Publisher's note to“Texture engineering of mono-crystalline silicon via alcohol-free alkali solution for efficient PERC solar cells”[J.Energy Chem.71(2022)104-107

The publisher regrets that the page range of this paper was incorrect due to production error,and we added al-a5 after page 107 to the pdf version to correct this mistake.

Texture engineering of mono-crystalline silicon via alcohol-free alkali solution for efficient PERC solar cells

Control of texture structures is an effective method to reduce surface reflectivity and enhance the efficiency of solar cells.In this paper,pyramid structures are prepared on mono-crystalline silicon wafers by cyclodextrin as surfactant to slow down the etching rate in alcohol-free alkali solution.Compared with volatile alcohol surfactant(e.g.isopropanol,IPA),the cyclodextrin not only possesses a relative high boiling point(1534.4℃),but displays non-toxic and biodegradable properties.Furthermore,the surface morphology,average reflectivity,surface recombination of mono-crystalline silicon wafers were studied in detail.The results show that cyclodextrin can decrease the size and depth of pyramid structures,and thus a lower average reflectivity of 7.5%was obtained.In addition,ray tracing simulation was performed to calculate the photo-generated carrier concentration of PN junction with different sizes of pyramids,and the conclusion is that the carrier concentration of small pyramids is much higher than that of large pyramids.Finally,the average efficiency of large-area mono-crystalline silicon PERC solar cells fabricated by cyclodextrin surfactant was 22.69%,which was 0.43%absolutely higher than that of conventional IPA surfactant.

Development of underwater electric manipulator based on interventional autonomous underwater vehicle (AUV)

In applications such as marine rescue,marine science,archaeology,and offshore industries,autonomous underwater vehicles(AUVs)are frequently used for survey missions and monitoring tasks,with most operations being performed by manned submersibles or remotely operated vehicles(ROVs)equipped with robotic arms,as they can be operated remotely for days without problems.However,they require expensive marine vessels and specialist pilots to operate them.Scientists exploring oceans are no longer satisfied with the use of manned submersibles and ROVs.There is a growing desire for seabed exploration to be performed using smarter,more flexible,and automated equipment.By improving the field operation and intervention capability of AUVs,large-scale and long-range seafloor exploration and sampling can be performed without the support of a mother ship,making it a more effective,economical,convenient,and rapid means of seafloor exploration and sampling operations,and playing a critical role in marine resource exploration.In this study,we explored the integration technology of underwater electric robotic arms and AUVs and designed a new set of electric manipulators suitable for water depths greater than 500 m.The reliability of the key components was analyzed by finite element analysis and,based on the theory of robot kinematics and dynamics,simulations were performed to verify the reliability of the key components.Experiments were conducted on land and underwater,trajectory tracking experiments were completed,and the experimental data in air and water were compared and analyzed.Finally,the objectives for further research on the autonomous control of the manipulator underwater were proposed.

Research on the sampling performance of a new bionic gravity sampler

Gravity sampling is of vital importance for sampling seabed sediments and understanding submarine sedimentary environments and resources.In this study,a new bionic sampler tube(BST)with non-smooth surface for low-disturbance and rapid sampling is presented.The BST with depressions and swellings on its surface was designed on the model of the non-smooth surface of the dung beetle.Sufficient theoretical calculations,numerical simulations,and experimental tests were carried out to study its sampling performance.The penetration depth,sample length,and frictional drag of the sampler tube were calculated.The finite element model and the coupled Eulerian-Lagrangian(CEL)method were used to analyze and compare its sampling performance.Laboratory and field gravity sampling tests were conducted and the results demonstrated the advantages of the BST in improving sampling performance and in reducing adhesion and drag.

Design and comparative analysis of self-propelling drill bit applied to deep-sea stratum drilling robot

Robotic subsea stratum drilling robot is a method for new subsea stratigraphic geological investigation and resource exploration.Resistance at the front end is the main source of resistance to the robot’s motion in the strata.Since there is no continuous and strong downward drilling force as in conventional drilling rigs,robot movement relies heavily on the drill bit to reduce the drilling resistance.In this study we propose a self-propelling drill bit that can discharge soil debris to provide propulsive force and reduce the resistance.The key parameter of the drill bit design,the spiral blade lead angle,was determined by theoretical analysis of the drill bit’s soil discharging effect.To verify the structural advantages of the self-propelling drill bit in reducing resistance,a comparative analysis with a conventional conical drill bit was conducted.The drilling process of both bits was simulated using finite element simulation at various rotation speeds,the penetration force and torque data of both drill bits were obtained,and tests prepared accordingly in subsea soil were conducted.The simulations and tests verified that the penetration force of the self-propelling drill bit was lower than that of the conventional conical drill bit.The self-propelling drill bit can reduce the resistance effectively,and may play an important role in the stratum movement of drilling robots.

A TiO_(2)nanotubes film with excellent antireflective and near-perfect self-cleaning performances

SiO_(2)/TiO_(2)composite films have been frequently used to realize the functions of self-cleaning and antireflection.Increasing the TiO_(2)volume ratio in SiO_(2)/TiO_(2)composite film is beneficial to enhance the self-cleaning effect,while high TiO_(2)content leads to a strong Rayleigh scattering and depresses the antireflective performance,resulting in a bottleneck problem for the dual-functional application.Here,we have achieved a high-quality TiO_(2)nanotubes film with excellent antireflective and near-perfect selfcleaning performances.Ultrasound assisted pickling method has been developed to effectively prepare the well-dispersed protonated titanate nanotubes colloid.After spin-coating and annealing treatment,glass substrate coated with double-side TiO_(2)nanotubes film has a peak transmittance of 99.2%and average transmittance of 97.4%at 400-800 nm.Ultra-high porosity of TiO_(2)nanotubes film(80%)and ultra-fine size of TiO_(2)nanotubes(8.6 nm in outer diameter)lead to excellent antireflective performance.With high UV absorptivity(80%at 254 nm)and formal quantum efficiency of stearic acid(10.9×10^(-3)),TiO_(2)nanotubes film shows near-perfect self-cleaning performance.A persistent anti-fogging ability is also presented.This study demonstrates the feasibility to fabricate pure TiO_(2)antireflective coating for glass substrate,extends application field of the classic TiO_(2)nanotubes,and sheds lights on the practical applications of high-powered TiO_(2)nanotube-based multi-functional films.