos et al. 1999; Sweeny et al. 1987), hydroprocessing (Hensen and van Veen 2003; Shimada 2003), and oxygen reduction in fuel cells (da Rosa 2013; Pan et al. 2012; Shih et al. 2013). At the nanoscale, metal sulfides are used in photocatalysis (Kolb et al. 2011; Luo et al. 2012), optoelectronics (Murugadoss 2013), plant protection and nutrition (Ghormade et al. 2011), and as anti- microbial agents in textile modification technologies (Dastjerdi and Montazer 2010). Moreover, metal sulfide nanocrystals are of particular interest as nanocrystals due to their size-dependent behavior (Liu et al. 2003; Patel et al. 2012), namely, as surface coatings (Rafea et al. 2013; Wei * João Pinto da Costa jpintocosta@ua.pt; joao.pinto.da.costa@gmail.com 1 Department of Chemistry—CESAM, University of Aveiro, 3810-193, Aveiro, Portugal 2 Department of Chemistry—CICECO, University of Aveiro, 3810-193 Aveiro, Portugal 3 CCMAR, University of the Algarve, Campus Gambelas, 8005-139 Faro, Portugal Appl Microbiol Biotechnol DOI 10.1007/s00253-016-7756-5