Reduction of nitroaromatics to the corresponding amines is a key process in the fine and bulk chemicals industry to produce polymers, pharmaceuticals, agrochemicals and dyes. However, their effective and selective reduction requires high temperatures and pressurized hydrogen and involves noble metal-based catalysts. Here we report on an earth-abundant, plasmonic nano-photocatalyst, with an excellent reaction rate towards the selective hydrogenation of nitroaromatics. With solar light as the only energy input, the chalcopyrite catalyst operates through the combined action of hot holes and photothermal effects. Ultrafast laser transient absorption and light-induced electron paramagnetic resonance spectroscopies have unveiled the energy matching of the hot holes in the valence band of the catalyst with the frontier orbitals of the hydrogen and electron donor, via a transient coordination intermediate. Consequently, the reusable and sustainable copper-iron-sulfide (CuFeS2) catalyst delivers previously unattainable turnover frequencies, even in large-scale reactions, while the cost-normalized production rate stands an order of magnitude above the state of the art.

Institute of Electronic Structure and Laser Foundation for Research and Technology Hellas Heraklion Greece

Leibniz Institute for Catalysis Rostock Germany

Nanotechnology Centre Centre of Energy and Environmental Technologies VŠB Technical University of Ostrava Ostrava Poruba Czech Republic

Regional Centre of Advanced Technologies and Materials Czech Advanced Technology and Research Institute Palacký University Olomouc Czech Republic

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Ross, J. R. H. Contemporary Catalysis: Fundamentals and Current Applications (Elsevier, 2019).

Romero NA, Nicewicz DA. Organic photoredox catalysis. Chem. Rev. 2016;116:10075–10166. doi: 10.1021/acs.chemrev.6b00057. PubMed DOI

Blaser HU, et al. Selective hydrogenation for fine chemicals: recent trends and new developments. Adv. Synth. Catal. 2003;345:103–151. doi: 10.1002/adsc.200390000. DOI

Corma A, Serna P. Chemoselective hydrogenation of nitro compounds with supported gold catalysts. Science. 2006;313:332–334. doi: 10.1126/science.1128383. PubMed DOI

Jagadeesh RV, et al. Nanoscale Fe2O3-based catalysts for selective hydrogenation of nitroarenes to anilines. Science. 2013;342:1073–1076. doi: 10.1126/science.1242005. PubMed DOI

Westerhaus FA, et al. Heterogenized cobalt oxide catalysts for nitroarene reduction by pyrolysis of molecularly defined complexes. Nat. Chem. 2013;5:537–543. doi: 10.1038/nchem.1645. PubMed DOI

Li W, et al. General and chemoselective copper oxide catalysts for hydrogenation reactions. ACS Catal. 2019;9:4302–4307. doi: 10.1021/acscatal.8b04807. DOI

Cui JB, et al. Near-infrared plasmonic-enhanced solar energy harvest for highly efficient photocatalytic reactions. Nano Lett. 2015;15:6295–6301. doi: 10.1021/acs.nanolett.5b00950. PubMed DOI

Kaur M, Nagaraja CM. Template-free synthesis of Zn1−xCdxS nanocrystals with tunable band structure for efficient water splitting and reduction of nitroaromatics in water. ACS Sustain. Chem. Eng. 2017;5:4293–4303. doi: 10.1021/acssuschemeng.7b00325. DOI

Goswami, A. et al. Fe(0)-embedded thermally reduced graphene oxide as efficient nanocatalyst for reduction of nitro compounds to amines. Chem. Eng. J. 382, 122469 (2020).

She W, et al. High catalytic performance of a CeO2-supported Ni catalyst for hydrogenation of nitroarenes, fabricated via coordination-assisted strategy. ACS Appl. Mater. Interfaces. 2018;10:17487–17487. doi: 10.1021/acsami.8b06791. PubMed DOI

Gong WB, et al. Nitrogen-doped carbon nanotube confined Co–Nx sites for selective hydrogenation of biomass-derived compounds. Adv. Mater. 2019;31:e1808341. doi: 10.1002/adma.201808341. PubMed DOI

Zhou, P. et al. High performance of a cobalt-nitrogen complex for the reduction and reductive coupling of nitro compounds into amines and their derivatives. Sci. Adv. 3 e1601945 (2017). PubMed PMC

Kumar A, Kumar P, Paul S, Jain SL. Visible light assisted reduction of nitrobenzenes using Fe(bpy)3+2/rGO nanocomposite as photocatalyst. Appl. Surf. Sci. 2016;386:103–114. doi: 10.1016/j.apsusc.2016.05.139. DOI

Chen PQ, et al. A visible-light-responsive metal-organic framework for highly efficient and selective photocatalytic oxidation of amines and reduction of nitroaromatics. J. Mater. Chem. A. 2019;7:27074–27080. doi: 10.1039/C9TA10723A. DOI

Gao WZ, Xu Y, Chena Y, Fu WF. Highly efficient and selective photocatalytic reduction of nitroarenes using the Ni2P/CdS catalyst under visible-light irradiation. Chem. Commun. 2015;51:13217–13220. doi: 10.1039/C5CC04030B. PubMed DOI

Yu ZJ, et al. Photocatalytic hydrogenation of nitroarenes using Cu1.94S–Zn0.23Cd0.77S heteronanorods. Nano Res. 2018;11:3730–3738. doi: 10.1007/s12274-017-1944-1. DOI

Gelle A, et al. Applications of plasmon-enhanced nanocatalysis to organic transformations. Chem. Rev. 2020;120:986–1041. doi: 10.1021/acs.chemrev.9b00187. PubMed DOI

Aslam U, Rao VG, Chavez S, Linic S. Catalytic conversion of solar to chemical energy on plasmonic metal nanostructures. Nat. Catal. 2018;1:656–665. doi: 10.1038/s41929-018-0138-x. DOI

Furube, A. & Hashimoto, S. Insight into plasmonic hot-electron transfer and plasmon molecular drive: new dimensions in energy conversion and nanofabrication. NPG Asia Mater. 9, e454 (2017).

Song YJ, et al. Selective photocatalytic synthesis of haloanilines from halonitrobenzenes over multifunctional AuPt/monolayer titanate nanosheet. ACS Catal. 2018;8:9656–9664. doi: 10.1021/acscatal.8b02662. DOI

Hao CH, et al. Synergistic effect of segregated Pd and Au nanoparticles on semiconducting SiC for efficient photocatalytic hydrogenation of nitroarenes. ACS Appl. Mater. Interfaces. 2018;10:23029–23036. doi: 10.1021/acsami.8b04044. PubMed DOI

Xiao Q, et al. Alloying gold with copper makes for a highly selective visible-light photocatalyst for the reduction of nitroaromatics to anilines. ACS Catal. 2016;6:1744–1753. doi: 10.1021/acscatal.5b02643. DOI

Aslam U, Chavez S, Linic S. Controlling energy flow in multimetallic nanostructures for plasmonic catalysis. Nat. Nanotechnol. 2017;12:1000–1005. doi: 10.1038/nnano.2017.131. PubMed DOI

Linic S, Chavez S, Elias R. Flow and extraction of energy and charge carriers in hybrid plasmonic nanostructures. Nat. Mater. 2021;20:916–924. doi: 10.1038/s41563-020-00858-4. PubMed DOI

Tagliabue G, et al. Ultrafast hot-hole injection modifies hot-electron dynamics in Au/p-GaN heterostructures. Nat. Mater. 2020;19:1312–1318. doi: 10.1038/s41563-020-0737-1. PubMed DOI

Regulacio MD, Han MY. Multinary I-III-VI2 and I2-II-IV-VI4 semiconductor nanostructures for photocatalytic applications. Acc. Chem. Res. 2016;49:511–519. doi: 10.1021/acs.accounts.5b00535. PubMed DOI

Bhattacharyya B, Pandey A. CuFeS2 quantum dots and highly luminescent CuFeS2 based core/shell structures: synthesis, tunability, and photophysics. J. Am. Chem. Soc. 2016;138:10207–10213. doi: 10.1021/jacs.6b04981. PubMed DOI

Ghosh S, et al. Colloidal CuFeS2 nanocrystals: intermediate Fe d-band leads to high photothermal conversion efficiency. Chem. Mater. 2016;28:4848–4858. doi: 10.1021/acs.chemmater.6b02192. PubMed DOI PMC

Sugathan A, et al. Why does CuFeS2 resemble gold? J. Phys. Chem. Lett. 2018;9:696–701. doi: 10.1021/acs.jpclett.7b03190. PubMed DOI

Britt RD, Rao GD, Tao LZ. Bioassembly of complex iron-sulfur enzymes: hydrogenases and nitrogenases. Nat. Rev. Chem. 2020;4:542–549. doi: 10.1038/s41570-020-0208-x. PubMed DOI PMC

Zhang X, et al. Product selectivity in plasmonic photocatalysis for carbon dioxide hydrogenation. Nat. Commun. 2017;8:14542. doi: 10.1038/ncomms14542. PubMed DOI PMC

Brongersma ML, Halas NJ, Nordlander P. Plasmon-induced hot carrier science and technology. Nat. Nanotechnol. 2015;10:25–34. doi: 10.1038/nnano.2014.311. PubMed DOI

Khaledialidusti, R., Mishra, A. K. & Barnoush, A. Temperature-dependent properties of magnetic CuFeS2 from first-principles calculations: structure, mechanics, and thermodynamics. AIP Adv. 9, 065021 (2019).

Bastola E, Bhandari KP, Subedi I, Podraza NJ, Ellingson RJ. Structural, optical, and hole transport properties of earth-abundant chalcopyrite (CuFeS2) nanocrystals. MRS Commun. 2018;8:970–978. doi: 10.1557/mrc.2018.117. DOI

Abdel-Latif IA, Ammar HY. Adsorption and magnetic properties of Cu11MO12 (M = Cu, Ni and Co): ab initio study. Results Phys. 2017;7:4419–4426. doi: 10.1016/j.rinp.2017.11.011. DOI

Litman ZC, Wang YJ, Zhao HM, Hartwig JF. Cooperative asymmetric reactions combining photocatalysis and enzymatic catalysis. Nature. 2018;560:355–359. doi: 10.1038/s41586-018-0413-7. PubMed DOI

Huang GF, et al. The atomic-resolution crystal structure of activated [Fe]-hydrogenase. Nat. Catal. 2019;2:537–543. doi: 10.1038/s41929-019-0289-4. DOI

Yang, Y. J. et al. Porous organic frameworks featured by distinct confining fields for the selective hydrogenation of biomass-derived ketones. Adv. Mater. 32, e1908243 (2020). PubMed

Fukui M, Koshida W, Tanaka A, Hashimoto K, Kominami H. Photocatalytic hydrogenation of nitrobenzenes to anilines over noble metal-free TiO2 utilizing methylamine as a hydrogen donor. Appl. Catal. B. 2020;268:118446. doi: 10.1016/j.apcatb.2019.118446. DOI

Zhang H, et al. P/N co-doped carbon derived from cellulose: a metal-free photothermal catalyst for transfer hydrogenation of nitroarenes. Appl. Surf. Sci. 2019;487:616–624. doi: 10.1016/j.apsusc.2019.05.144. DOI

Zhang S, et al. Photocatalytic organic transformations: simultaneous oxidation of aromatic alcohols and reduction of nitroarenes on CdLa2S4 in one reaction system. Appl. Catal. B. 2018;233:084. doi: 10.1016/j.apcatb.2018.03.084. DOI

Zhang SJ, et al. Ultra-low content of Pt modified CdS nanorods: preparation, characterization, and application for photocatalytic selective oxidation of aromatic alcohols and reduction of nitroarenes in one reaction system. J. Hazard. Mater. 2018;360:182–192. doi: 10.1016/j.jhazmat.2018.07.108. PubMed DOI

Karthik R, et al. A study of electrocatalytic and photocatalytic activity of cerium molybdate nanocubes decorated graphene oxide for the sensing and degradation of antibiotic drug chloramphenicol. ACS Appl. Mater. Interfaces. 2017;9:6547–6559. doi: 10.1021/acsami.6b14242. PubMed DOI

Zhang LQ, et al. Highly active TiO2/g-C3N4/G photocatalyst with extended spectral response towards selective reduction of nitrobenzene. Appl. Catal. B. 2017;203:003. doi: 10.1016/j.apcatb.2016.10.003. DOI

Xu SD, Tang JH, Zhou QW, Du J, Li HX. Interfacing anatase with carbon layers for photocatalytic nitroarene hydrogenation. ACS Sustain. Chem. Eng. 2019;7:16190–16199. doi: 10.1021/acssuschemeng.9b03149. DOI

Challagulla, S., Tarafder, K., Ganesan, R. & Roy, S. Structure sensitive photocatalytic reduction of nitroarenes over TiO2. Sci. Rep. 7, 8783 (2017). PubMed PMC

Kumar, A., Paul, B., Boukherroub, R. & Jain, S. L. Highly efficient conversion of the nitroarenes to amines at the interface of a ternary hybrid containing silver nanoparticles doped reduced graphene oxide/graphitic carbon nitride under visible light. J. Hazard. Mater. 387, 121700 (2020). PubMed

Kong L, Mayorga-Martinez CC, Guan JG, Pumera M. Fuel-free light-powered TiO2/Pt Janus micromotors for enhanced nitroaromatic explosives degradation. ACS Appl. Mater. Interfaces. 2018;10:22427–22434. doi: 10.1021/acsami.8b05776. PubMed DOI

Lin LL, et al. A highly CO-tolerant atomically dispersed Pt catalyst for chemoselective hydrogenation. Nat. Nanotechnol. 2019;14:354–361. doi: 10.1038/s41565-019-0366-5. PubMed DOI

Atomic Scale Engineering of Multivalence-State Palladium Photocatalyst for Transfer Hydrogenation with Water as a Proton Source

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