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Abstract and Figures

Present vision restoration technologies have substantial constraints that limit their application in the clinical setting. In this work, we fabricated a subretinal nanoprosthesis using tellurium nanowire networks (TeNWNs) that converts light of both the visible and near-infrared–II spectra into electrical signals. The broad-spectrum coverage is made possible by a combination of narrow bandgaps, strong absorption, and engineered asymmetries. Implanted into blind mice, the TeNWNs restored pupillary reflexes and enabled visually cued learning under visible and near-infrared 1550-nanometer light. In nonhuman primates, TeNWNs elicited robust retina-derived neural responses, confirming biocompatibility and feasibility. By restoring lost photosensitivity and extending vision to near-infrared, this nanoprosthesis offers a promising approach for restoring vision.

Lattice and photocurrent calculations of Te. (A) Schematics of Te-chain asymmetric atomic structure. The gray dashed boxes indicate the unit cell of each structure. (B) SEM (left) and HAADF-STEM (right) for TeNWNs. The middle panel shows a magnified view of a single Te nanowire from the boxed region of the left image, radially oriented in the c-axis direction. The STEM image shows the defects as indicated by the red dashed circles. (C) The proposed device model for Te photocurrent calculations. Red, blue, and gray circles highlight the internal defects (that is, Sn substitutions, Te vacancies) and external interface effects (electrode channel), respectively. (D) Photocurrent response of Te under zero bias, covering VIS to NIR-II wavelengths. The simulated model for photocurrent calculations consists of Au electrodes and a 12-nm-long Te channel with a Sn substitution. J SC , short-circuit current density. (E) Calculated photocurrent densities of intrinsic, substitution, vacancy, and interface models in NIR-I (954 nm) and NIR-II (1550 nm) bands. Sn substitution or Te vacancy defects and electrode-channel interface effects all enhance the photocurrents. The intrinsic model refers to the one with heavily doped Te as the electrodes in photocurrent calculations, and the photocurrent densities in the intrinsic model are magnified 100 times for visibility.

Lattice and photocurrent calculations of Te. (A) Schematics of Te-chain asymmetric atomic structure. The gray dashed boxes indicate the unit cell of each structure. (B) SEM (left) and HAADF-STEM (right) for TeNWNs. The middle panel shows a magnified view of a single Te nanowire from the boxed region of the left image, radially oriented in the c-axis direction. The STEM image shows the defects as indicated by the red dashed circles. (C) The proposed device model for Te photocurrent calculations. Red, blue, and gray circles highlight the internal defects (that is, Sn substitutions, Te vacancies) and external interface effects (electrode channel), respectively. (D) Photocurrent response of Te under zero bias, covering VIS to NIR-II wavelengths. The simulated model for photocurrent calculations consists of Au electrodes and a 12-nm-long Te channel with a Sn substitution. J SC , short-circuit current density. (E) Calculated photocurrent densities of intrinsic, substitution, vacancy, and interface models in NIR-I (954 nm) and NIR-II (1550 nm) bands. Sn substitution or Te vacancy defects and electrode-channel interface effects all enhance the photocurrents. The intrinsic model refers to the one with heavily doped Te as the electrodes in photocurrent calculations, and the photocurrent densities in the intrinsic model are magnified 100 times for visibility.\ \ …

Experimentally measured photocurrents under optoelectronic and electrophysiological platforms. (A) Photocurrent density output curves of Te devices at varying laser intensities under NIR-II (1550 nm) stimulation. There are distinct photocurrents under zero bias (as indicated by the red dashed lines) and an increase with higher intensities. (B) Photocurrent densities of Te devices varying with laser intensity in different laser bands, including VIS (520 nm), NIR-I (1060 nm), and NIR-II (1550 and 2000 nm). The photocurrents increase linearly with intensity in all bands, and the dashed lines indicate the linear fitting. (C) Photocurrent density statistics for different types of materials under zero bias, including 1D [TeNWNs, WS 2 nanotubes (32)], 2D [CuInP 2 S 6 (33)], and 3D [BiFeO 3 (34), LiNbO 3 (35), KBNNO (36), halide (37), PLZTN (38), TTF-CA (39), BaTiO 3 (40), BBLT (41)] materials. As the dimension decreases, photocurrents show an elevated trend. TeNWNs exhibit the highest photocurrent densities available, benefiting from asymmetries due to both external interface effects and internal defects. (D) Summary of photosensitivity restored using different materials and mechanisms [Si-PV (14-16), NW-PV (42), capacitive (43), WC (1), rods-PT (4)]. Because of a narrow bandgap, high light absorption, and photoelectric conversion, TeNWNs push the photosensitivity from the VIS to a record NIR-II band (1550 nm, light red region), as illustrated by the red arrow. NW, nanowire; PT, photothermal; PV, photovoltaics; WC, wavelength conversion. (E) Schematic of TeNWN photocurrent testing under an electrophysiological platform, which integrates the multielectrode array, digital micromirror device (DMD), and 635 nm laser. A VIS laser (635 nm) was used to illuminate the DMD, which projected patterns onto the surface of TeNWNs. (F) Voltage response on the surface of the TeNWNs under a 635-nm laser visual pattern (circle and triangle) illumination. The color distribution is linearly mapped to the amplitude of voltage response on the surface of the TeNWNs. Laser intensity is 42.5 mW mm −2 , and the recording area is 1200 μm by 1200 μm. The corresponding projection pattern is shown at the top left.

Experimentally measured photocurrents under optoelectronic and electrophysiological platforms. (A) Photocurrent density output curves of Te devices at varying laser intensities under NIR-II (1550 nm) stimulation. There are distinct photocurrents under zero bias (as indicated by the red dashed lines) and an increase with higher intensities. (B) Photocurrent densities of Te devices varying with laser intensity in different laser bands, including VIS (520 nm), NIR-I (1060 nm), and NIR-II (1550 and 2000 nm). The photocurrents increase linearly with intensity in all bands, and the dashed lines indicate the linear fitting. (C) Photocurrent density statistics for different types of materials under zero bias, including 1D [TeNWNs, WS 2 nanotubes (32)], 2D [CuInP 2 S 6 (33)], and 3D [BiFeO 3 (34), LiNbO 3 (35), KBNNO (36), halide (37), PLZTN (38), TTF-CA (39), BaTiO 3 (40), BBLT (41)] materials. As the dimension decreases, photocurrents show an elevated trend. TeNWNs exhibit the highest photocurrent densities available, benefiting from asymmetries due to both external interface effects and internal defects. (D) Summary of photosensitivity restored using different materials and mechanisms [Si-PV (14-16), NW-PV (42), capacitive (43), WC (1), rods-PT (4)]. Because of a narrow bandgap, high light absorption, and photoelectric conversion, TeNWNs push the photosensitivity from the VIS to a record NIR-II band (1550 nm, light red region), as illustrated by the red arrow. NW, nanowire; PT, photothermal; PV, photovoltaics; WC, wavelength conversion. (E) Schematic of TeNWN photocurrent testing under an electrophysiological platform, which integrates the multielectrode array, digital micromirror device (DMD), and 635 nm laser. A VIS laser (635 nm) was used to illuminate the DMD, which projected patterns onto the surface of TeNWNs. (F) Voltage response on the surface of the TeNWNs under a 635-nm laser visual pattern (circle and triangle) illumination. The color distribution is linearly mapped to the amplitude of voltage response on the surface of the TeNWNs. Laser intensity is 42.5 mW mm −2 , and the recording area is 1200 μm by 1200 μm. The corresponding projection pattern is shown at the top left.\ \ …

Ophthalmic assessments and fEEP recordings in TeNWN-implanted Macaca fascicularis. (A) Fundus photography (100°; top), NIR reflectance imaging (30°; middle), and B-scan OCT (bottom) of the implanted area in the right eye before and at 7, 28, 67, 90, and 112 days after the implant surgery. The green dashed lines indicate the cross-sectional position of the OCT B-scan, and the red arrowheads indicate the position of TeNWNs implant. (B) FFA at different time points (2, 5, 10, and 16 min) after intravenous injection of indocyanine green at 112 days after TeNWN implantation. In the image on the left, white arrowheads and white dots in the center indicate surgical sites from a separate study, and the green arrowhead marks the photocoagulation site used to seal retinal openings during the TeNWN implant surgery. In the images on the right, red arrowheads indicate the TeNWN implant. (C) Schematic of fEEP recording with NIR-I stimulation.(D) Scotopic (dark-adapted) fEEP responses of the TeNWN-implanted eye under NIR-I illumination (top; 500 ms, 940 nm, 60.48 μW mm −2 ) and VIS light illumination (bottom; 500 ms, 635 nm, 35.71 μW mm −2 ) at 19 days after TeNWN implantation. (E) Scotopic (dark-adapted) fEEP responses of a nonimplanted eye under NIR-I illumination (top; 500 ms, 940 nm, 60.48 μW mm −2 ) and a TeNWN-implanted eye under NIR-I illumination (middle; 500 ms, 940 nm, 60.48 μW mm −2 ) and VIS light illumination (bottom; 500 ms, 635 nm, 35.71 μW mm −2 ) at 90 days after TeNWN implantation. The green and magenta dots indicate the a-and b-wave components of fEEP. (F) Amplitude of the a-and b-waves of fEEP at 90 days after TeNWN implantation. Each dot indicates one recording session, and each session contains five trials. Data were analyzed by Student's t test. **P < 0.01; *P < 0.05. Data are presented as means ± SEM.

[Ophthalmic assessments and fEEP recordings in TeNWN-implanted Macaca fascicularis. (A) Fundus photography (100°; top), NIR reflectance imaging (30°; middle), and B-scan OCT (bottom) of the implanted area in the right eye before and at 7, 28, 67, 90, and 112 days after the implant surgery. The green dashed lines indicate the cross-sectional position of the OCT B-scan, and the red arrowheads indicate the position of TeNWNs implant. (B) FFA at different time points (2, 5, 10, and 16 min) after intravenous injection of indocyanine green at 112 days after TeNWN implantation. In the image on the left, white arrowheads and white dots in the center indicate surgical sites from a separate study, and the green arrowhead marks the photocoagulation site used to seal retinal openings during the TeNWN implant surgery. In the images on the right, red arrowheads indicate the TeNWN implant. (C) Schematic of fEEP recording with NIR-I stimulation.(D) Scotopic (dark-adapted) fEEP responses of the TeNWN-implanted eye under NIR-I illumination (top; 500 ms, 940 nm, 60.48 μW mm −2 ) and VIS light illumination (bottom; 500 ms, 635 nm, 35.71 μW mm −2 ) at 19 days after TeNWN implantation. (E) Scotopic (dark-adapted) fEEP responses of a nonimplanted eye under NIR-I illumination (top; 500 ms, 940 nm, 60.48 μW mm −2 ) and a TeNWN-implanted eye under NIR-I illumination (middle; 500 ms, 940 nm, 60.48 μW mm −2 ) and VIS light illumination (bottom; 500 ms, 635 nm, 35.71 μW mm −2 ) at 90

(Excerpt: abstract and figure captions from the ResearchGate record of the Science paper; the DMD platform appears in the Fig. 2 caption (multielectrode array + DMD + 635 nm laser projecting patterns onto the TeNWN film). Full text: Science 388, eadu2987 (DOI 10.1126/science.adu2987).)

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